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Objectives Thelaziosis caused by the nematode Thelazia callipaeda (Spirurida, Thelaziidae) affects the eyes of domestic and wild carnivores, lagomorphs and even humans. The role of cats in spreading thelaziosis remains unclear. The present study assesses the current status of feline T callipaeda infection in Spain and presents the results of the first prophylactic trial conducted in this species. Methods We retrospectively analysed the occurrence of feline thelaziosis (study 1), examined its prevalence based on cross-sectional sampling of endemic areas (study 2), and assessed the therapeutic/prophylactic benefits of a spot-on (moxidectin) and therapeutic efficacy of an eye drop (ivermectin) formulation (study 3). Results In study 1, 69 Thelazia-infected cats were examined. Autochthonous cases were detected in 18/26 municipalities surveyed in Spain, which corresponds to 88.4% (n = 61/69) of the total number of cases. In study 2, 74 cats (20 from La Vera region and 54 from Orense province) were examined from 2011 to 2013. Ten of these cats (13.5%) were infected with T callipaeda. The infection prevalence was 40% (n = 8/20) in La Vera and 3.7% (n = 2/54) in Orense. The therapeutic efficacy of ivermectin was assessed over a summer (2011) in 12 cats, while that of moxidectin was examined over a 17-month period in seven cats. Four of these seven cats were subsequently included in an all-year-round prophylaxis trial. Treatment efficacy ranged from 91.7% (ivermectin) on day 28 after treatment to 100% (moxidectin) on day 14. Moxidectin prevented reinfections in cats. Conclusions and relevance Our data confirm the endemic status of T callipaeda infection in Spain, revealing its high prevalence in cats living in known endemic areas. Moxidectin was effective in treating and preventing infection. We strongly recommend the inclusion of thelaziosis in the differential diagnosis of pets and humans presenting with ocular manifestations, along with adequate preventive measures.

Thelazia callipaeda (Spirurida, Thelaziidae), known as oriental eyeworm, is a parasite infesting the eyes of many domestic and wild carnivores which can also cause human infections. Due to the fact that infections by T. callipaeda have been recently spreading through the Balkan Peninsula, the main aims of this mini review are to give a clear and concise overview of the clinical manifestations, diagnosis and treatment of thelasiosis in animals and humans as well as to update epidemiological data about thelaziosis in this area. Clinical manifestations of thelaziosis can vary from subclinical to severe. In both animals and humans, treatment of thelaziosis can be effectively achieved with the removal of the nematodes from the eye under local anesthesia using a cotton swab or fine forceps. In the treatment of animals, antiparasitic drugs should be used supplementarily to the mechanical removal of parasites, while in humans, the topical use of antibiotics is desirable in order to prevent secondary bacterial infection. The growing number of diagnosed thelasiosis cases in dogs in the Balkan Peninsula, and particularly among owned pets in urban areas of Serbia previously considered free of infection, indicates the spread of zoonotic T. callipaeda in the area and in close proximity to humans. Finally, cooperation between veterinarians and physicians is strongly advocated in favour of the development of effective preventive measures and strategies.

Rhabdochona fuscovaria n. sp. Alcantara, O��Dwyer & Silva (Figure 2���4) Description (based on one male and one female). Body narrow, elongate. Medium-sized nematodes with lightly transversely striated cuticle. Sexual dimorphism evident. Lateral alae present. Oval oral aperture surrounded by four lateral plates, four cephalic papillae and two amphids. Prostom funnel-shaped, relatively short with basal teeth, anterior margin of prostom armed internally with 14 teeth (7 dorsal and 7 ventral). Vestibule relatively long, straight. Deirids small, simple, stylet-shaped, anterior to mid-length of vestibule. Glandular oesophagus longer than muscular oesophagus. Tail tip of both sexes conical. Males without caudal alae; spicules unequal and dissimilar. Male. Body 11.10 mm long and 98.8 wide. Vestibule including prostom 141.1 long and 7.4 wide; prostom 25 long and 10.1 wide in lateral view. Muscular oesophagus 362.8 long, 26.2 wide; glandular oesophagus 1.82 mm long, 71.4 wide; length ratio of both parts of oesophagus 1:5. Entire oesophagus and vestibule representing 20.9% of body length. Nerve ring encircling muscular oesophagus, 206.4 from anterior end of body. Excretory pore and deirids 321.9 and 56.3 from anterior extremity, respectively. Nine pairs precloacal papillae, 8 subventral pairs and 1 lateral pair (between the 3 rd and 4 th subventral pairs). Nine postcloacal papillae pairs: 7 ventral pairs and 2 ventrolateral pairs (one between the 1 st and 2 nd pairs and 1 after the last ventral papillae pair). Longitudinal ventral cuticular ridges (area rugosa) absent. Longer (left) spicule 585.7 long; shaft 285.3 long, representing 48.7% of entire spicule length; distal tip slightly widened, moderately dilated; right spicule boat-shaped, 132.9 long, without dorsal barb at distal tip. Length ratio of spicules 1:4.4. Tail 452.5 long. Female. Body 16.65 mm long and 139.4 wide. Vestibule including prostom 143.3 long and 8.6 wide, prostom 31 long and 15.9 wide. Muscular oesophagus 358.5 long, 32.1 wide; glandular oesophagus 2.14 mm long, 69.2 wide; length ratio of both parts of oesophagus 1:5.9. Entire oesophagus and vestibule representing 15.8% of body length. Nerve ring, excretory pore and deirids 222.5, 333.1, and 77.4 from anterior extremity, respectively. Tail conical, 334.4 long. Vulva postequatorial, 9.26 mm from anterior extremity, at 55.6% of body length; vulval lips not elevated. Muscular vagina directed posteriorly from vulva. Eggs oval, numerous, with no filaments, thick-walled, embryonated, size 29.2���35.4 �� 15.7���22.8, with smooth surface. Taxonomic summary Type locality: S��o Sebasti��o do Para��so farm (21��50���41.83���S, 48��28���10.24���W), municipality of Boa Esperan��a do Sul, S��o Paulo State, Brazil. Type host: Scinax fuscovarius (A. Lutz, 1925). Site of infection: Stomach. Prevalence: one host infect of four frogs examined. Type material: Holotype (CHIOC 39104), adult male; and Allotype (CHIOC 39105), adult female (deposited in the Helminthological Collection of the Instituto Oswaldo Cruz - CHIOC, after acceptance of the manuscript) Zoobank number: http://zoobank.org/ urn:lsid:zoobank.org:act: 01B5EC2C-7AAD-44A2-B0F8-C87AA77AE83A. ......continued on the next page ......continued on the next page ......continued on the next page ......continued on the next page ......continued on the next page Etymology: The epithet refers to the name of the host, which is the first anuran described as a host of Rhabdocona in the Americas. Remarks. Moravec (2010) argued that the South American Rhabdochona spp. probably derived from the North American species since they have no similarity with African congeners. Despite this, we have compared the new species with all others from the Nearctic and Neotropical regions. Rhabdochona fuscovaria sp. n. differs from all congeneric species by the combination of a unique set of morphological characters including the following: 1) morphology of deirids, 2) presence of 14 anterior prostomal teeth, 3) caudal alae absent; 4) morphology of spicules, 5) eggs with no filaments, and 6) caudal papillae arrangement (9:0:9). The nematode genus Rhabdochona Railliet, 1916 comprises about 100 species (Moravec 2010). Rhabdochona fuscovaria sp. n. has 14 teeth in the prostom. In the Americas, 14 Rhabdochona spp. have the same characteristic (Table 1). Of these, 10 species occour in the Neartic region (R. canadensis Moravec & Arai, 1971, Rhabdochona canadensis bifilamentosa Moravec & Huffman, 1988, R. cascadilla Wigdor, 1918, R. catostomi Kayton, Kritsky & Tobias, 1979, R. cotti Gustafson, 1949, R. decaturensis Gustafson, 1949, R. ictalurid Aguilar-Aguilar, Rosas-Valdez & P��rez-Ponce de Le��n, 2010, Rhabdochona kidderi texensis Moravec & Huffman, 1988, R. milleri Choquette, 1951, and Rhabdochona zacconis Yamaguti, 1935) and four in the Neotropical region (R. acuminata Molin, 1860, R. kidderi kidderi Pearse, 1936, Rhabdochona osorioi Santacruz, Garc��a & P��rez-Ponce de Le��n, 2019, and Rhabdochona uruyeni (Diaz-Ungrfa, 1968). However, among the 14 species that present 14 teeth, only five species have simple deirids like Rhabdochona fuscovaria sp. n., as follow: R. acuminata, R. cotti, R. decaturensis, R. osorioi, and R. uruyeni. Rhabdochona acuminata is found in a wide array of distantly related hosts (Characiformes and Siluriformes) (Cremonte et al. 2002; Ramallo 2005; Pinto et al. 2010). This species is similar to the new species in both possessing 14 teeth in the prostom, single deirids, and postequatorial vulva. However, Rhabdochona fuscovaria sp. n. can be readily distinguished from R. acuminata by the number of postanal papillae in males (9 pairs vs 6���7 pairs). Rhabdochona cotti is a parasite of the instestine of Scorpaeniformes from USA and Canada (Moravec & Muzzall 2007). This species can be easily differentiated from the new species by the presence of eggs with filaments. In addition, Rhabdochona fuscovaria sp. n. differs from R. cotti by the number post caudal papillae (9 pairs vs. 6 pairs, respectively). Rhabdochona decaturensis, a parasite of Perciformes in the USA and Canada (Gustafson 1949, Moravec &Arai 1971) has a spicule exceeding a length of 1 mm, while the spicule Rhabdochona fuscovaria sp. n. is small (585.7 ��m long). Additionally, the new species differs from R. decaturensis species by the caudal papillae arrangement (9:0:9 vs. 7-9:0:6). Rhabdochona osorioi is a parasite of Characiformes freshwater fishes from Mexico (Santa Cruz et al. 2019). This species differs from Rhabdochona fuscovaria sp. n. in the left spicule, which is smaller than the new species (414���451 vs 585.7). The new species has 18 caudal papillae pairs while R. osorioi has 22 pairs. Rhabdochona uruyeni, a parasite found in South American Characiformes and Sciaenidae freshwater fishes (Pinto et al. 2010), differs in the number of caudal papillae, the tail size, and oesophagus size: Rhabdochona fuscovaria sp. n. has 9 preclocal papilla pairs and 9 postcloacal papilla pairs, tail 452.6 long, muscular esophagus 362.8 long: Rhabdochona uruyeni has 8-10 pairs precloacal papillae and 5 pairs + 1 postcloacal papillae, tail 180���230 long, and a muscular esophagus 120���150 long., Published as part of Alcantara, Edna Paulino De, ��ngari, Leticia Pereira, Ferreira-Silva, Cristiana, Emmerich, Enzo, Pinheiro, Raul Henrique Da Silva, O��Dwyer, Lucia Helena & Silva, Rein- Aldo Jos�� Da, 2021, Rhabdochona fuscovaria sp. n. (Nematoda: Rhabdochonidae) from the stomach of frog Scinax fuscovarius (Anura: Hylidae) in Brazil, pp. 569-584 in Zootaxa 5067 (4) on pages 571-581, DOI: 10.11646/zootaxa.5067.4.5, http://zenodo.org/record/5683457, {"references":["Moravec, F. & Arai, H. P. (1971) The North and Central American species of Rhabdochona Railliet 1916 (Nematoda: Rhabdochonidae) of fishes, including Rhabdochona canadensis sp. nov. Journal of the Fisheries Research Board of Canada, 28, 1645 - 1662. https: // doi. org / 10.1139 / f 71 - 245","Moravec F. & Huffman, D. G. (1988) Rhabdochona longleyi sp. n. (Nematoda: Rhabdochonidae) from blind catfishes, Trogloglanis pattersoni and Satan eurystomus (Ictaluridae) from the subterranean waters of Texas. Folia Parasitologica (Praha), 35 (3), 235 - 43.","Wigdor, M. (1918) Two new nematodes common in some fishes of Cayuga Lake. Journal of Parasitology, 5, 29 - 34. https: // doi. org / 10.2307 / 3271176","Kayton, R. J., Kritsky, D. C. & Tobias, R. C. (1979) Rhabdochona catostomi sp. n. (Nematoda: Rhabdochonidae) from the intestine of Catostomuss spp. (Catostomidae). Proceedings of the Helminthological Society of Washington, 46, 224 - 227.","Moravec, F. & Muzzall, P. (2007) Redescription of Rhabdochona cotti (Nematoda, Rhabdochonidae) from Cottus caeruleomentum (Teleostei, Cottidae) in Maryland, USA, with remarks on the taxonomy of North American Rhabdochona spp. Acta Parasitologica, 52, 51. https: // doi. org / 10.2478 / s 11686 - 006 - 0049 - x","Aguilar-Aguilar, R., Rosas-Valdez, R. & de Leon, G. P. P. (2010) Rhabdochona ictaluri sp. nov. (Nematoda, Rhabdochonidae) from ictalurid catfishes in Mexico. Acta Parasitologica, 55, 276 - 280. https: // doi. org / 10.2478 / s 11686 - 010 - 0035 - 1","Margolis, L., Moravec, F. & McDonald, T. E. (1975) Rhabdochona kisutchi sp. nov. (Nematoda: Spiruroidea) from coho salmon, Oncorhynchus kisutch (Walbaum), of western Canada. Canadian Journal of Zoology, 53, 960 - 966. https: // doi. org / 10.1139 / z 75 - 111","Caspeta-Mandujano, J. M., Moravec, F. & Salgado-Maldonado, G. (2001) Two new species of rhabdochonids (Nematoda: Rhabdochonidae) from freshwater fishes in Mexico, with a description of a new genus. Journal of Parasitology, 87, 139 - 143. https: // doi. org / 10.1645 / 0022 - 3395 (2001) 087 [0139: TNSORN] 2.0. CO; 2","Moravec, F., Margolis, L. & Boyce, N. P. (1981) Some nematodes of the genus Rhabdochona (Spirurida) from fishes of Japan. Acta Societatis Zoologicae Bohemoslovacae, 45, 277 - 290.","Cremonte, F., Navone, G. T., Gosztonyi, A. E. & Kuba, L. (2002) Redescription of Rhabdochona (Rhabdochona) acuminata (Nematoda: Rhabdochonidae) from freshwater fishes from Patagonia (Argentina), the geographical implications. Journal of Parasitology, 88, 934 - 941. https: // doi. org / 10.1645 / 0022 - 3395 (2002) 088 [0934: RORRAN] 2.0. CO; 2","Mejia-Madrid, H. & Perez-Ponce de Leon, G. (2003) Rhabdochona ahuehuellensis n. sp. (Nematoda: Rhabdochonidae) from the Balsas Goodeid, Ilyodon Whitei (Osteichthyes: Gooedeidae), in Mexico. Journal of Parasitology, 89 (2), 356 - 361. https: // doi. org / 10.1645 / 0022 - 3395 (2003) 089 [0356: RANSNR] 2.0. CO; 2","Moravec, F. & Coy-Otero, A. (1987) Rhabdochona cubensis sp. nov. (Nematoda: Rhabdochonidae) from the freshwater fish Gambusia punctata from Cuba. Helminthologia, 24, 103 - 110.","Ramallo, G. (2005) Observations on two Rhabdochona species (Nematoda: Rhabdochonidae) from freshwater fishes in Argentina, including description of Rhabdochona fabianae n. sp. Journal of Parasitology, 91 (2), 415 - 419. https: // doi. org / 10.1645 / GE- 3413","Caspeta-Mandujano, J. M., Aguilar-Aguilar, R. & Salgado-Maldonado, G. (2002) Rhabdochona guerreroensis n. sp. (Nematoda: Rhabdochonidae) from the intestine of the Gobiid Sicydium multipunctatum from fresh waters in Mexico. Journal of Parasitology, 88 (4), 746 - 749. https: // doi. org / 10.1645 / 0022 - 3395 (2002) 088 [0746: RGNSNR] 2.0. CO; 2","Sanchez-Alvarez, A., Garcia-Prieto, L. & Perez-Ponce de Leon, G. (1998) A new species of Rhabdochona Railliet, 1916 (Nematoda: Rhabdochonidae) from endemic goodeids (Cyprinodontiformes) from two Mexican lakes. Journal of Parasitology, 84, 840 - 845. https: // doi. org / 10.2307 / 3284600","Santacruz, A., Ornelas-Garcia, C. P. & Perez-Ponce De Leon, G. (2019) Diversity of Rhabdochona mexicana (Nematoda: Rhabdochonidae), a parasite of Astyanax spp. (Characidae) in Mexico and Guatemala, using mitochondrial and nuclear genes, with the description of a new species. Journal of Helminthology, 94 (e 34), 1 - 11. https: // doi. org / 10.1017 / S 0022149 X 19000014","Pinto, M. R., Noronha, D., Knoff, M. & Gomes, D. C. (2010) Rhabdochona (R.) uruyeni (Nematoda, Rhabdochonidae) in Brazil: present status of South American Rhabdochona Railliet with a worldwide bibliographical survey of the genus from 1845 to 2010. Neotropical Helminthology, 4, 49 - 69."]}

