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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

portuguesEspecimes de Rhabdochona (Rhabdochona) acuminata (Molin, 1860) foram coletados em Astyanax aff. fasciatus (Cuvier, 1819) do Lago Guaiba, municipios de Guaiba (30°08.28'S, 51°18.53'W) e, Barra do Ribeiro (30°17.11'S, 51°18.01'W), no sul do Brasil. No presente estudo, a prevalencia de R. (R.) acuminata foi baixa (1,43%) quando comparada com outros estudos realizados com especies de Astyanax no Brasil. Os especimes de R. (R.) acuminata apresentaram algumas diferencas morfologicas (principalmente nos deirideos) que nao haviam ainda sido registradas para esta especie. Este e o primeiro registro de R. (R.) acuminata para o Lago Guaiba, contribuindo para o conhecimento da distribuicao deste nematoide na America do Sul. EnglishSpecimens of Rhabdochona (Rhabdochona) acuminata (Molin, 1860) were collected in Astyanax aff. fasciatus (Cuvier, 1819) from Lake Guaiba, municipalities of Guaiba (30°08.28'S, 51°18.53'W) and Barra do Ribeiro (30°17.11'S, 51°18.01'W), southern Brazil. In the present study, the prevalence of R. (R.) acuminata was low (1.43%) when compared to other studies performed with Astyanax spp. from Brazil. The specimens of R. (R.) acuminata showed some morphological differences (mainly the deirids) that have not yet been reported for the species. This is the first report of R. (R.) acuminata from Lake Guaiba, filling a gap of occurrence of this nematode in South America.

Moravec, František, Nagasawa, and Kazuya (2018): Rhabdochona angusticaudata sp. n. (Nematoda: Rhabdochonidae) from the Japanese eel Anguilla japonica, and new records of some other nematodes from inland fishes in Japan. Folia Parasitologica (016) 65: 1-22, DOI: 10.14411/fp.2018.016, URL: http://dx.doi.org/10.14411/fp.2018.016