Rhabdochona fuscovaria n. sp. Alcantara, O´Dwyer & Silva (Figure 2–4) Description (based on one male and one female). Body narrow, elongate. Medium-sized nematodes with lightly transversely striated cuticle. Sexual dimorphism evident. Lateral alae present. Oval oral aperture surrounded by four lateral plates, four cephalic papillae and two amphids. Prostom funnel-shaped, relatively short with basal teeth, anterior margin of prostom armed internally with 14 teeth (7 dorsal and 7 ventral). Vestibule relatively long, straight. Deirids small, simple, stylet-shaped, anterior to mid-length of vestibule. Glandular oesophagus longer than muscular oesophagus. Tail tip of both sexes conical. Males without caudal alae; spicules unequal and dissimilar. Male. Body 11.10 mm long and 98.8 wide. Vestibule including prostom 141.1 long and 7.4 wide; prostom 25 long and 10.1 wide in lateral view. Muscular oesophagus 362.8 long, 26.2 wide; glandular oesophagus 1.82 mm long, 71.4 wide; length ratio of both parts of oesophagus 1:5. Entire oesophagus and vestibule representing 20.9% of body length. Nerve ring encircling muscular oesophagus, 206.4 from anterior end of body. Excretory pore and deirids 321.9 and 56.3 from anterior extremity, respectively. Nine pairs precloacal papillae, 8 subventral pairs and 1 lateral pair (between the 3 rd and 4 th subventral pairs). Nine postcloacal papillae pairs: 7 ventral pairs and 2 ventrolateral pairs (one between the 1 st and 2 nd pairs and 1 after the last ventral papillae pair). Longitudinal ventral cuticular ridges (area rugosa) absent. Longer (left) spicule 585.7 long; shaft 285.3 long, representing 48.7% of entire spicule length; distal tip slightly widened, moderately dilated; right spicule boat-shaped, 132.9 long, without dorsal barb at distal tip. Length ratio of spicules 1:4.4. Tail 452.5 long. Female. Body 16.65 mm long and 139.4 wide. Vestibule including prostom 143.3 long and 8.6 wide, prostom 31 long and 15.9 wide. Muscular oesophagus 358.5 long, 32.1 wide; glandular oesophagus 2.14 mm long, 69.2 wide; length ratio of both parts of oesophagus 1:5.9. Entire oesophagus and vestibule representing 15.8% of body length. Nerve ring, excretory pore and deirids 222.5, 333.1, and 77.4 from anterior extremity, respectively. Tail conical, 334.4 long. Vulva postequatorial, 9.26 mm from anterior extremity, at 55.6% of body length; vulval lips not elevated. Muscular vagina directed posteriorly from vulva. Eggs oval, numerous, with no filaments, thick-walled, embryonated, size 29.2–35.4 × 15.7–22.8, with smooth surface. Taxonomic summary Type locality: São Sebastião do Paraíso farm (21°50’41.83”S, 48°28’10.24”W), municipality of Boa Esperança do Sul, São Paulo State, Brazil. Type host: Scinax fuscovarius (A. Lutz, 1925). Site of infection: Stomach. Prevalence: one host infect of four frogs examined. Type material: Holotype (CHIOC 39104), adult male; and Allotype (CHIOC 39105), adult female (deposited in the Helminthological Collection of the Instituto Oswaldo Cruz - CHIOC, after acceptance of the manuscript) Zoobank number: http://zoobank.org/ urn:lsid:zoobank.org:act: 01B5EC2C-7AAD-44A2-B0F8-C87AA77AE83A. ......continued on the next page ......continued on the next page ......continued on the next page ......continued on the next page ......continued on the next page Etymology: The epithet refers to the name of the host, which is the first anuran described as a host of Rhabdocona in the Americas. Remarks. Moravec (2010) argued that the South American Rhabdochona spp. probably derived from the North American species since they have no similarity with African congeners. Despite this, we have compared the new species with all others from the Nearctic and Neotropical regions. Rhabdochona fuscovaria sp. n. differs from all congeneric species by the combination of a unique set of morphological characters including the following: 1) morphology of deirids, 2) presence of 14 anterior prostomal teeth, 3) caudal alae absent; 4) morphology of spicules, 5) eggs with no filaments, and 6) caudal papillae arrangement (9:0:9). The nematode genus Rhabdochona Railliet, 1916 comprises about 100 species (Moravec 2010). Rhabdochona fuscovaria sp. n. has 14 teeth in the prostom. In the Americas, 14 Rhabdochona spp. have the same characteristic (Table 1). Of these, 10 species occour in the Neartic region (R. canadensis Moravec & Arai, 1971, Rhabdochona canadensis bifilamentosa Moravec & Huffman, 1988, R. cascadilla Wigdor, 1918, R. catostomi Kayton, Kritsky & Tobias, 1979, R. cotti Gustafson, 1949, R. decaturensis Gustafson, 1949, R. ictalurid Aguilar-Aguilar, Rosas-Valdez & Pérez-Ponce de León, 2010, Rhabdochona kidderi texensis Moravec & Huffman, 1988, R. milleri Choquette, 1951, and Rhabdochona zacconis Yamaguti, 1935) and four in the Neotropical region (R. acuminata Molin, 1860, R. kidderi kidderi Pearse, 1936, Rhabdochona osorioi Santacruz, García & Pérez-Ponce de León, 2019, and Rhabdochona uruyeni (Diaz-Ungrfa, 1968). However, among the 14 species that present 14 teeth, only five species have simple deirids like Rhabdochona fuscovaria sp. n., as follow: R. acuminata, R. cotti, R. decaturensis, R. osorioi, and R. uruyeni. Rhabdochona acuminata is found in a wide array of distantly related hosts (Characiformes and Siluriformes) (Cremonte et al. 2002; Ramallo 2005; Pinto et al. 2010). This species is similar to the new species in both possessing 14 teeth in the prostom, single deirids, and postequatorial vulva. However, Rhabdochona fuscovaria sp. n. can be readily distinguished from R. acuminata by the number of postanal papillae in males (9 pairs vs 6–7 pairs). Rhabdochona cotti is a parasite of the instestine of Scorpaeniformes from USA and Canada (Moravec & Muzzall 2007). This species can be easily differentiated from the new species by the presence of eggs with filaments. In addition, Rhabdochona fuscovaria sp. n. differs from R. cotti by the number post caudal papillae (9 pairs vs. 6 pairs, respectively). Rhabdochona decaturensis, a parasite of Perciformes in the USA and Canada (Gustafson 1949, Moravec &Arai 1971) has a spicule exceeding a length of 1 mm, while the spicule Rhabdochona fuscovaria sp. n. is small (585.7 µm long). Additionally, the new species differs from R. decaturensis species by the caudal papillae arrangement (9:0:9 vs. 7-9:0:6). Rhabdochona osorioi is a parasite of Characiformes freshwater fishes from Mexico (Santa Cruz et al. 2019). This species differs from Rhabdochona fuscovaria sp. n. in the left spicule, which is smaller than the new species (414–451 vs 585.7). The new species has 18 caudal papillae pairs while R. osorioi has 22 pairs. Rhabdochona uruyeni, a parasite found in South American Characiformes and Sciaenidae freshwater fishes (Pinto et al. 2010), differs in the number of caudal papillae, the tail size, and oesophagus size: Rhabdochona fuscovaria sp. n. has 9 preclocal papilla pairs and 9 postcloacal papilla pairs, tail 452.6 long, muscular esophagus 362.8 long: Rhabdochona uruyeni has 8-10 pairs precloacal papillae and 5 pairs + 1 postcloacal papillae, tail 180–230 long, and a muscular esophagus 120–150 long.

Made available in DSpace on 2022-04-29T08:46:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-11-12 A new nematode species, Rhabdochona (Rhabdochona) fuscovaria sp. n. (Rhabdochonidae), is described based on specimens collected from the stomach of the snouted treefrog Scinax fuscovarius (Hylidae) in the So Sebastio do Paraso farm, municipality of Boa Esperan do Sul, southeastern Brazil. This species is characterized by deirids small, simple and stylet shaped, prostom funnel-shaped with 14 teeth, conspicuous left spicule (585.7 m), distal tip slightly widened, moderately dilated, right spicule (132.9 m), boat-shaped, without dorsal barb at the distal tip, 18 pairs of caudal papillae (9 pairs precloacal and 9 pairs postcloacal), and nonfilamented eggs. This is the fourth species described for South America and the 13th for the Neotropical Region. Division of Parasitology So Paulo State University Research and Teaching Laboratory of Wild Animals So Paulo, Campus Botucatu Brazil Laboratrio de Histologia e Embriologia Animal, Instituto da Sade e Produo Animal, Universidade Federal Rural da Amaznia, Belm, Par, Brasil. . user@example.com

Thelazia longicaudata Schuurmans Stekhoven, 1951 Host: Strix rufipes rufipes. SI: eyes. Lo: Pozo Hondo, Santiago del Estero Province. Material deposited: CH–N–FML 1297. Reference: Schuurmans Stekhoven (1951)., Published as part of Drago, Fabiana B., Núñez, Verónica & Díaz, Mariano Dueñas, 2020, Checklist of the nematode parasites of wild birds of Argentina, pp. 43-61 in Revue suisse de Zoologie 127 (1) on page 53, DOI: 10.35929/RSZ.0005, http://zenodo.org/record/5743511, {"references":["Schuurmans Stekhoven J. H. 1951. Nematodes parasitos de anfibios, pajaros y mamiferos de la Republica Argentina. Acta Zoologica Lilloana 3: 315 - 400."]}

A commented checklist of the nematodes parasites of Argentinean wild birds is presented. This is the first compilation of parasitological papers about nematodes of Argentinean birds published between 1873 and November 2019. This review includes information about 64 nematode nominal species and 13 taxa identified at generic level, belonging to five orders, 16 superfamilies, 20 families, and 44 genera. Five species were considered incertae sedis, because they were described based only on larval stages, and one species was maintained as species inquirenda. The highest number of taxa of nematodes was recorded in the family Acuariidae with 20 nominal species and two taxa identified at generic level, followed by Anisakidae with eight nominal species and one taxon identified at generic level, and Tetrameridae with eight nominal species and two taxa identified at generic level. Of the 1042 species of birds reported in Argentina, only 65 (6.24%) were reported as hosts of adult nematodes. The families of birds with the highest number of reported taxa were Tinamidae (12 nematode taxa), Laridae (11), Anatidae (8) and Phalacrocoracidae (7). The present review provides data on hosts, geographical distribution, sites of infection, location of material deposited in Helminthological Collections, references, and taxonomic comments. A host/parasite list is also provided., Facultad de Ciencias Naturales y Museo

The eye nematode Thelazia callipaeda Railliet et Henry, 1910 (Spirurida: Thelaziidae) is a vector-borne zoonotic nematode infecting a range of wild and domestic carnivores as well as humans. It is considered to be a causative agent of emerging and neglected disease and currently invades central part of Europe. Nematodes were collected from the eye of a dog living in Prague, which never travelled outside the Czech Republic. The nematodes were identified based on their morphology and partial sequence of the cox1 gene as T. callipaeda haplotype 1. This finding represents the northernmost record of autochthonous canine thelaziosis in Europe. The insufficient control of imported animals as well as free movement of dogs and wild carnivores within Europe probably facilitates spreading of T. callipaeda throughout the continent. To better understand the spreading of T. callipaeda and to prevent its zoonotic transmissions, information about the risk of this infection in newly invaded countries should be disseminated not only among veterinarians and physicians, but also within the community of pet owners and hunters.

Thelazia callipaeda has been regarded in Europe in the last few decades as a "new" agent of an ocular disease in dogs, cats, several wild species, and not least in humans. After the first European description in Italy, in 1989, the parasite has been reported in many other countries, showing a widespread distribution of this parasite. The first case of canine thelaziosis in Romania has been reported in 2015, and it has been followed by other studies confirming the presence of the nematode in dogs or broadening the host spectrum with some wild carnivore species that have been found positive. Despite being considered suitable primary hosts for T. callipaeda, infection with T. callipaeda in domestic cat is rarely reported in Europe, probably due to some behavioral and physical particularities of this host. This study describes the first autochthonous report of T. callipaeda infection in a domestic cat from Romania. Additionally, to these findings, new geographical records of canine thelaziosis are being revealed, confirming the increased risk of this emerging vector-borne zoonosis.

Thelazia callipaeda (Spirurida, Thelaziidae) is a vector-borne zoonotic nematode parasite of the conjunctival sac of a large spectrum of hosts, currently having an expanding distribution range throughout Europe. In Romania, the parasite has a relatively large distribution range and host spectrum. However, the presence of T. callipaeda in red foxes ( Vulpes vulpes) has not yet been confirmed. The aim of the present study was to assess the prevalence and geographical distribution of T. callipaeda in red foxes from Romania. A total of 514 animals originating from 10 counties of western Romania were evaluated for the presence of T. callipaeda. Overall, 151 red foxes (29.38%) were positive. No significant differences were noticed between sex and age groups of positive foxes. In total, 3,350 adult nematodes were recovered. The intensity of infection had a mean value of 23.2, while the sex ratio was 2.2:1 in favor of females. In 91 foxes, both eyes were affected, while 60 harbored unilateral infection. Sequence analysis of the cox 1 gene of one nematode from each positive fox ( n=151) revealed the exclusive presence of haplotype h1. We report a relatively high prevalence and distribution range of T. callipaeda infection in red foxes in Romania, highlighting their potential role as a wildlife reservoir.

Thelazia callipaeda (Spirurida, Thelaziidae), the so-called oriental eyeworm, has been increasingly reported as an agent of infection in animals and humans from many European countries. Clinical signs range from subclinical to moderate or severe ocular disorders (e.g., epiphora, photophobia, conjunctivitis, keratitis, ulcers). The disease has been also diagnosed in animals from countries of the Balkan area (e.g., Croatia, Bosnia and Herzegovina and Serbia), but only a single case of canine thelaziosis, presumably autochthonous, was reported in Northern Greece. In this study, we provide robust information of the occurrence of thelaziosis in Greece by reporting autochthonous cases of thelaziosis in dogs (n = 46), cats (n = 3) and in one rabbit (Oryctolagus cuniculus) living in Northern and Central regions of Greece. The occurrence of a single haplotype of the cytochrome oxidase subunit 1 gene confirms that the same zoonotic haplotype of the parasite circulating in Europe is also spreading in Greece. The increased awareness of this parasitosis is crucial to limit the risk of further infections in both humans and animals in European countries.

Thelazia callipaeda (Spirurida, Thelaziidae) causes ocular infection in carnivorous animals and humans. While growing numbers of companion dogs and sometimes cats are being diagnosed with thelaziosis, little is known about its real spread. As it has been also diagnosed in wild animals and human beings, it is considered a potential emerging zoonotic disease. This study provides information about the spread of the parasite in dogs in Spain since its initial description in 2010 until 2018. The first detection of T. callipaeda in the Principality of Andorra in 2017 is also reported. Two different studies were conducted: a) a survey in which clinical cases from veterinary practices were collected and b) a prevalence study in two endemic areas in western and central Spain (Site 1 La Vera region, Cáceres, and Site 2 El Escorial municipality, Madrid). In total, 1114 cases of thelaziosis were detected in 121 municipalities of Spain and 6 municipalities of Andorra. In 92 out these 127 municipalities, reports were of autochthonous cases. Six hundred twenty-three out of 1114 presented data collection sheet and were included in the statistical analysis: 510 cases identified by veterinarians in Spain and Andorra in Study 1, and 113 cases detected among the 234 dogs (48.3 %) examined in the prevalence study (Study 2). Prevalences were 61.3 % (84/137) for Cáceres and 29.9 % (29/97) for Madrid, being Site 1 significantly more risky (P 0.0001, odds ratio: 3.72, CI: 2.14-4.47 %) compared to Site 2. Our study updates data for canine thelaziosis reported in the last decade in Spain and Andorra. Results highlight the urgent need for prevention strategies to control the spread of this potential zoonotic disease.

Over the last 30 years, Thelazia callipaeda (Spirurida: Thelaziidae) has increasingly been reported as an agent of ocular infections in animals and humans throughout Europe. Following the cases of canine ocular thelaziosis recently recorded in Austria for the first time, in the present paper, we describe the first case of T. callipaeda infection in an Austrian cat with no history of traveling abroad. This finding further supports the occurrence of the parasite’s autochthonous transmission cycle in the country. The cat showed serous ocular discharge, conjunctival hyperemia, and mild conjunctival edema in the right eye. Mechanical removal of the parasite from the cat’s eye, in combination with milbemycin oxime/praziquantel oral treatment and topical use of tobramycin/dexamethasone eye drops led to complete resolution of the clinical signs within 2 weeks. Results presented in the current study are of great importance for the local veterinarians who seemed largely unaware of this zoonotic parasite. Therefore, increased awareness of medical and veterinary communities is imperative for preventing further infections in both animals and humans.

Infekcije oka mogu da izazovu metazoe-helminti. Dugo se za ove parazitoze verovalo da su rasprostranjene samo u tropskim krajevima sveta. U poslednje vreme najčešće su opisane subkonjuktivalne infekcije adultima ili nezrelim formama vrste D. repens, koje su filarije kanida i za koje je čovek samo slučajni nosilac. S obzirom na činjenicu da se na teritoriji grada Niša dijagnostikuje telazioza (thelasiosis) kod pasa, opis morfoloških karakteristika roda, životnog ciklusa, rasprostranjenosti i kliničkog značaja ovog uzročnika zoonoza prvenstveno je bio cilj ovog rada. Rod Thelazia (Spirurida, Thelaziidae) obuhvata kosmopolitsku grupu očnih crva spirurids, odgovornih za očne infekcije domaćih i divljih životinja i ljudi koje se prenose različitim vrstama mušica. Morfološki odrasli crvi su kremasto bele boje, končastog izgleda, dužine do 2 cm. Dokazano je da su muve reda Diptera, porodice Drosophilidae, roda Phortica, vektori i prelazni domaćini vrste T. callipaeda. Nematode lokalizovane u konjunktivalnom prostoru, suznim putevima i okolnim okularnim tkivima kanida, felida, glodara i ljudi, mogu izazvati blage simptome (pojačano suzenje, svrab, osećaj stranog tela, bol, otok, zamagljen vid, eksudativni konjunktivitis) do onih jako ozbiljnih i teških (zamućenje i ožiljavanje konjunktive i rožnjače, ulceracije rožnjače i keratitis) ukoliko se ne leče. Kako bi se obezbedila sigurna dijagnoza telazioze i sprovođenje odgovarajućeg tretmana primarnih problema i komplikacija, neophodno je kontinuirano medicinsko obaveštavanje i svest o ovoj infekciji.

El presente trabajo reporta el hallazgo de una filariosis ocular en una gallina doméstica adulta, criada en traspatio en una comunidad cercana al río La silla, al sur de Nuevo León, México. La gallina fue remitida para una práctica de veterinaria debido a que presentaba debilidad y diarrea. A la necropsia, fueron encontrados tres nematodos debajo de la membrana nictitante en ambos ojos. Los nematodos fueron identificados como Oxyspirura mansoni. El diagnóstico fue confirmado cuando el huésped intermediario de O. mansoni, la cucaracha de Surinam (Pycnoscelus surinamensis), fue hallado en el lugar donde habitaba la gallina.

Rhabdochona milleri Choquette, 1951 Description (after Choquette 1951a, and Moravec & Arai 1971). With characteristics of the genus. Male (1 specimen): 6.94 long, 0.176 maximum width. Prostom funnel-shaped, 0.018 long, with distinct basal teeth, lined internally with longitudinal ribs forming teeth directed forwardly (exact number not determined). Vestibule including prostom 0.144, muscular oesophagus 0.300, and glandular oesophagus 1.36 long. Small, bifurcate deirids 0.063, nerve ring 0.168, and excretory pore 0.237 from anterior end. Eight pairs of subventral and one pair of [presumably lateral] pre-cloacal papillae, and six pairs of post-cloacal papillae—five pairs subventral, one pair lateral (Fig. 48 A). Left spicule 0.402 long, with relatively blunt distal tip, and “slightly outlined” bifurcation (Fig. 48 B). Right spicule 0.129 long, with dorsal barb at distal end (Fig. 48 A). Length ratio of right to left spicule 1:3.12. Tail conical, 0.300 long, with sharp cuticular spike at tip. Females (3 specimens): 10.91–12.10 long, 0.136–0.163 maximum width. Prostom funnel-shaped, 0.021–0.024 long, with distinct basal teeth, and 14 teeth projecting forwardly (Fig. 48 C,D). Vestibule including prostom 0.111– 0.138, muscular oesophagus 0.270–0.297, and glandular oesophagus 1.59–2.35 long. Medium sized bifurcate deirids 0.063–0.081, nerve ring 0.186–0.189, and excretory pore 0.261 from anterior end. Vulva slightly postequatorial, 5.03–6.12 from posterior end. Eggs oval, 0.030–0.036 x 0.018–0.021. Surface of advanced eggs (containing larvae) smooth; poles provided with numerous fine filaments (Fig. 48 E), those on one pole arranged mostly in parallel giving the appearance of a short ribbon-like filament with the end frayed (Fig. 48 E, lower egg). Tail conical, 0.210–0.243 long, with sharp cuticular point. Comment: Moravec & Arai (1971) stated that “in many important features R. milleri resembles R. ovifilamenta, and subsequent detailed studies might prove their conspecificity”. Site: intestine Hosts: Carpiodes cyprinus (7); Moxostoma erythrurum (2); Moxostoma macrolepidotum (1, 2, 6); Oncorhynchus clarkii (3); Oncorhynchus mykiss (3); Prosopium coulterii (3); Prosopium williamsoni (4, 5); Rhinichthys cataractae (4, 5); Salvelinus fontinalis (3); Salvelinus malma (3) Distribution: Alberta, British Columbia, Ontario, Quebec Records: 1. Choquette 1951a (QC); 2. Dechtiar 1972b (ON); 3. Mudry & Anderson 1977 (AB); 4. Anon. 1978 (BC); 5. Arai & Mudry 1983 (BC); 6. Dechtiar & Christie 1988 (ON); 7. Dechtiar & Nepszy 1988 (ON), Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on page 76, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530, {"references":["Choquette, L. P. E. (1951 a) On the nematode genus Rhabdochona Railliet, 1916 (Nematoda: Spiruroidea). Canadian Journal of Zoology, 29, 1 - 16. http: // dx. doi. org / 10.1139 / z 51 - 001","Moravec, F. & Arai, H. P. (1971) The North and Central American species of Rhabdochona (Nematoda: Rhabdochonidae) of fishes, including Rhabdochona canadensis sp. nov. Journal of the Fisheries Research Board of Canada, 28, 1645 - 1662. http: // dx. doi. org / 10.1139 / f 71 - 245","Dechtiar, A. O. (1972 b) New parasite records for Lake Erie fish. Great Lakes Fishery Commission, Technical Report, No. 17, 20 pp.","Mudry, D. R. & Anderson, R. S. (1977) Helminth and arthropod parasites of freshwater fishes in Alberta, 1932 - 1975. Journal of Fish Biology, 11, 21 - 33. http: // dx. doi. org / 10.1111 / j. 1095 - 8649.1977. tb 04095. x","Arai, H. P. & Mudry, D. R. (1983) Protozoan and metazoan parasites of fishes from the headwaters of the Parsnip and McGregor Rivers, British Columbia: a study of possible parasite transfaunations. Canadian Journal of Fisheries and Aquatic Sciences, 40, 1676 - 1684. http: // dx. doi. org / 10.1139 / f 83 - 194","Dechtiar, A. O. & Christie, W. J. (1988) Survey of the parasite fauna of Lake Ontario fishes, 1961 to 1971. In: Nepszy, S. J. (Ed.), Parasites of Fishes in the Canadian waters of the Great Lakes. Great Lakes Fishery Commission, Technical Report, No. 51, 66 - 95.","Dechtiar, A. O. & Nepszy, S. J. (1988) Survey of the parasite fauna of selected fish species from Lake Erie, 1970 ̶ 1975. In: Nepszy, S. J. (Ed.), Parasites of Fishes in the Canadian waters of the Great Lakes. Great Lakes Fishery Commission, Technical Report, No. 51, 49 - 65."]}

Rhabdochona kisutchi Margolis, Moravec & McDonald, 1975 Description (after Margolis et al. 1975). With characteristics of the genus. Medium-sized worms with rudimentary pseudolabia. Mouth opening roughly hexagonal. Two fairly large lateral amphids and eight small submedian cephalic papillae arranged in an inner and outer circle of four each; papillae of inner circle at mouth margin. Prostom funnel-shaped with distinct basal teeth, and its anterior margin with 10 conical teeth (Fig. 47 A,B). Vestibule relatively long, straight (but S-shaped in specimens that the authors claim to be “older’). Deirids medium-sized, bifurcate, located near mid-point of vestibule (Fig. 47 B). Tail of both sexes “ending in blunt point”. Males (11 specimens, allotype in parentheses): 6.61–8.41 (6.90) long, 0.110–0.150 (0.150) maximum width. Prostom 0.024–0.027 (0.024), vestibule including prostom 0.108–0.153 (0.123), muscular oesophagus 0.225– 0.270 (0.233) and glandular oesophagus 1.35–2.29 (1.69) long. Deirids 0.060–0.075 (0.066), nerve ring 0.168– 0.240 (0.195) and excretory pore 0.249–0.351 (0.286) from anterior end. Subventral pre-cloacal papillae variable in number: allotype has nine on each side, paratypes with the combinations 7+8, 8+8, 8+9, 7+9, 8+10, and 10+10. Additional pair of lateral pre-cloacal papillae at level of 3rd subventral pair or slightly posterior to it. One paratype had two pairs of lateral papillae. Six pairs of post-cloacal papillae—five subventral and one lateral (Fig. 47 C). Left spicule 0.564–0.660 (0.627) long, with shaft representing about its distal half; proximal end slightly widened, distal tip lanceolate, with wide cuticular membrane; ventral process seen on distal tip when spicule protruding from cloacal opening (Fig. 47 D). Right spicule variable in shape, 0.087–0.135 (0.120) long; dorsal barb feebly developed, usually indistinct, its apparent presence depending perhaps on angle from which it is viewed. Length ratio of right to left spicule 1:4.80 to 1:6.48 (1:5.22). Tail 0.300–0.390 (0.360) long, “ending in blunt point”. Females (nine specimens, holotype in parentheses): gravid worms 12.04–17.38 (13.59) long, 0.190–0.272 (0.231) maximum width. Prostom funnel–shaped 0.030–0.036 (0.033), vestibule including prostom 0.126–0.198 (0.192), muscular oesophagus 0.285–0.361 (0.330), and glandular oesophagus 2.34–3.36 (2.87) long. Deirids 0.060–0.096 (0.090), nerve ring 0.174–0.276 (0.261) and excretory pore 0.411–0.420 (0.411) from anterior end. Tail 0.351– 0.450 (0.351) long, ending in “a blunt point”. Vulva slightly post-equatorial located 6.16–8.02 (6.25) from posterior end. Amphidelphic. Mature eggs oval, embryonated, always with gelatinous “formations” most often in shape of caps or lobes covering egg poles and partly their lateral surfaces; rarely polar “formations” tendril-shaped and as long as 0.045; in some eggs a long filiform filament, about 0.45 long, arises from proximo-lateral corner of one polar cap (Fig. 47 E,F,G). Eggs, excluding polar “formations”, “0.039–0.042 x 0.024 (0.039–0.042 x 0.024) [sic]”, polar caps usually 0.006–0.009 high. Sites: intestine, pyloric caeca Hosts: Oncorhynchus kisutch (1); Oncorhynchus mykiss (2, 3); Oncorhynchus nerka (2, 3); Prosopium williamsoni (2, 3); Salvelinus malma (2, 3, 4) Distribution: British Columbia Records: 1. Margolis et al. 1975; 2. Anon. 1978; 3. Arai & Mudry 1983; 4. Anon. 1984, Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on pages 73-76, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530, {"references":["Margolis, L., Moravec, F. & McDonald, T. E. (1975) Rhabdochona kisutchi sp. nov. (Nematoda: Spiruroidea) from coho salmon, Oncorhynchus kisutch (Walbaum), of western Canada. Canadian Journal of Zoology, 53, 960 - 966. http: // dx. doi. org / 10.1139 / z 75 - 111","Arai, H. P. & Mudry, D. R. (1983) Protozoan and metazoan parasites of fishes from the headwaters of the Parsnip and McGregor Rivers, British Columbia: a study of possible parasite transfaunations. Canadian Journal of Fisheries and Aquatic Sciences, 40, 1676 - 1684. http: // dx. doi. org / 10.1139 / f 83 - 194","Anthony, D. D. (1984) Helminth parasites of white bass (Morone chrysops) from Lake Nipissing, Ontario. Program and Abstracts. 59 th Annual Meeting, American Society of Parasitologists, 05 - 09 August 1984. Snowbird, Utah, p. 27."]}

Rhabdochona rotundicaudatum Byrne, 1992 Description (after Byrne 1992a). With characteristics of the genus. General characteristics: see those for R. cascadilla above. Male paratypes (means with ranges in parentheses): body 5.8 (5.0–6.7), prostom 0.018 (0.017–0.023), vestibule 0.090 (0.081–0.100), muscular oesophagus 0.224 (0.188–0.251) and glandular oesophagus 1.6 (1.2–1.9) long. Small bifurcate deirids 0.051 (0.033–0.057), nerve ring 0.133 (0.127–0.137) and excretory pore 0.200 (0.195–0.208) from anterior end. Caudal papillae digitiform: 18 to 21 pre-cloacal and 11 to 13 post-cloacal, mostly subventral. Phasmids minute, located just distal to most posterior pair of caudal papillae. Left spicule 0.388 (0.342– 0.421), its alate portion (blade) 0.183 (0.0.159–0.196) long. Right spicule 0.092 (0.087–0.101) long, relatively stout, with dorsal projecting barb at distal end and a bulbous, convex proximal end (Fig. 50 B). Length ratio of right to left spicule 1:3.93 to 1:4.22. Tail 0.306 (0.266–0.365) long, tapering and ending in a rounded tip (Fig. 50 A). Female paratypes (means with ranges in parentheses): body 10.6 (8.9–13.4), prostom 0.026 (0.023–0.028), vestibule 0.107 (0.097–0.120), muscular oesophagus 0.278 (0.261–0.290) and glandular oesophagus 2.27 (2.08– 2.54) long. Deirids 0.066 (0.060–0.076), nerve ring 0.158 (0.146–0.179) and excretory pore 0.233 (0.212–0.265) from anterior end. Vulva located near midpoint of body, 6.0 (4.9–7.3) from anterior end. Phasmids minute, posterior to midpoint of tail. Eggs ovoid, smooth, without filaments or floats, 0.023 (0.023–0.024) x 0.038 (0.036– 0.039). Tail 0.215 (0.188–0.241) long, tapering and ending in a rounded tip (Fig. 50 C). Note: Byrne (op. cit.) also provided measurements for the male holotype and female allotype of R. rotundicaudatum. Site: intestine Hosts: Ambloplites rupestris (1, 2); Ameiurus nebulosus (1, 2); Etheostoma caeruleum (1, 2); Luxilus cornutus (1, 2); Nocomis biguttatus (1, 2); Nocomis micropogon (2); Semotilus atromaculatus (1, 2) Distribution: Ontario Records: 1. Byrne 1992 a (ON); 2. Byrne 1992b (EX, ON), Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on page 79, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530, {"references":["Byrne, P. J. (1992 a) Rhabdochona rotundicaudatum n. sp. and a redescription of R. cascadilla Wigdor, 1918 (Nematoda: Thelazioidea) from minnows in southern Ontario, Canada. Canadian Journal of Zoology, 70, 476 - 484. http: // dx. doi. org / 10.1139 / z 92 - 072","Byrne, P. J. (1992 b) On the biology of Rhabdochona rotundicaudatum and R. cascadilla (Nematoda: Thelazioidea) in stream fishes from southern Ontario, Canada. Canadian Journal of Zoology, 70, 485 - 493. http: // dx. doi. org / 10.1139 / z 92 - 073"]}

Rhabdochona canadensis Moravec & Arai, 1971 Description (after Moravec & Arai 1971). With characteristics of the genus. Males (holotype measurements in parentheses): 5.74–8.36 (8.32) long, 0.109–0.150 (0.122) maximum width. Pseudolabia rudimentary. Prostom conspicuously wide, funnel-shaped, without basal teeth, 0.015–0.021 (0.021) long, 0.012–0.015 maximum width. Prostom lined internally with 14 longitudinal ridges, forming small teeth at their anterior ends (Fig. 42 A,B). Vestibule including prostom 0.120–0.165 (0.165), muscular oesophagus 0.186– 0.306 (0.216), and glandular oesophagus 2.18–3.90 (3.90) long. Small, bifurcate deirids 0.051–0.069 (0.069), nerve ring 0.177–0.207 (0.198), and excretory pore 0.237–0.279 (not located in holotype) from anterior end. Subventral pre-cloacal papillae asymmetrical in holotype (nine on one side, and seven on the other); the following combinations were seen in paratypes: 7+7, 7+9, 8+8 and 9+9 (Fig. 42 C). Additional pair of lateral pre-cloacal papillae at level of 3rd subventral pair (counted from cloaca). Six pairs of post-cloacal papillae: five subventral and one lateral (Fig. 42 C). Left spicule conspicuously slender, 0.471–0.525 (0.495) long and 0.06–0.09 wide at midlength [the figures for width from Moravec et al. 1981], with blade representing about the posterior half; distal tip lanceolate and thin, with cuticular membrane, bifurcate (Fig. 42 D). Right spicule 0.102–0.129 (0.126) long, with dorsally reflected barb distally. Length ratio of right to left spicule 1:3.86 to 1:5.14 (1:3.91). Tail conical, 0.270–0.390 (0.390) long, with sharp terminal spike (Fig. 42 C). Females (allotype measurements in parentheses): gravid worms 9.88–27.92 (14.84) long, 0.190–0.408 (0.245) maximum width. Prostom wide, 0.021–0.033 (0.030) long. Vestibule including prostom 0.144–0.195 (0.186), muscular oesophagus 0.300–0.510 (0.480), and glandular oesophagus 3.26–5.07 (4.52) long. Deirids 0.063–0.078 (0.072), nerve ring 0.219–0.270 (0.237), and excretory pore 0.351–0.420 (0.369) from anterior end. Tail conical, 0.216–0.309 (0.231) long, terminating in sharp spike. Vulva post-equatorial, 4.27–13.15 (5.90) from posterior end of body. Mature eggs oval, embryonated, 0.036–0.042 x 0.018– 0.021 (0.036–0.042 x 0.018–0.021), with one or two long filaments on each pole. Fully mature eggs usually with two filaments on one pole and only one filament on the other pole (Fig. 42 E); however, often two filaments on both poles. Filaments very long (ca 0.6) with relatively wide bases and ends sometimes frayed. Site: intestine Hosts: Catostomus commersonii (10, 11); Cottus sp. (5); Couesius plumbeus (1, 8); Esox lucius (1); Hiodon alosoides (10, 11); Margariscus margarita (9); Moxostoma anisurum (10, 11); Noturus flavus (1); Oncorhynchus mykiss (3, 5); Percopsis omiscomaycus (10, 11); Chrosomus eos (9, 12); Phoxinus neogaeus (9); Platygobio gracilis (1); Rhinichthys cataractae (1, 6, 7); Salvelinus malma (2, 4); Sander vitreus (1); Semotilus atromaculatus (9); Semotilus corporalis (9) Distribution: Alberta, British Columbia, Manitoba, Ontario Records: 1. Moravec & Arai 1971 (AB); 2. Anon. 1978 (BC); 3. Pybus & Samuel 1978 (AB); 4. Arai & Mudry 1983 (BC); 5. McAllister & Mudry 1983 (AB); 6. Dechtiar & Christie 1988 (ON); 7. Dechtiar & Lawrie 1988 (ON); 8. Dechtiar et al. 1988 (ON); 9. Dechtiar et al. 1989 (ON); 10. Szalai 1989 (MB); 11. Szalai et al. 1992 (MB); 12. Marcogliese et al. 2001 (ON), Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on page 68, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530, {"references":["Moravec, F. & Arai, H. P. (1971) The North and Central American species of Rhabdochona (Nematoda: Rhabdochonidae) of fishes, including Rhabdochona canadensis sp. nov. Journal of the Fisheries Research Board of Canada, 28, 1645 - 1662. http: // dx. doi. org / 10.1139 / f 71 - 245","Pybus, M. J. & Samuel, W. M. (1978) Summary of field trips ̶ Wildlife Parasitology class, University of Alberta. Department of Zoology, University of Alberta, Edmonton, Alberta. Unpublished Report.","McAllister, D. J. & Mudry, D. R. (1983) Diseases and Parasites of Alberta Fishes and Potential Consequences of their Interbasin Transfer. Prepared for the Alberta Environmental Research Trust by Techman Inc., Calgary, Alberta, 80 pp.","Dechtiar, A. O. & Christie, W. J. (1988) Survey of the parasite fauna of Lake Ontario fishes, 1961 to 1971. In: Nepszy, S. J. (Ed.), Parasites of Fishes in the Canadian waters of the Great Lakes. Great Lakes Fishery Commission, Technical Report, No. 51, 66 - 95.","Dechtiar, A. O. & Lawrie, A. H. (1988) Survey of the parasite fauna of Lake Superior fishes, 1969 to 1975. In: Nepszy, S. J. (Ed.), Parasites of Fishes in the Canadian waters of the Great Lakes. Great Lakes Fishery Commission, Technical Report, No. 51, 1 - 18.","Dechtiar, A. O., MacLean, J. A. & Nepszy, S. J. (1989) Parasites of Fishes from Algonquin Park lakes. Ontario Fisheries, Technical Report. Series, No. 29, 10 pp.","Marcogliese, D. J., Ball, B. & Lankester, M. W. (2001) Potential impacts of clearcutting on parasites of minnows in small boreal lakes. Folia Parasitologica, 48, 269 - 274. http: // dx. doi. org / 10.14411 / fp. 2001.045"]}

Rhabdochona cascadilla Wigdor, 1918 Synonyms: Rhabdochona sp. of Bangham (1941 partim); Rhabdochona sp. of Bangham & Venard (1946 partim) Description (after Byrne 1992a). With characteristics of the genus. General characteristics: outer circle of four cephalic papillae and inner circle of four labial papillae present. Prostom armed with 14 longitudinal sclerotized rods projecting anteriorly as teeth, of which three are dorsal, three ventral, two pairs ventro-lateral, and two pairs dorso-lateral. Sclerotized protuberances present in basal part of prostom [= basal teeth?]. Deirids small, bifurcate, located about the midpoint of vestibule. Male paratypes (means with ranges in parentheses): body 4.5 (4.0–5.1), prostom 0.016 (0.012–0.019), vestibule 0.076 (0.068–0.085), muscular oesophagus 0.159 (0.146–0.227) and glandular oesophagus 1.1 (0.8–1.8) long. Deirids 0.047 (0.039–0.054), nerve ring 0.124 (0.118–0.134) and excretory pore 0.198 (0.182–0.210) from anterior end. Caudal papillae digitiform: 14 to 19 pre-cloacal and 12 (six pairs) post-cloacal, mostly subventral. Phasmids minute, located just distal to most posterior pair of caudal papillae. Left spicule 0.378 (0.320–0.415), its alate portion (blade) 0.171 (0.153–0.190) long. Right spicule 0.118 (0.103–0.128) long, with dorsally projecting barb at distal end, and a bulbous, convex proximal end. Length ratio of right to left spicule 1:3.20 (1:3.11 to 1:3.24). Tail 0.277 (0.212–0.322) long, tapering and ending in pointed tip (Fig. 43 A,B). Female paratypes (means with ranges in parentheses): body 8.4 (6.4–9.9), prostom 0.024 (0.019–0.027), vestibule 0.089 (0.076–0.097), muscular oesophagus 0.198 (0.175–0.227) and glandular oesophagus 1.4 (1.1–1.6) long. Deirids 0.055 (0.050–0.062), nerve ring 0.147 (0.134–0.159) and excretory pore 0.235 (0.200–0.266) from anterior end (Fig. 43 C,D). Vulva near midpoint of body, 4.4 (3.5–5.0) from anterior end (Fig. 43 E). Phasmids minute, posterior to midpoint of tail. Eggs ovoid, smooth, without filaments or floats (Fig. 43 F), 0.017 (0.017– 0.019) x 0.033 (0.031–0.034). Tail 0.228 (0.184–0.287) long, tapering and ending in pointed tip. Comments: the 41 fish species listed below have been reported as hosts of R. cascadilla in Canada. However, according to Byrne (1992a) the numerous reports of this rhabdochonid species “across much of Canada and the United States, from at least 64 species of fish (Byrne 1989) should be accepted with reservation”. Site: intestine Hosts: Acipenser fulvescens (7, 20, 22); Acrocheilus alutaceus (6); Ambloplites rupestris (1); Ameiurus nebulosus (4); Carpiodes cyprinus (1); Catostomus catostomus (6, 10, 13); Catostomus commersonii (4, 9, 10, 13); Catostomus macrocheilus (6); Couesius plumbeus (6); Culaea inconstans (17); Cyprinella spiloptera (1); Etheostoma exile (5, 7, 8); Etheostoma nigrum (5, 7, 8); Hiodon tergisus (1); Lota lota (8); Luxilus cornutus (2, 3, 5, 7, 16, 17, 18, 19); Margariscus margarita (2, 3, 4); Micropterus dolomieu (3); Moxostoma macrolepidotum (1); Mylocheilus caurinus (6, 12, 14); Nocomis biguttatus (18, 19); Notemigonus crysoleucas (23); Notropis anogenus (8); Notropis hudsonius (1, 5, 7, 8); Notropis stramineus (1); Notropis volucellus (1); Oncorhynchus clarkii (6); Oncorhynchus mykiss (6); Oncorhynchus nerka (6, 9, 17); Perca flavescens (9); Percopsis omiscomaycus (9); Chrosomus eos (3, 21); Prosopium williamsoni (6); Pimephales notatus (3, 5, 7); Ptychocheilus oregonensis (6, 12, 14); Rhinichthys atratulus (8); Rhinichthys cataractae (6); Richardsonius balteatus (6, 12, 14); Salvelinus fontinalis (4, 11); Semotilus atromaculatus (2, 3, 4, 5, 7, 15, 17); Semotilus corporalis (3) Distribution: Alberta, British Columbia, Hudson Bay Drainage, Manitoba, Nova Scotia, Ontario, Quebec Records: 1. Bangham & Hunter 1939 (ON); 2. Bangham 1941 (ON); 3. Bangham & Venard 1946 (ON); 4. Choquette 1951a (QC); 5. Bangham 1951 (ON); 6. Bangham & Adams 1954 (BC); 7. Bangham 1955 (ON); 8. Dechtiar 1972a (ON); 9. Collins & Dechtiar 1974 (ON); 10. Leong 1975 (AB); 11. Mudry & Anderson 1977 (AB); 12. Anon. 1978 (BC); 13. Leong & Holmes 1981 (AB); 14. Arai & Mudry 1983 (BC); 15. Mackie et al. 1983 (ON); 16. Byrne & Baker 1987 (ON); 17. Dechtiar et al. 1988 (ON); 18. Byrne 1992a (ON); 19. Byrne 1992b (ON); 20. Choudhury & Dick 1993 (MB); 21. Dubois et al. 1996 (QC); 22. Choudhury & Dick 1998 (HBD, MB); 23. Forest & Cone 2011 (NS), Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on pages 68-70, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530, {"references":["Bangham, R. V. (1941) Parasites of fish of Algonquin Park lakes. Transactions of the American Fisheries Society, 70, 161 - 171. http: // dx. doi. org / 10.1577 / 1548 - 8659 (1940) 70 [161: pofoap] 2.0. co; 2","Bangham, R. V. & Venard, C. E. (1946) Parasites of fish of Algonquin Park lakes. II. Distribution studies. University of Toronto Studies in Biology Series, 53, 31 - 46. (Ontario Fisheries Research Laboratory Publication. No. 65.)","Byrne, P. J. (1992 a) Rhabdochona rotundicaudatum n. sp. and a redescription of R. cascadilla Wigdor, 1918 (Nematoda: Thelazioidea) from minnows in southern Ontario, Canada. Canadian Journal of Zoology, 70, 476 - 484. http: // dx. doi. org / 10.1139 / z 92 - 072","Byrne, P. J. (1989) Transmission and epizootiology of two Rhabdochona spp. (Thelazioidea) in stream fishes in southern Ontario. M. Sc. Thesis, Department of Zoology, University of Guelph, Guelph, Ontario.","Bangham, R. V. & Hunter, G. W. III. (1939) Studies on fish parasites of Lake Erie. Distribution studies. Zoologica (New York), 24, 385 - 444.","Choquette, L. P. E. (1951 a) On the nematode genus Rhabdochona Railliet, 1916 (Nematoda: Spiruroidea). Canadian Journal of Zoology, 29, 1 - 16. http: // dx. doi. org / 10.1139 / z 51 - 001","Bangham, R. V. (1951) Parasite records by location in 1951: Manitoulin Island and surrounding waters. University of Toronto, Ontario Fisheries Research Laboratory Report, 27 pp.","Bangham, R. V. & Adams, J. R. (1954) A survey of the parasites of freshwater fishes from the mainland of British Columbia. Journal of the Fisheries Research Board of Canada, 11, 673 - 708. http: // dx. doi. org / 10.1139 / f 54 - 043","Bangham, R. V. (1955) Studies on fish parasites of Lake Huron and Manitoulin Island. American Midland Naturalist, 53, 184 - 194. http: // dx. doi. org / 10.2307 / 2422308","Dechtiar, A. O. (1972 a) Parasites of fish from Lake of the Woods, Ontario. Journal of the Fisheries Research Board of Canada, 29, 275 - 283. http: // dx. doi. org / 10.1139 / f 72 - 046","Collins, J. J. & Dechtiar, A. O. (1974) Parasite fauna of kokanee salmon (Oncorhynchus nerka) introduced into Lake Huron. Journal of the Fisheries Research Board of Canada, 31, 1818 - 1821. http: // dx. doi. org / 10.1139 / f 74 - 234","Leong, T. S. (1975) Metazoan parasites of fishes of Cold Lake, Alberta: a community analysis. Ph. D. Dissertation. Department of Zoology, University of Alberta, Edmonton, Alberta, 170 pp.","Mudry, D. R. & Anderson, R. S. (1977) Helminth and arthropod parasites of freshwater fishes in Alberta, 1932 - 1975. Journal of Fish Biology, 11, 21 - 33. http: // dx. doi. org / 10.1111 / j. 1095 - 8649.1977. tb 04095. x","Leong, T. S. & Holmes, J. C. (1981) Communities of metazoan parasites in open water fishes of Cold Lake, Alberta. Journal of Fish Biology, 18, 693 - 713. http: // dx. doi. org / 10.1111 / j. 1095 - 8649.1981. tb 03811. x","Arai, H. P. & Mudry, D. R. (1983) Protozoan and metazoan parasites of fishes from the headwaters of the Parsnip and McGregor Rivers, British Columbia: a study of possible parasite transfaunations. Canadian Journal of Fisheries and Aquatic Sciences, 40, 1676 - 1684. http: // dx. doi. org / 10.1139 / f 83 - 194","Mackie, G. L., Morton, W. B. & Ferguson, M. S. (1983) Fish parasitism in a new impoundment and differences upstream and downstream. Hydrobiologia, 99, 197 - 205. http: // dx. doi. org / 10.1007 / bf 00008771","Byrne, P. J. & Baker, M. R. (1987) The biology of Rhabdochona cascadilla Wigdor, 1918 (Nematoda: Spirurida) in the common shiner from a southern Ontario stream. Program and Abstracts. 26 th Annual Meeting, Canadian Society of Zoologists, McGill University, 13 - 15 May 1987. Bulletin of the Canadian Society of Zoologists, 18, p. 22.","Byrne, P. J. (1992 b) On the biology of Rhabdochona rotundicaudatum and R. cascadilla (Nematoda: Thelazioidea) in stream fishes from southern Ontario, Canada. Canadian Journal of Zoology, 70, 485 - 493. http: // dx. doi. org / 10.1139 / z 92 - 073","Choudhury, A. & Dick, T. A. (1993) Parasites of the lake sturgeon, Acipenser fulvescens (Chondrostei: Acipenseridae), from central Canada. Journal of Fish Biology, 42, 571 - 584. http: // dx. doi. org / 10.1006 / jfbi. 1993.1060","Dubois, N., Marcogliese, D. J. & Magnan, P. (1996) Effects of the introduction of white sucker, Catostomus commersoni, on the parasite fauna of brook trout, Salvelinus fontinalis. Canadian Journal of Zoology, 74, 1304 - 1312. http: // dx. doi. org / 10.1139 / z 96 - 146","Choudhury, A. & Dick, T. A. (1998) Patterns and determinants of helminth communities in the Acipenseridae (Actinopterygii: Chondrostei), with special reference to the lake sturgeon, Acipenser fulvescens. Canadian Journal of Zoology, 76, 330 - 349. http: // dx. doi. org / 10.1139 / z 97 - 189","Forest, J. J. H. & Cone, D. K. (2011) Helminth parasites of golden shiner Notemigonus crysoleucas (Pisces: Cyprinidae) from Ontario and Nova Scotia, Canada. Comparative Parasitology, 78, 220 - 222. http: // dx. doi. org / 10.1654 / 4442.1"]}

Rhabdochona cotti Gustafson, 1949 Description (after Gustafson 1949, and Moravec & Arai 1971). With characteristics of the genus. Slender worms, attenuated at both ends. Pseudolabia rudimentary. Prostom funnel-shaped, without basal teeth, with 14 teeth projecting anteriorly from longitudinal ridges. Oesophagus comparatively short, divided into anterior muscular and posterior glandular portions. Deirids small (“shape of deirids not determined”), lateral, opposite mid-portion of buccal cavity. Males (measurements of paratypes according to Moravec & Arai (1971) in parentheses): 7.65–10.6 (12.76) long, 0.080–0.131 (0.154) maximum width. Prostom 0.017–0.020 (0.015), “total stoma” 0.082–0.122 (vestibule including prostom 0.093–0.096), muscular oesophagus 0.272–0.340 (0.252–0.285), and glandular oesophagus 0.80–1.28 (0.87–1.22) long. Nerve ring 0.17–0.22 (0.165–0.195) and excretory pore 0.22–0.32 (0.216) from anterior end. Left spicule 0.309–0.370 (0.354–0.357) long, of which 0.163–0.197 is the alate portion; according to Moravec & Arai (op. cit.) its distal tip appears “lanceolate and similar to that of R. canadensis ” (see above). Right spicule 0.085–0.120 (0.102–0.105) long, scoop-shaped, with rounded posterior end lacking distinct barb distally. Length ratio of right to left spicule 1:3.08 to 1:–3.64. About eight pairs of pre-cloacal papillae, all subventral except for the 3rd sublateral pair anterior to cloaca. Six pairs of post-cloacal papillae, of which the 2nd pair is is sublateral and the others subventral. Tail conical, 0.285–0.294 long, with distinctly rounded tip, without cuticular spike (Fig. 45 A). Females (measurements of paratypes according to Moravec & Arai (1971) in parentheses): 18.3–34.2 (19.20– 29.48) long, 0.19–0.31 (0.258–0.462) maximum width. Prostom 0.025–0.036 (0.024–0.027), “total stoma” 0.102– 0.143 (vestibule including prostom 0.099–0.111) [Fig. 45 B], muscular oesophagus 0.374–0.626 (0.330), glandular oesophagus 1.46–1.92 (not determined) long. Nerve ring 0.21–0.43, excretory pore 0.305–0.580, and vulva 11.4– 20.9 from anterior end. Tail 0.204–0.350 (0.210–0.300) long, conical with distinct rounded tip, without cuticular spike (Fig. 45 C). Eggs embryonated when laid, 0.032–0.033 x 0.018–0.020, with two long single (rarely double) filaments. Site: intestine Hosts: Cottus asper (1); Cottus bairdii (2, 6, 7); Cottus cognatus (1, 3, 4, 5, 8); Cottus caeruleomentum (9) Distribution: Alberta, British Columbia, Ontario Records: 1. Bangham & Adams 1954 (BC); 2. Dechtiar 1972a (ON); 3. Mudry & Anderson 1977 (AB); 4. Anon. 1978 (BC); 5. Arai & Mudry 1983 (BC); 6. Dechtiar et al. 1988 (ON); 7. Dechtiar & Lawrie 1988 (ON); 8. Dechtiar et al. 1989 (ON); 9. Moravec & Muzzall 2007 (BC), Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on pages 71-73, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530, {"references":["Moravec, F. & Arai, H. P. (1971) The North and Central American species of Rhabdochona (Nematoda: Rhabdochonidae) of fishes, including Rhabdochona canadensis sp. nov. Journal of the Fisheries Research Board of Canada, 28, 1645 - 1662. http: // dx. doi. org / 10.1139 / f 71 - 245","Bangham, R. V. & Adams, J. R. (1954) A survey of the parasites of freshwater fishes from the mainland of British Columbia. Journal of the Fisheries Research Board of Canada, 11, 673 - 708. http: // dx. doi. org / 10.1139 / f 54 - 043","Dechtiar, A. O. (1972 a) Parasites of fish from Lake of the Woods, Ontario. Journal of the Fisheries Research Board of Canada, 29, 275 - 283. http: // dx. doi. org / 10.1139 / f 72 - 046","Mudry, D. R. & Anderson, R. S. (1977) Helminth and arthropod parasites of freshwater fishes in Alberta, 1932 - 1975. Journal of Fish Biology, 11, 21 - 33. http: // dx. doi. org / 10.1111 / j. 1095 - 8649.1977. tb 04095. x","Arai, H. P. & Mudry, D. R. (1983) Protozoan and metazoan parasites of fishes from the headwaters of the Parsnip and McGregor Rivers, British Columbia: a study of possible parasite transfaunations. Canadian Journal of Fisheries and Aquatic Sciences, 40, 1676 - 1684. http: // dx. doi. org / 10.1139 / f 83 - 194","Dechtiar, A. O. & Lawrie, A. H. (1988) Survey of the parasite fauna of Lake Superior fishes, 1969 to 1975. In: Nepszy, S. J. (Ed.), Parasites of Fishes in the Canadian waters of the Great Lakes. Great Lakes Fishery Commission, Technical Report, No. 51, 1 - 18.","Dechtiar, A. O., MacLean, J. A. & Nepszy, S. J. (1989) Parasites of Fishes from Algonquin Park lakes. Ontario Fisheries, Technical Report. Series, No. 29, 10 pp.","Moravec, F. & Muzzall, P. (2007) Redescription of Rhabdochona cotti (Nematoda, Rhabdochonidae) from Cottus caeruleomentum (Teleostei, Cottidae) in Maryland, USA, with remarks on the taxonomy of North American Rhabdochona spp. Acta Parasitologica, 52, 5 - 57. http: // dx. doi. org / 10.2478 / s 11686 - 006 - 0049 - x"]}

Rhabdochona decaturensis Gustafson, 1949 Description (after Gustafson 1949, and Moravec & Arai 1971). With characteristics of the genus. Small, slender, worms, attenuated at both ends. Pseudolabia rudimentary. Buccal cavity heavily sclerotized, funnel-shaped prostom containing 14 minute teeth projecting anteriorly from longitudinal ridges; four minute teeth at base of prostom (Fig. 46 A). Oesophagus relatively long, divided into anterior muscular and posterior glandular portions. Deirids very small, simple, lateral, opposite mid-portion of buccal cavity. Males (measurements of a paratype according to Moravec & Arai (1971) in parentheses): 6.8–8.0 long (13.29), 0.085–0.100 (0.132) maximum width. Prostom 0.015–0.017 (0.018), “total stoma” 0.096–0.110 (vestibule including prostom 0.120), muscular oesophagus 0.21–0.27 (0.255), glandular oesophagus 1.70–2.0 (3.52), and tail 0.25–0.31 (0.296) long, with terminal cuticular spike. Nerve ring 0.140–0.170 (0.180) and excretory pore 0.210– 0.250 (0.273) from anterior end. Left spicule relatively long at 0.830–1.025 (1.074), with conical distal tip, not bifurcated; spicule shaft representing 73% of entire length. Right spicule 0.075–0.100 (0.090) long, scoop-shaped, with reflected barb near tip on left side. Length ratio of right to left spicule 1:10.25 to 1:11.93. About eight (seven) pairs of pre-cloacal papillae, of which seven pairs are subventral, and one pair sublateral. Six (six) pairs of postcloacal papillae, of which the 2nd pair is sublateral, the others subventral (Fig. 46 B). Females (measurements of a paratype according to Moravec & Arai (1971) in parentheses): 9.2–13.4 (21.25) long, 0.093–0.160 (0.198) maximum width. Prostom 0.016–0.025 (0.024), “total stoma” 0.090–0.110 (vestibule including prostom 0.120), muscular oesophagus 0.217–0.320 (0.299), glandular oesophagus 1.92–2.6 (4.38), and tail 0.16–0.23 long (0.165) with cuticular terminal spike (Fig. 46 C). Nerve ring 0.150–0.170 (0.183) and excretory pore 0.236–0.257 (0.270) from anterior end. Eggs embryonated when laid, ovoid, 0.031–0.038 x 0.015–0.023, bearing no filaments. Site: intestine Hosts: Luxilus cornutus (2, 3); Notropis hudsonius (1, 2, 3); Noturus flavus (1); Noturus gyrinus (1) Distribution: Ontario Records: 1. Dechtiar & Christie 1988; 2. Dechtiar & Lawrie 1988; 3. Dechtiar et al. 1988, Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on page 73, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530, {"references":["Moravec, F. & Arai, H. P. (1971) The North and Central American species of Rhabdochona (Nematoda: Rhabdochonidae) of fishes, including Rhabdochona canadensis sp. nov. Journal of the Fisheries Research Board of Canada, 28, 1645 - 1662. http: // dx. doi. org / 10.1139 / f 71 - 245","Dechtiar, A. O. & Christie, W. J. (1988) Survey of the parasite fauna of Lake Ontario fishes, 1961 to 1971. In: Nepszy, S. J. (Ed.), Parasites of Fishes in the Canadian waters of the Great Lakes. Great Lakes Fishery Commission, Technical Report, No. 51, 66 - 95.","Dechtiar, A. O. & Lawrie, A. H. (1988) Survey of the parasite fauna of Lake Superior fishes, 1969 to 1975. In: Nepszy, S. J. (Ed.), Parasites of Fishes in the Canadian waters of the Great Lakes. Great Lakes Fishery Commission, Technical Report, No. 51, 1 - 18."]}

Rhabdochona catostomi Kayton, Kritsky & Tobias, 1979 Description (after Kayton et al. 1979). With characteristics of the genus. Body filiform, males smaller than females. Caudal end conical with terminal spike. Mouth with two bilateral rudimentary pseudolabia, two large bilateral amphids, outer circle of cephalic papillae (inner circle apparently absent). Prostom funnel-shaped, lacking basal teeth, its inner wall with 10 longitudinal cuticular ridges terminating in anterior teeth. Cuticle lines entire vestibule. Oesophagus with anterior muscular and wider posterior glandular regions. Deirids small, bifurcate, lying slightly anterior to mid-vestibule. Males: body 8.9–14.3 long, 0.173–0.211 maximum width. Prostom 0.022–0.034, vestibule 0.134–0.174, muscular oesophagus 0.336–0.372, and glandular oesophagus 3.5–4.8 long. Deirids 0.076–0.085, nerve ring 0.204–0.238, and excretory pore 0.484 from anterior end. Tail 0.336–0.392 long, curved ventrally. Caudal alae absent. Subventral caudal papillae variable in number, 8 or 9 pre-cloacal, and 5 post-cloacal pairs (Fig. 44 A). Left spicule 0.546–0.562 long, slender, with ventral groove, its tip with ventral barb, bifurcate. Right spicule 0.151– 0.154 long, with reflected distal barb (Fig. 44 B). Length ratio of right to left spicule 1:3.62 to 1:3.65. Females: body 15.3–16.7 long, 0.248–0.292 maximum width. Prostom 0.028–0.031, vestibule 0.154–0.176, muscular oesophagus 0.375–0.417, and glandular oesophagus 4.97–6.10 long. Deirids 0.090–0.097 and nerve ring 0.227–0.284 from anterior end [position of excretory pore not stated]. Tail 0.227–0.280 long, usually straight (Fig. 44 C). Vulva post-equatorial comprising a transverse slit surrounded by elevated labia. Mature eggs ellipsoidal, embryonated, “poles usually with complex elongate filaments”, measuring 0.031–0.036 x 0.020–0.024 (Fig. 44 D). Site: intestine Host: Catostomus catostomus Distribution: Alberta Record: Kayton et al. 1979, Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on page 70, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530, {"references":["Kayton, R. J., Kritsky, D. C. & Tobias, R. C. (1979) Rhabdochona catostomi sp. n. (Nematoda: Rhabdochonidae) from the intestine of Catostomus spp. (Catostomidae). Proceedings of the Helminthological Society of Washington, 46, 224 - 227."]}

** Rhabdochona sp. Site: intestine Hosts: Ambloplites rupestris (1, 17); Ameiurus melas (6); Ameiurus nebulosus (2, 21); Catostomus catostomus (9, 11, 14, 23); Catostomus commersonii (2, 3, 9); Catostomus macrocheilus (11, 14); Coregonus clupeaformis (3); Cottus cognatus (11, 14); Couesius plumbeus (5, 7); Etheostoma caeruleum (17, 21); Etheostoma exile (19); Fundulus diaphanus (1); Lepomis gibbosus (2, 3); Lepomis macrochirus (1); Luxilus cornutus (16, 20, 21); Micropterus dolomieu (6); Morone chrysops (1); Mylocheilus caurinus (14, 15); Nocomis biguttatus (21); Notemigonus crysoleucas (17, 20); Notropis atherinoides (21); Notropis hudsonius (4); Oncorhynchus kisutch (6, 13, 15); Oncorhynchus mykiss (11, 13, 14); Oncorhynchus nerka (8); Oncorhynchus tshawytscha (13, 14, 15); Perca flavescens (2, 5, 7, 10); Percopsis omiscomaycus (18); Pimephales promelas (3); Prosopium williamsoni (11, 13, 14, 15, 22); Ptychocheilus oregonensis (11, 14, 15); Richardsonius balteatus (11, 14); Salvelinus fontinalis (6); Salvelinus fontinalis x Salvelinus namyacush (12); Salvelinus malma (11, 13, 14, 15); Semotilus atromaculatus (21) Distribution: Alberta, British Columbia, Labrador, Manitoba, Ontario Records: 1. Bangham & Hunter 1939 (ON); 2. Bangham 1941 (ON); 3. Bangham & Venard 1946 (ON); 4. Stewart- Hay 1951c (MB); 5. Bangham 1951 (ON); 6. Bangham & Adams 1954 (BC); 7. Bangham 1955 (ON); 8. Margolis 1957 (BC); 9. Threlfall & Hanek 1970a (LB); 10. Mudry & Anderson 1977 (AB); 11. Anon. 1978 (BC); 12. Dechtiar & Berst 1978 (ON); 13. Anon. 1981 (BC); 14. Arai & Mudry 1983 (BC); 15. Anon. 1984 (BC); 16. Byrne & Baker 1987 (ON); 17. Dechtiar & Christie 1988 (ON); 18. Dechtiar & Lawrie 1988 (ON); 19. Dechtiar et al. 1988 (ON); 20. Dechtiar et al. 1989 (ON); 21. Byrne 1992b (ON); 22. Nener et al. 1995 (BC); 23. Baldwin & Goater 2003 (AB)

Key to species of Rhabdochona According to Moravec et al. (1981) the closest relative of R. zacconis Yamaguti, 1935 is probably R. canadensis Moravec & Arai, 1971; the two species “differ distinctly only in the position of the deirids (more anterior relative to length of the vestibule in R. canadensis) and the shape of the distal end and width of the left spicule”. There is possible confusion here because Moravec & Arai (1971) stated that the left spicule of R. canadensis is “conspicuously slender” but, at a width of 0.06–0.09 (see Moravec et al., 1981), it is not as slender as that of R. zacconis at 0.012–0.015. For these reasons the following key does not attempt to distinguish the two species (although separate descriptions are given). It is relevant to point out that neither Anon. (1978) nor Arai & Mudry (1983) described or illustrated the worms from Catostomus macrocheilus in British Columbia that they claimed represented R. zacconis. This species has not been previously reported from North America so it is possible that the worms represented R. canadensis rather than R. zacconis. 1 Mature eggs smooth, without filaments or gelatinous “formations”............................................. 2 - Mature eggs with gelatinous “formations”, mostly in the shape of polar caps, or filaments............................ 4 2 Left spicule longer than 0.8; length ratio of right to left spicule 1:10.2 to 1:11.9.......................... R. decaturensis - Left spicule shorter than 0.6; length ratio of right to left spicule 1:3.1 to 1:4.2..................................... 3 3 Right spicule with truncated proximal end; tail ends in rounded tip............................... R. rotundicaudatum - Right spicule with bulbous, convex proximal end; tail ends in sharp point............................... R. cascadilla 4 Prostom with 16 teeth; egg surfaces covered with fine protuberances and numerous short filaments.......... R. ovifilamenta - Prostom with 10 or 14 teeth............................................................................ 5 5 Prostom with 10 teeth................................................................................. 6 - Prostom with 14 teeth................................................................................. 7 6 Prostom lacks basal teeth; deirids small, bifurcate................................................. R. catostomi - Prostom with basal teeth; deirids medium-sized, bifurcate; eggs with gelatinous “formations” covering most of poles and lat- eral surfaces................................................................................. R. kisutchi 7 Tail tip rounded; eggs with two long single, rarely double, filaments; parasitic in Cottidae....................... R. cotti - Tail ends in sharp point............................................................................... 8 8 Both egg poles with numerous fine filaments........................................................ R. milleri - Both egg poles with at least one filament, sometimes two filaments on one or both poles......... R. canadensis / R. zacconis, Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on pages 66-67, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530, {"references":["Yamaguti, S. (1935) Studies on the helminth fauna of Japan. Part 9. Nematodes of fishes, I. Japanese Journal of Zoology, 6, 337 - 386. http: // dx. doi. org / 10.1017 / s 0022149 x 00017788","Moravec, F. & Arai, H. P. (1971) The North and Central American species of Rhabdochona (Nematoda: Rhabdochonidae) of fishes, including Rhabdochona canadensis sp. nov. Journal of the Fisheries Research Board of Canada, 28, 1645 - 1662. http: // dx. doi. org / 10.1139 / f 71 - 245","Arai, H. P. & Mudry, D. R. (1983) Protozoan and metazoan parasites of fishes from the headwaters of the Parsnip and McGregor Rivers, British Columbia: a study of possible parasite transfaunations. Canadian Journal of Fisheries and Aquatic Sciences, 40, 1676 - 1684. http: // dx. doi. org / 10.1139 / f 83 - 194"]}

Rhabdochona Railliet, 1916 Generic diagnosis (after Moravec 2013). Rhabdochonidae. Medium sized nematodes. Pseudolabia rudimentary. Vestibule dilated to form well-defined funnel- or barrel-shaped prostom supported by longitudinal thickenings projecting anteriorly as teeth, variable in number. Deirids simple or bifurcate. Lateral alae present or absent. Oesophagus divided into anterior muscular portion and posterior glandular portion. Males: many pre-cloacal and five to seven post-cloacal pairs of papillae; no caudal alae; spicules unequal and dissimilar; gubernaculum absent; tail conical, its tip rounded or with sharp point, rarely with several minute digital processes. Females: amphidelphic; vulva about mid-body, tail tip rounded or with sharp point, sometimes with many spines, spikes or small mucronate points; eggs elliptical, embryonated, their shells smooth, filamented or with swellings (“formations”). Parasitic in intestine of fresh-water fishes., Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on page 66, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530

Rhabdochona zacconis Yamaguti, 1935 Description (after Moravec, Margolis & Boyce 1981). With characteristics of the genus. Medium-sized worms with smooth cuticle. Mouth approximately hexagonal, slightly compressed dorso-ventrally, surrounded by two large lateral amphids and four small sub-apical papillae. Prostom thick-walled, funnel-shaped, without basal teeth but with 14 teeth projecting anteriorly. Deirids medium-sized, bifurcate, located posterior to middle of vestibule (Fig. 51 A). Tail of both sexes conical, ending in sharp point (Fig. 51 B,E). Males: body 6.69–10.06 long, 0.122–0.177 maximum width. Prostom 0.018–0.021, vestibule including prostom 0.135–0.207, muscular oesophagus 0.279–0.390 and glandular oesophagus 2.45–4.90 long. Deirids 0.075–0.090, nerve ring 0.192–0.237 and excretory pore 0.303 from anterior end. Pairs of subventral pre-cloacal papillae variable in number; the following combinations were observed: 7+8, 8+9 and 9+9. Another pair was located laterally at level of 3rd subventral pair. Six pairs of post-cloacal papillae present, the 2nd pair lateral, the rest subventral (Fig. 51 B). Longitudinal ventral cuticular ridges anterior to pre-cloacal papillae well developed. Left spicule 0.435–0.510 long and 0.012–0.015 wide at mid-length, shaft representing its anterior half, with its distal tip moderately extended, provided with wide cuticular membrane forming large ventral process (Fig. 51 C). Right spicule 0.108–0.120 long, boat-shaped, sometimes with dorsal barb on distal tip (Fig. 51 D). Length ratio of right to left spicule 1:3.84 to 1:4.47. Tail conical, 0.354–0.411 long, its tip with sharp point (Fig. 51 B). Females: body 16.32–18.31 long, 0.245– 0.285 maximum width. Prostom 0.030–0.033, vestibule including prostom 0.177–0.210, muscular oesophagus 0.450–0.525 and glandular oesophagus 4.15–5.98 long. Deirids 0.105–0.123, nerve ring 0.264–0.309 and excretory pore 0.414–0.453 from anterior end. Tail conical, 0.273–0.303 long, its tip with sharp point (Fig. 51 E). Vulva post-equatorial, located 6.94 –8.30 from posterior end. Eggs elongate–oval, 0.036–0.039 x 0.021. Each pole of mature eggs (containing larvae) with one, less frequently two, narrow filaments up to 0.57 long (Fig. 51 F). Site: intestine Host: Catostomus macrocheilus Distribution: British Columbia Records: Anon. 1978; Arai & Mudry 1983, Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on pages 80-82, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530, {"references":["Yamaguti, S. (1935) Studies on the helminth fauna of Japan. Part 9. Nematodes of fishes, I. Japanese Journal of Zoology, 6, 337 - 386. http: // dx. doi. org / 10.1017 / s 0022149 x 00017788","Moravec, F., Margolis, L. & Boyce, N. P. (1981) Some nematodes of the genus Rhabdochona (Spirurida) from fishes of Japan. Vestnik Ceskoslovenske Spolecnosti Zoologicke, 45, 277 - 290.","Arai, H. P. & Mudry, D. R. (1983) Protozoan and metazoan parasites of fishes from the headwaters of the Parsnip and McGregor Rivers, British Columbia: a study of possible parasite transfaunations. Canadian Journal of Fisheries and Aquatic Sciences, 40, 1676 - 1684. http: // dx. doi. org / 10.1139 / f 83 - 194"]}

Rhabdochona ovifilamenta Weller, 1938 Synonyms: Rhabdochona laurentiana Lyster, 1940: Rhabdochona fortunatowi Dinnick, 1931 of Kussat (1969); Rhabdochona sp. of Arai & Kussat (1967) Description (after Moravec & Arai 1971). With characteristics of the genus. Males (three complete and three fragments): body 6.55–8.02 long, 0.095–0.136 maximum width. Pseudolabia rudimentary. Prostom relatively narrow, funnel-shaped, with indistinct basal teeth, lined internally with ribs forming forwardly projecting teeth (exact number not determined). Vestibule including prostom 0.111–0.138, muscular oesophagus 0.255–0.300, and glandular oesophagus 1.90–3.59 long. Relatively small bifurcate deirids 0.051–0.078, nerve ring 0.156–0.204, and excretory pore 0.237–0.264 from anterior end. Pairs of subventral precloacal papillae variable in number: the following combinations were observed—6+7, 7+9, 8+9 and 9+10. Another pair was located laterally at level of 4th subventral pair. Six pairs of post-cloacal papillae present, the 2nd pair lateral, the rest subventral (Fig. 49 A). Left spicule 0.390–0.420 long, slender, with lanceolate distal tip, and “slightly outlined” bifurcation with fine cuticular membrane (Fig. 49 B). Right spicule scoop-shaped, 0.105–0.117 long with reflected barb at tip. Length ratio of right to left spicule 1:3.52 to 1:3.78. Tail conical, 0.303–0.372 long, with distinct cuticular spike. Females (three complete and two fragments): body 11.75–21.76 long, 0.204–0.258 maximum width. Pseudolabia rudimentary. Prostom thick–walled with distinct basal teeth, 0.030–0.039 long, and 16 teeth projecting forwardly (Fig. 49 C). Vestibule including prostom 0.090–0.135, muscular oesophagus 0.276–0.558, and glandular oesophagus 1.60–4.42 long. Relatively large, “somewhat bifurcate“ deirids 0.039–0.060 (Fig. 49 D), nerve ring 0.126–0.210, and excretory pore 0.243 from anterior end. Vulva of younger females slightly pre-equatorial, in larger females distinctly post-equatorial, 6.23–8.98 from posterior end. Eggs oval, 0.036–0.042 x 0.018–0.021. Mature eggs embryonated. Entire surface covered with fine protuberances and numerous, short thread-like filaments (Fig. 49 E); filaments distributed uniformly over entire surface of most eggs but, in some, filaments appear restricted to area near poles. Tail conical, 0.294–0.315 long, with short cuticular spike. Comment: as already noted, Moravec & Arai (1971) suggested that R. ovifilamenta and R. milleri might be conspecific. Site: intestine Hosts: Catostomus catostomus (3, 4, 7); Catostomus commersonii (1, 8, 9, 11, 12); Catostomus platyrhynchus (4, 7, 8); Perca flavescens (5, 6, 10); Salvelinus fontinalis (2, 13) Distribution: Alberta, Ontario, Quebec Records: 1. Lyster 1940 (QC); 2. Choquette 1948a (QC); 3. Kussat 1966 (AB); 4. Arai & Kussat 1967 (AB); 5. Tedla & Fernando 1969a (ON); 6. Tedla 1969 (ON); 7. Kussat 1969 (AB); 8. Moravec & Arai 1971 (AB); 9. Dechtiar & Christie 1988 (ON); 10. Dechtiar & Lawrie 1988 (ON); 11. Dechtiar & Nepszy 1988 (ON); 12. Dechtiar et al. 1989 (ON); 13. Marcogliese & Cone 1991a (QC), Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on pages 77-79, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530, {"references":["Lyster, L. L. (1940) Parasites of freshwater fish. II. Parasitism of speckled and lake trout and the fish found associated with them in Lake Commandant, Quebec. Canadian Journal of Research, Section D, 18, 66 - 78. http: // dx. doi. org / 10.1139 / cjr 40 d- 005","Kussat, R. H. (1969) A comparison of aquatic communities in the Bow River above and below sources of domestic and industrial wastes from the city of Calgary. Canadian Fish Culturalist, 40, 3 - 31.","Arai, H. P. & Kussat, R. H. (1967) Observations on the distribution of parasites of certain catostomid fishes of the Bow River, Alberta. Canadian Journal of Zoology, 45, 1287 - 1290. http: // dx. doi. org / 10.1139 / z 67 - 140","Moravec, F. & Arai, H. P. (1971) The North and Central American species of Rhabdochona (Nematoda: Rhabdochonidae) of fishes, including Rhabdochona canadensis sp. nov. Journal of the Fisheries Research Board of Canada, 28, 1645 - 1662. http: // dx. doi. org / 10.1139 / f 71 - 245","Choquette, L. P. E. (1948 a) Parasites of freshwater fish. IV. Internal helminths parasitic in speckled trout (Salvelinus fontinalis (Mitchill )) in rivers and lakes of the Laurentide Park, Quebec, Canada. Canadian Journal of Research, Section D, 26, 204 - 211. http: // dx. doi. org / 10.1139 / cjr 48 d- 017","Kussat, R. H. (1966) Bottom fauna studies in relation to the biology of certain fishes of the Bow River. M. Sc. Thesis. Department of Biology, University of Calgary, Calgary, Alberta.","Tedla, S. & Fernando, C. H. (1969 a) Observations on the seasonal changes of the parasite fauna of yellow perch (Perca flavescens) from the Bay of Quinte, Lake Ontario. Journal of the Fisheries Research Board of Canada, 26, 833 - 843. http: // dx. doi. org / 10.1139 / f 69 - 081","Dechtiar, A. O. & Christie, W. J. (1988) Survey of the parasite fauna of Lake Ontario fishes, 1961 to 1971. In: Nepszy, S. J. (Ed.), Parasites of Fishes in the Canadian waters of the Great Lakes. Great Lakes Fishery Commission, Technical Report, No. 51, 66 - 95.","Dechtiar, A. O. & Lawrie, A. H. (1988) Survey of the parasite fauna of Lake Superior fishes, 1969 to 1975. In: Nepszy, S. J. (Ed.), Parasites of Fishes in the Canadian waters of the Great Lakes. Great Lakes Fishery Commission, Technical Report, No. 51, 1 - 18.","Dechtiar, A. O. & Nepszy, S. J. (1988) Survey of the parasite fauna of selected fish species from Lake Erie, 1970 ̶ 1975. In: Nepszy, S. J. (Ed.), Parasites of Fishes in the Canadian waters of the Great Lakes. Great Lakes Fishery Commission, Technical Report, No. 51, 49 - 65.","Dechtiar, A. O., MacLean, J. A. & Nepszy, S. J. (1989) Parasites of Fishes from Algonquin Park lakes. Ontario Fisheries, Technical Report. Series, No. 29, 10 pp.","Marcogliese, D. J. & Cone, D. K. (1991 a) Do brook charr (Salvelinus fontinalis) from insular Newfoundland have different parasites than their mainland counterparts? Canadian Journal of Zoology, 69, 809 - 811. http: // dx. doi. org / 10.1139 / z 91 - 119"]}

** Rhabdochona sp. Site: intestine Hosts: Ambloplites rupestris (1, 17); Ameiurus melas (6); Ameiurus nebulosus (2, 21); Catostomus catostomus (9, 11, 14, 23); Catostomus commersonii (2, 3, 9); Catostomus macrocheilus (11, 14); Coregonus clupeaformis (3); Cottus cognatus (11, 14); Couesius plumbeus (5, 7); Etheostoma caeruleum (17, 21); Etheostoma exile (19); Fundulus diaphanus (1); Lepomis gibbosus (2, 3); Lepomis macrochirus (1); Luxilus cornutus (16, 20, 21); Micropterus dolomieu (6); Morone chrysops (1); Mylocheilus caurinus (14, 15); Nocomis biguttatus (21); Notemigonus crysoleucas (17, 20); Notropis atherinoides (21); Notropis hudsonius (4); Oncorhynchus kisutch (6, 13, 15); Oncorhynchus mykiss (11, 13, 14); Oncorhynchus nerka (8); Oncorhynchus tshawytscha (13, 14, 15); Perca flavescens (2, 5, 7, 10); Percopsis omiscomaycus (18); Pimephales promelas (3); Prosopium williamsoni (11, 13, 14, 15, 22); Ptychocheilus oregonensis (11, 14, 15); Richardsonius balteatus (11, 14); Salvelinus fontinalis (6); Salvelinus fontinalis x Salvelinus namyacush (12); Salvelinus malma (11, 13, 14, 15); Semotilus atromaculatus (21) Distribution: Alberta, British Columbia, Labrador, Manitoba, Ontario Records: 1. Bangham & Hunter 1939 (ON); 2. Bangham 1941 (ON); 3. Bangham & Venard 1946 (ON); 4. Stewart- Hay 1951c (MB); 5. Bangham 1951 (ON); 6. Bangham & Adams 1954 (BC); 7. Bangham 1955 (ON); 8. Margolis 1957 (BC); 9. Threlfall & Hanek 1970a (LB); 10. Mudry & Anderson 1977 (AB); 11. Anon. 1978 (BC); 12. Dechtiar & Berst 1978 (ON); 13. Anon. 1981 (BC); 14. Arai & Mudry 1983 (BC); 15. Anon. 1984 (BC); 16. Byrne & Baker 1987 (ON); 17. Dechtiar & Christie 1988 (ON); 18. Dechtiar & Lawrie 1988 (ON); 19. Dechtiar et al. 1988 (ON); 20. Dechtiar et al. 1989 (ON); 21. Byrne 1992b (ON); 22. Nener et al. 1995 (BC); 23. Baldwin & Goater 2003 (AB), Published as part of Arai, Hisao P. & Smith, John W., 2016, Guide to the Parasites of Fishes of Canada Part V: Nematoda, pp. 1-274 in Zootaxa 4185 (1) on page 82, DOI: 10.11646/zootaxa.4185.1.1, http://zenodo.org/record/165530, {"references":["Bangham, R. V. & Hunter, G. W. III. (1939) Studies on fish parasites of Lake Erie. Distribution studies. Zoologica (New York), 24, 385 - 444.","Bangham, R. V. (1941) Parasites of fish of Algonquin Park lakes. Transactions of the American Fisheries Society, 70, 161 - 171. http: // dx. doi. org / 10.1577 / 1548 - 8659 (1940) 70 [161: pofoap] 2.0. co; 2","Bangham, R. V. & Venard, C. E. (1946) Parasites of fish of Algonquin Park lakes. II. Distribution studies. University of Toronto Studies in Biology Series, 53, 31 - 46. (Ontario Fisheries Research Laboratory Publication. No. 65.)","Stewart-Hay, R. K. (1951 c) A biological survey of Wellman Lake - Summer 1951. Manitoba Department of Mines and Natural Resources, Game and Fisheries Branch Report, 20 pp.","Bangham, R. V. (1951) Parasite records by location in 1951: Manitoulin Island and surrounding waters. University of Toronto, Ontario Fisheries Research Laboratory Report, 27 pp.","Bangham, R. V. & Adams, J. R. (1954) A survey of the parasites of freshwater fishes from the mainland of British Columbia. Journal of the Fisheries Research Board of Canada, 11, 673 - 708. http: // dx. doi. org / 10.1139 / f 54 - 043","Bangham, R. V. (1955) Studies on fish parasites of Lake Huron and Manitoulin Island. American Midland Naturalist, 53, 184 - 194. http: // dx. doi. org / 10.2307 / 2422308","Margolis, L. (1957) A study of the parasites of sockeye and pink salmon with particular reference to their application in distinguishing between Asiatic and North American stocks of these fishes on the high seas ̶ report of results of examination of 1956 samples. Fisheries Research Board of Canada Manuscript Report (Biology), No. 641, 24 pp.","Mudry, D. R. & Anderson, R. S. (1977) Helminth and arthropod parasites of freshwater fishes in Alberta, 1932 - 1975. Journal of Fish Biology, 11, 21 - 33. http: // dx. doi. org / 10.1111 / j. 1095 - 8649.1977. tb 04095. x","Dechtiar, A. O. & Berst, A. H. (1978) Parasite fauna of splake (Salvelinus fontinalis x S. namaycush). Proceedings of the Helminthological Society of Washington, 45, 249 - 254.","Arai, H. P. & Mudry, D. R. (1983) Protozoan and metazoan parasites of fishes from the headwaters of the Parsnip and McGregor Rivers, British Columbia: a study of possible parasite transfaunations. Canadian Journal of Fisheries and Aquatic Sciences, 40, 1676 - 1684. http: // dx. doi. org / 10.1139 / f 83 - 194","Anthony, D. D. (1984) Helminth parasites of white bass (Morone chrysops) from Lake Nipissing, Ontario. Program and Abstracts. 59 th Annual Meeting, American Society of Parasitologists, 05 - 09 August 1984. Snowbird, Utah, p. 27.","Byrne, P. J. & Baker, M. R. (1987) The biology of Rhabdochona cascadilla Wigdor, 1918 (Nematoda: Spirurida) in the common shiner from a southern Ontario stream. Program and Abstracts. 26 th Annual Meeting, Canadian Society of Zoologists, McGill University, 13 - 15 May 1987. Bulletin of the Canadian Society of Zoologists, 18, p. 22.","Dechtiar, A. O. & Christie, W. J. (1988) Survey of the parasite fauna of Lake Ontario fishes, 1961 to 1971. In: Nepszy, S. J. (Ed.), Parasites of Fishes in the Canadian waters of the Great Lakes. Great Lakes Fishery Commission, Technical Report, No. 51, 66 - 95.","Dechtiar, A. O. & Lawrie, A. H. (1988) Survey of the parasite fauna of Lake Superior fishes, 1969 to 1975. In: Nepszy, S. J. (Ed.), Parasites of Fishes in the Canadian waters of the Great Lakes. Great Lakes Fishery Commission, Technical Report, No. 51, 1 - 18.","Dechtiar, A. O., MacLean, J. A. & Nepszy, S. J. (1989) Parasites of Fishes from Algonquin Park lakes. Ontario Fisheries, Technical Report. Series, No. 29, 10 pp.","Byrne, P. J. (1992 b) On the biology of Rhabdochona rotundicaudatum and R. cascadilla (Nematoda: Thelazioidea) in stream fishes from southern Ontario, Canada. Canadian Journal of Zoology, 70, 485 - 493. http: // dx. doi. org / 10.1139 / z 92 - 073","Nener, J., Kieser, D., Thompson, J. A. J., Lockhart, W. L., Metner, D. A. & Roome, R. (1995) Monitoring of mountain whitefish Prosopium williamsoni from the Columbia River system near Castlegar, British Columbia: health parameters and contaminants in 1992. Canadian Technical Report of Fisheries and Aquatic Sciences, No. 2036: xi + 89 pp.","Baldwin, R. E. & Goater, C. P. (2003) Circulation of parasites among fishes from lakes in the Caribou Mountains, Alberta, Canada. Journal of Parasitology, 89, 215 - 225. http: // dx. doi. org / 10.1645 / 0022 - 3395 (2003) 089 [0215: copaff] 2.0. co; 2"]}

Key to species of Rhabdochona According to Moravec et al. (1981) the closest relative of R. zacconis Yamaguti, 1935 is probably R. canadensis Moravec & Arai, 1971; the two species “differ distinctly only in the position of the deirids (more anterior relative to length of the vestibule in R. canadensis) and the shape of the distal end and width of the left spicule”. There is possible confusion here because Moravec & Arai (1971) stated that the left spicule of R. canadensis is “conspicuously slender” but, at a width of 0.06–0.09 (see Moravec et al., 1981), it is not as slender as that of R. zacconis at 0.012–0.015. For these reasons the following key does not attempt to distinguish the two species (although separate descriptions are given). It is relevant to point out that neither Anon. (1978) nor Arai & Mudry (1983) described or illustrated the worms from Catostomus macrocheilus in British Columbia that they claimed represented R. zacconis. This species has not been previously reported from North America so it is possible that the worms represented R. canadensis rather than R. zacconis. 1 Mature eggs smooth, without filaments or gelatinous “formations”............................................. 2 - Mature eggs with gelatinous “formations”, mostly in the shape of polar caps, or filaments............................ 4 2 Left spicule longer than 0.8; length ratio of right to left spicule 1:10.2 to 1:11.9.......................... R. decaturensis - Left spicule shorter than 0.6; length ratio of right to left spicule 1:3.1 to 1:4.2..................................... 3 3 Right spicule with truncated proximal end; tail ends in rounded tip............................... R. rotundicaudatum - Right spicule with bulbous, convex proximal end; tail ends in sharp point............................... R. cascadilla 4 Prostom with 16 teeth; egg surfaces covered with fine protuberances and numerous short filaments.......... R. ovifilamenta - Prostom with 10 or 14 teeth............................................................................ 5 5 Prostom with 10 teeth................................................................................. 6 - Prostom with 14 teeth................................................................................. 7 6 Prostom lacks basal teeth; deirids small, bifurcate................................................. R. catostomi - Prostom with basal teeth; deirids medium-sized, bifurcate; eggs with gelatinous “formations” covering most of poles and lat- eral surfaces................................................................................. R. kisutchi 7 Tail tip rounded; eggs with two long single, rarely double, filaments; parasitic in Cottidae....................... R. cotti - Tail ends in sharp point............................................................................... 8 8 Both egg poles with numerous fine filaments........................................................ R. milleri - Both egg poles with at least one filament, sometimes two filaments on one or both poles......... R. canadensis / R. zacconis

Keys are provided for the identification of the nematode species known to be parasites of Canadian fishes. The nematodes are described and illustrated, with a note of the site(s) they occupy in named fish host(s) and their geographical distribution. Parasite records are given by author and date, full details of which can be found in a bibliography of over 800 references. Diagnoses and keys for 22 Families, 47 genera and 88 species of nematodes are also given, together with a glossary of terms, a host-parasite list, and indices to both nematode parasites and hosts.

The eyeworm Thelazia callipaeda has been reported in different European countries, i.e. Italy, France, Germany, Switzerland, Spain, Portugal, Bosnia and Herzegovina, Croatia and Romania. The present article describes the first autochthonous case of ocular thelaziosis in a dog from Greece, thus revealing a new spot of infection in Europe. The dog in this case report, most likely infected at the northern borders of Greece, was referred to a private veterinary practice with conjunctivitis, oedema, keratitis, epiphora and mucoid discharge in both eyes. Seventy-seven nematodes were removed from both eyes, and the dog was treated with two subcutaneous injections of ivermectin 14 days apart, in combination with a topical antimicrobial medication. The parasites were morphologically and molecularly identified as T. callipaeda. Although in Greece there is no information about the presence and distribution of the fruit fly Phortica variegata, i.e. the intermediate host of T. callipaeda, the location where the dog was infected is environmentally suitable for its development. The present report of this zoonotic parasitosis indicates that in Greece, along with endemic areas in Spain and Italy, T. callipaeda is currently reaching its southernmost distribution limit in Europe.

Scanning electron microscopy (SEM) was used to study the surface ultrastructure of femaleThelazia lacrymalisobtained from naturally infected cattle. At the anterior end, the buccal capsule was cup shaped. The mouth was without lips and was surrounded by four cephalic papillae and two amphids. There were two lateral cervical papillae. Also, a single small papilla was seen on the ventral side, close to the vulvar opening. The vulva was located posterior to the end of the oesophagus and the tail carried an anal pore and a pair of phasmids near the tip. The cuticle was transversally annulated with fine striations.

Background Thelazia callipaeda (Spirurida, Thelaziidae), also known as “oriental eyeworm”, is a small nematode parasite that lives in the conjunctival sac of domestic and wild carnivores, rabbits and even humans, causing mild (e.g., conjunctivitis, epiphora, and ocular discharge) to severe (e.g., keratitis, and corneal ulcers) ocular disease. This study reports, for the first time, the occurrence of T. callipaeda infection in the Balkan regions (i.e., Bosnia and Herzegovina and Croatia), it provides genetic evidence on the origin of the infection in that area and discusses potential expansion pathways in the near future. Methods This survey was conducted in two Western Balkan countries, Bosnia and Herzegovina and Croatia. At necropsy, from January 2011 to April 2014, a total of 184 carcasses of red foxes were examined throughout the study area and worms were collected from the conjunctival sac. In the same period, worms were also collected during clinical examination from the conjunctival sac of four dogs and a cat from Bosnia and Herzegovina and two dogs from Croatia. All nematodes collected were morphologically identified and molecularly characterized by sequencing of partial cox1 gene. Results T. callipaeda was observed in 51 (27.71%) foxes and the highest prevalence (50.0%) was in the region of East Bosnia. Beside the 4 cases of hyperemia (7.84%), most of the infected animals had no signs of ocular infection (n = 47, 92.15%). A total of 417 adult nematodes collected (364 from foxes, 51 from dogs, 2 from cat) were morphologically and molecularly identified as T. callipaeda haplotype 1. Conclusion This is the first report of autochthonous cases of T. callipaeda infection in red foxes, dogs and cat in Bosnia and Herzegovina and Croatia and data presented here suggest that reports of thelaziosis in other Balkan areas are, as yet, not diagnosed most likely due to the lack of awareness of practitioners. In addition, data regarding the spread of the infection in Europe over the last ten years suggests that an increasing pattern in the distribution of this disease in domestic and wild animals should be expected in the future.

To the EditorIn their recently published manuscript, Kim and colleagues[1] describe a case of human intraocular infestation byworms. The authors erroneously identify the nematodecollected in the conjunctiva as Thelazia callipaeda (Spiru-rida: Thelaziidae). However, the morphological identifica-tion of T. callipaeda adult nematodes relies on evidence ofthe presence of a buccal capsule with the internal marginseverted and subdivided by excavations into six festoons andthe mouth opening with a hexagonal profile. These mor-phological features clearly differ from those of the nema-tode in the figure presented by Kim and colleagues [1]. Theauthors also state that the life cycle of T. callipaeda remainsunclear and discuss the possibility of human infectionthrough the skin or by drinking untreated water. It isimportant for physicians and ophthalmologists who may notbe experts in parasitology to realize that, similarly to othermembers of the Thelaziidae, and at a higher taxonomicallevel of the order Spirurida, T. callipaeda is transmittedonly by secretophagous flies [2]. T. callipaeda develops thefirst to third infective stages of larvae within its body andthese are then deposited into the eyes of receptive hostswhen flies feed on lachrymal secretions.The lack of knowledge of this helminth’s infestation isprobably due to the fact that, until the last decade, the bodyof literature on this nematode was published in languagesother than English (mainly Chinese) and thus it was notaccessible to a great part of the western scientific commu-nity. This nematode was commonly known as the ‘‘orientaleye-worm’’ because of its distribution in Asian countrieswhere it is still frequently reported as being responsible forthelaziosis in humans, carnivores (dogs, cats and foxes) andrabbits, causing mild to severe clinical signs (includingepiphora, conjunctivitis, keratitis and/or even cornealulcers) [2]. The little attention medical researchers tend topay human thelaziosis may also be attributable to the dif-ficulties in its clinical diagnosis and differentiation fromallergic conjunctivitis, particularly when small numbers ofadult or larval stages are present in affected patients. Overthe last decades, however, infestation by T. callipaeda hasgained the interest of the scientific community and there isevidence of its spreading throughout Europe, with a highprevalence (up to 60%) in dogs being recorded in someareas of southern Italy [2]. In the same areas the frequencyof wolves, beech martens, brown hares and wild cats asdefinitive hosts for T. callipaeda has been recently dem-onstrated. In addition, there is evidence for its occurrence indogs in France, Germany and Switzerland. Recently, thefirst four cases of human thelaziosis in Europe have alsobeen diagnosed [3]. Correct knowledge of the biology ofT. callipaeda is, therefore, pivotal in addressing the pre-vention of human thelaziosis (e.g., use of nets to protectchildren while sleeping, keeping their faces and eyes clean).Domenico OtrantoDepartment of Veterinary Public Healthand Animal SciencesFaculty of Veterinary Medicine of BariStrada Provinciale per Casamassima km 370010 Valenzano (Bari), ItalyReferences

Oxyspirura sp. Momotus momota marcgraviana Pinto & Camargo, eyes, Mato Grosso do Sul (Vicente et al. 1995).

Using available records, unpublished information retrieved from the Helminthological Collection of the Oswaldo Cruz Institute (CHIOC) and published reports, a checklist of the recorded helminth parasites of endangered vertebrates from Brazil was generated. A total of 772 records and 186 helminth species (6 Acanthocephala, 83 Nematoda, 23 Cestoda, 64 Trematoda, 10 Monogenea) in 76 host species (7 Actinopterygii, 8 Chondrichthyes, 1 Amphibia, 10 Reptilia, 22 Aves, 28 Mammalia) from Brazil were listed in the present work, including 39 undetermined helminth species and 10 new host records. This is the first compilation of the helminth parasites of threatened vertebrates in Brazil and in the Neotropics.

Oxyspirura sp. Momotus momota marcgraviana Pinto & Camargo, eyes, Mato Grosso do Sul (Vicente et al. 1995)., Published as part of Muniz-Pereira, Luís C., Vieira, Fabiano M. & Luque, José L., 2009, Checklist of helminth parasites of threatened vertebrate species from Brazil, pp. 1-45 in Zootaxa 2123 on page 13, DOI: 10.5281/zenodo.188170, {"references":["Vicente, J. J., Rodrigues, H. O., Gomes, D. C. & Pinto, R. M. (1995) Nematoides do Brasil. Parte IV. Nematoides de aves. Revista Brasileira de Zoologia, 12, 1 - 273."]}

Thelazia sp. Crax blumenbachii Spix, eyes, Mato Grosso do Sul (Vicente et al. 1995) (CHIOC 11340)., Published as part of Muniz-Pereira, Luís C., Vieira, Fabiano M. & Luque, José L., 2009, Checklist of helminth parasites of threatened vertebrate species from Brazil, pp. 1-45 in Zootaxa 2123 on page 13, DOI: 10.5281/zenodo.188170, {"references":["Vicente, J. J., Rodrigues, H. O., Gomes, D. C. & Pinto, R. M. (1995) Nematoides do Brasil. Parte IV. Nematoides de aves. Revista Brasileira de Zoologia, 12, 1 - 273."]}

Thelazia chungkingensis Hsü Mitu mitu (Linnaeus), eyes, Central Brazil (Strachan 1957; Vicente et al. 1995)., Published as part of Muniz-Pereira, Luís C., Vieira, Fabiano M. & Luque, José L., 2009, Checklist of helminth parasites of threatened vertebrate species from Brazil, pp. 1-45 in Zootaxa 2123 on page 13, DOI: 10.5281/zenodo.188170, {"references":["Strachan, A. A. (1957) Eye worms of the family Thelaziidae from Brazilian birds. Canadian Journal of Zoology, 35, 179 - 187.","Vicente, J. J., Rodrigues, H. O., Gomes, D. C. & Pinto, R. M. (1995) Nematoides do Brasil. Parte IV. Nematoides de aves. Revista Brasileira de Zoologia, 12, 1 - 273."]}

Oxyspirura matogrosensis Rodrigues Momotus momota marcgraviana Pinto & Camargo, eyes, Mato Grosso do Sul (Vicente et al. 1995)., Published as part of Muniz-Pereira, Luís C., Vieira, Fabiano M. & Luque, José L., 2009, Checklist of helminth parasites of threatened vertebrate species from Brazil, pp. 1-45 in Zootaxa 2123 on page 13, DOI: 10.5281/zenodo.188170, {"references":["Vicente, J. J., Rodrigues, H. O., Gomes, D. C. & Pinto, R. M. (1995) Nematoides do Brasil. Parte IV. Nematoides de aves. Revista Brasileira de Zoologia, 12, 1 - 273."]}

Thelazia anadorhynchi Strachan Anodorhynchus hyacinthinus (Latham), eyes, central Brazil (Strachan 1957)., Published as part of Muniz-Pereira, Luís C., Vieira, Fabiano M. & Luque, José L., 2009, Checklist of helminth parasites of threatened vertebrate species from Brazil, pp. 1-45 in Zootaxa 2123 on page 13, DOI: 10.5281/zenodo.188170, {"references":["Strachan, A. A. (1957) Eye worms of the family Thelaziidae from Brazilian birds. Canadian Journal of Zoology, 35, 179 - 187."]}

Thelazia anolabiata (Molin) Anodorhynchus hyacinthinus (Latham), eyes, Central Brazil (Vicente et al. 1995). Crax fasciolata pinima (Pelzeln), eyes, Mato Grosso do Sul (Vicente, et al. 1995) (CHIOC 14473, 14556, 15535, 15598, 30499 a̅b)., Published as part of Muniz-Pereira, Luís C., Vieira, Fabiano M. & Luque, José L., 2009, Checklist of helminth parasites of threatened vertebrate species from Brazil, pp. 1-45 in Zootaxa 2123 on page 13, DOI: 10.5281/zenodo.188170, {"references":["Vicente, J. J., Rodrigues, H. O., Gomes, D. C. & Pinto, R. M. (1995) Nematoides do Brasil. Parte IV. Nematoides de aves. Revista Brasileira de Zoologia, 12, 1 - 273."]}

Thelazia sp. Crax blumenbachii Spix, eyes, Mato Grosso do Sul (Vicente et al. 1995) (CHIOC 11340).

Oxyspirura cephaloptera (Molin) Momotus momota marcgraviana Pinto & Camargo, eyes, Mato Grosso (Vicente et al. 1995)., Published as part of Muniz-Pereira, Luís C., Vieira, Fabiano M. & Luque, José L., 2009, Checklist of helminth parasites of threatened vertebrate species from Brazil, pp. 1-45 in Zootaxa 2123 on page 13, DOI: 10.5281/zenodo.188170, {"references":["Vicente, J. J., Rodrigues, H. O., Gomes, D. C. & Pinto, R. M. (1995) Nematoides do Brasil. Parte IV. Nematoides de aves. Revista Brasileira de Zoologia, 12, 1 - 273."]}

Two trials were conducted to evaluate the therapeutic and prophylactic activity of milbemycin oxime (Interceptor, Novartis Animal Health) against the eye-worm Thelazia callipaeda (Spirurida, Thelaziidae) infection. In Trial 1, the therapeutic efficacy of milbemycin oxime was evaluated in 55 naturally infected dogs treated with min. 0.5mg/kg milbemycin oxime. The dogs were clinically examined for the presence of eyeworms before and again 7 days after treatment. Dogs still positive were given a second treatment and re-checked again a week later. Forty-eight of the 55 dogs tested negative 1 week after treatment (87.3% reduction of infection rate). Following the second treatment 6 of these 7 dogs tested negative 1 week later resulting, after two treatments, in a reduction of infection rate of 98.2%. In Trial 2, the prophylactic efficacy of milbemycin oxime was evaluated in 60 uninfected dogs. Thirty dogs were treated with milbemycin oxime monthly from June to November with the recommended dose rate for the prevention of heartworm disease (> or =0.5mg/kg), 30 dogs served as untreated controls. At the end of the trail 1 dog in the treated group and 10 dogs in the control group became infected during the trial. The incidence of infection differed significantly between treated and control dogs (p=0.0056). The efficacy of the prophylactic use of a monthly treatment with milbemycin oxime showed 90% efficacy in reducing T. callipaeda infection rate.

Three male specimens of the eyeworm, Oxyspirura chabaudi, were found during the post mortem examination of one individual of Turdus merula L. (Passeriformes). This is the first record of Turdus merula as a host for O. chabaudi.

Rhabdochona canadensis Moravec & Arai, 1971 Intestine. ESTADO DE M��XICO: San Jer��nimo (Ixtapan de la Sal): Hybopsis boucardi (134). GUERRERO: Petatl��n: H. boucardi (134). HIDALGO: Tenango: Dionda ipni (136). MICHOAC��N: San Juanico: H. boucardi (134). MORELOS: Amacuzac (Las Planchas): H. boucardi (134); Chalma (El Platanar): H. boucardi (17). OAXACA: Cuyotepeji, Huajuapan de Le��n, Michapa, Petlalcingo: H. boucardi (134). QUER��TARO: Las Zu��igas: Aztecula sallaei (136)., Published as part of Garrido-Olvera, Lorena, Garc��a-Prieto, Luis & Le��n, Gerardo P��rez-Ponce De, 2006, Checklist of the adult nematode parasites of fishes in freshwater localities from Mexico, pp. 1-45 in Zootaxa 1201 on page 28, DOI: 10.5281/zenodo.273411, {"references":["134. Salgado-Maldonado, G., Cabanas-Carranza, G., Caspeta-Mandujano, J. M., Soto-Galera, E., Mayen-Pena, E., Brailovsky, D. & Baez-Vale, R. (2001) Helminth parasites of freshwater fishes of the Balsas River drainage basin of Southwestern Mexico. Comparative Parasitology, 68, 196 - 203.","136. Salgado-Maldonado, G., Cabanas-Carranza, G., Soto-Galera, E., Pineda-Lopez, R., Caspeta- Mandujano, J. M., Aguilar-Castellanos, E. & Mercado-Silva, N. (2004) Helminth parasites of freshwater fishes of the Panuco River Basin, East Central Mexico. Comparative Parasitology, 71, 190 - 202.","17. Caspeta-Mandujano, J. M. & Mejia-Mojica, H. (2004) Seasonal dynamics of the occurrence and maturation of Rhabdochona canadensis in its definitive host, Notropis boucardi, of the Chalma River, State of Morelos, Mexico. Helminthologia, 41, 121 - 123."]}

Rhabdochona sp. Intestine. MORELOS: Amacuzac (Las Planchas), Chalma (La Angostura): Hybopsis boucardi (37); Yautepec: Archocentrus nigrofasciatus (120). NUEVO LE��N: Salinillas (An��huac): Aplodinotus grunniens, Oreochromis aureus (32). PUEBLA: Alchichica: Poblana alchichica (36); La Preciosa: Poblana letholepis (36). TABASCO: Carrizal: Ictalurus furcatus (CNHE 5257); El Rosario: A. grunniens, Guavina guavina, I. furcatus, Megalops atlanticus, Strongylura sp.(40); San Pedro (Balanc��n): I. furcatus (126); Usumacinta (Boca del Cerro): I. furcatus (29). TAMAULIPAS: Falc��n (Benavides): I. furcatus (63). VERACRUZ: Pantepec: Ictalurus punctatus (116)., Published as part of Garrido-Olvera, Lorena, Garc��a-Prieto, Luis & Le��n, Gerardo P��rez-Ponce De, 2006, Checklist of the adult nematode parasites of fishes in freshwater localities from Mexico, pp. 1-45 in Zootaxa 1201 on page 27, DOI: 10.5281/zenodo.273411, {"references":["37. Flores-Sotelo, M. T. (1998) Comparacion de los helmintos parasitos de Hybopsis boucardi (Gunther, 1968) (Pisces: Cyprinidae) en dos localidades del Municipio de Coatlan del Rio en el estado de Morelos, Mexico. B. S. Thesis, Facultad de Ciencias Biologicas, Universidad Autonoma del Estado de Morelos, Cuernavaca, Morelos, Mexico, 45 pp.","32. Escobar-Gonzalez, B. (1997) Parasitos del besugo (Aplodinotus grunniens) Rafinesque, 1819 y de la tilapia (Sarotherodon aurea) Steindachner, 1864 en la Laguna de Salinillas, Anahuac, Nuevo Leon, Mexico. B. S. Thesis, Facultad de Ciencias Biologicas, Universidad Autonoma de Nuevo Leon, Monterrey, Nuevo Leon, Mexico, 54 pp.","36. Flores-Negrete, E. (1998) Estudio poblacional de tres especies de Poblana (Pisces: Atherinopsidae) en tres lagos crater de Puebla, Mexico. M. S. Thesis, Facultad de Ciencias, Universidad Nacional Autonoma de Mexico, Mexico City, 101 pp.","40. Fucugauchi-Suarez del Real, M. G., Garcia-Magana, L. & Brito-Arjona, B. del R. (1988) Analisis previo de la parasitofauna de peces de la Laguna del Rosario, Huimanguillo, Tabasco. Divulgacion Cientifica, 1, 319 - 335.","126. Pineda-Lopez, R., Carballo-Cruz, V., Fucugauchi-Suarez del Real, M. G. & Garcia-Magana, L. (1985) Metazoarios parasitos de peces de importancia comercial de la Region de los Rios, Tabasco, Mexico. Usumacinta, 1, 197 - 270.","29. Del Rio-Rodriguez, E. (1994) Estudio prospectivo de la infracomunidad de parasitos que infectan al \" bobo \" Ictalurus meridionalis (Gunther, 1864) en Boca del Cerro, Tenosique, Tabasco, como antecedente al proyecto de embalsamiento de esta area. B. S. Thesis, Division Academica de Ciencias Biologicas, Universidad Juarez Autonoma de Tabasco, Villahermosa, Tabasco, Mexico, 112 pp.","63. Mancias-Hinojosa, B. (1984) Helmintos parasitos de Ictalurus furcatus en la Presa Falcon, Nueva Ciudad Guerrero, Tamaulipas, Mexico. B. S. Thesis, Facultad de Ciencias Biologicas, Universidad Autonoma de Nuevo Leon, Monterrey, Nuevo Leon, Mexico, 58 pp."]}

Rhabdochona guerreroensis Caspeta��Mandujano, Aguilar��Aguilar & Salgado�� Maldonado, 2002 (E) Intestine. GUERRERO: La Hamaca (Coyuca de Ben��tez): Sicydium multipunctatum (15). JALISCO: Manantl��n: S. multipunctatum (15, 138)., Published as part of Garrido-Olvera, Lorena, Garc��a-Prieto, Luis & Le��n, Gerardo P��rez-Ponce De, 2006, Checklist of the adult nematode parasites of fishes in freshwater localities from Mexico, pp. 1-45 in Zootaxa 1201 on page 28, DOI: 10.5281/zenodo.273411, {"references":["15. Caspeta-Mandujano, J. M., Aguilar-Aguilar, R. & Salgado-Maldonado, G. (2002) Rhabdochona guerreroensis n. sp. (Nematoda: Rhabdochonidae) from the intestine of the gobiid Sicydium multipunctatum from fresh waters in Mexico. Journal of Parasitology, 88, 746 - 749.","138. Salgado-Maldonado, G., Mercado-Silva, N., Cabanas-Carranza, G., Caspeta-Mandujano, J. M., Aguilar-Aguilar, R. & Iniguez-Davalos, L. I. (2004) Helminth parasites of freshwater fishes of the Ayuquila River, Sierra de Manantlan Biosphere Reserve, West Central Mexico. Comparative Parasitology, 71, 67 - 72."]}