Rhabdochona angusticaudata sp. n. Figs. 8–10 ZooBank number for species: urn:lsid:zoobank.org:act: 32A17EE6-4EFE-4416-BF90-A34F066B94CE Description. Medium-sized nematodes with finely transversely striated cuticle Fig. 10A,B,F). Lateral alae absent. Mouth roughly hexagonal. Four small submedian cephalic papillae, 2 lateral amphids and 4 submedian sublabia present (Figs. 8E, 9A–E). Prostom funnel-shaped, without basal teeth (Fig. 8B,D); anterior teeth 14–16 in number, 3–4 dorsal, 3–4 ventral and 4 lateral (arranged in 2 pairs) on either side (Figs. 8B–E, 9A–E, 10A). Deirids small, non-bifurcated, with rounded ends, situated slightly asymmetrically approximately at mid-length of vestibule (Figs. 8A–C,F, 9F, 10B). Excretory pore at level of posterior part of muscular oesophagus (Figs. 8A,C, 10A). Tail of both sexes conical, slender, with sharply pointed tip. Male (2 complete and 1 incomplete specimens; holotype; measurements of paratypes in parentheses): Length of body 8.42 mm (13.6 mm in complete specimen), maximum width 78 (81). Prostom 21 (18–21) long and 15 (15) wide in lateral view. Length of vestibule including prostom 126 (117–126). Muscular oesophagus 231 (204–228) long, 24 (24–27) wide, length of glandular oesophagus 1.18 (1.35–1.40) mm, width 45 (48–60). Nerve ring, excretory pore and deirids 207 (177–207), 297 (270–312) and 80 (63–66), respectively, from anterior extremity. Preanal papillae: 9 subventral and 1 lateral pairs present; lateral pair situated at level of third subventral pair (counting from cloacal opening). Of 6 postanal pairs of papillae, second pair situated more laterally, remaining pairs subventral; lateral pair just posterior to first subventral pair (Figs. 8L, 10C). Minute phasmids situated laterally short distance posterior to level of last pair of postanal papillae (Figs. 8L, 10D). Precloacal ventral cuticular ornamentations (area rugosa) absent. Large (left) spicule well sclerotised, 384 (300) long; length of its shaft 183 (144), representing 48% (48%) of whole spicule length; distal tip moderately widened, lanceolate (Fig. 8G,H,L). Small (right) spicule boat-shaped, 87 (81) long, with distinct dorsal barb at distal tip (Fig. 8K, L). Length ratio of spicules 1: 4.4 (1: 3.7). Length of tail 300 (255). Female (1 gravid specimen with mature eggs, allotype): Length of body 19.1 mm, maximum width 165. Prostom 24 long and 18 wide. Length of vestibule including prostom 123. Muscular oesophagus 306 long, 27 wide, length of glandular oesophagus 1.63 mm, width 63. Nerve ring, excretory pore and deirids 219, 300 and 90, respectively, from anterior extremity. Vulva equatorial, 9.63 mm from anterior extremity (at 50% of body length) (Fig. 10F); vagina muscular, 66 long, directed posteriorly from vulva. Uterus filled with many eggs. Fully developed eggs larvated, oval, thick-walled, size 39–42 × 21–24, with smooth surface, without filaments; thickness of egg wall 4 (Fig. 8I). Tail conical, slender, 333 long, ending in sharp cuticular spike (Figs. 8J,M, 10E). Type host: Japanese eel, Anguilla japonica (Anguillidae, Anguilliformes). Site of infection: Intestine. Type locality: Renjoji River (brackish-water area and freshwater middle-reaches), Ainan, Ehime Prefecture, Shikoku, Japan (collected 16 and 25 June 2007). Total prevalence and intensity: 19% (3 fish infected/16 fish examined); 9 nematodes. Brackish-water area near the river mouth: 2 fish infected, 46.5 and 49.4 cm TL/5 fish examined, 32.0– 49.4 cm TL; 1 and 4 nematodes. Freshwater middle-reaches of the river: 9% (1 fish infected, 47.5 cm TL/11 fish examined, 35.2–53.2 cm TL); 4 nematodes. Deposition of type specimens: IPCAS N-1157 (mounted on SEM stubs). Etymology: The specific name angusticaudata (= narrow-tailed) is the Latin adjective, relating to the characteristic feature of this species, i.e., a markedly narrow female tail. Remarks. At present the genus Rhabdochona Railliet, 1916 comprises about 100 species parasitising freshwater fishes in all zoogeographical regions (Moravec 2010). The general morphology of R. angusticaudata sp. n., especially the number of prostomal teeth and no ornamentations at the tip of the tail, indicates that this species belongs to the nominotypic subgenus Rhabdochona, as defined by Moravec (1975). Most species of this subgenus possess bifurcate deirids and only a few of them, e.g. Rhabdochona acuminata (Molin, 1860), Rhabdochona marcusenii Moravec et Jirkû, 2014 or Rhabdochona fabianae Ramallo, 2005, have simple, rod-like deirids (Cremonte et al. 2002, Moravec and Jirkû 2014, Ramallo 2005) or the deirids are hammer-shaped (Rhabdochona papuanensis Moravec, ŘÍha et Kuchta, 2008) or oval, leaf-like (Rhabdochona pseudomysti Moravec et Yooyen, 2011) (see Moravec et al. 2008, Moravec and Yooyen 2011). However, the study of the exact shape of deirids in Rhabdochona usually requires SEM examination, but this method has not yet been used for many species. The non-bifurcated deirids with rounded distal tips, the character of anterior prostomal teeth, absence of basal teeth, a slender female tail and non-filamented eggs of R. angusticaudata sp. n. are also found in two species of Rhabdochona that are specific parasites of freshwater eels: Rhabdochona anguillae Spaul, 1927 infecting A. anguilla in Europe and Rhabdochona keralaensis Moravec, Sheeba et Kumar, 2012 in Anguilla bengalensis (Gray) in India (Spaul 1927, Moravec et al. 2012b). Of these, R. keralaensis markedly differs from the new species in the size of body (body length of male and female 12.5–17.1 and 22.3–27.8 mm, respectively, vs 8.4–13.6 mm and 19.1 mm), length of the left spicule (585–636 µm vs 300–384 µm), more numerous pairs of subventral preanal papillae (11–13 vs 9), presence (vs absence) of the bifurcated cuticular membrane forming a distinct dorsal outgrowth on the distal tip of the left spicule and a somewhat different arrangement of anterior prostomal teeth. Rhabdochona anguillae, as redescribed by Moravec (1975) and Saraiva and Moravec (1998), differs from the new species mainly in the lengths of spicules (left and right spicule 460–660 and 130–150 µm long, respectively, vs 300–384 and 81–87µm), in the relative length of shaft of the left spicule representing 56–60% (vs 48%) of the total spicule length, the dorsal barb on the right spicule is indistinct (vs right spicule with a conspicuous dorsal barb) and its fully developed eggs are larger (41–54 × 25–30 µm vs 39–42 ×21–24 µm). An inadequately described species, Rhabdochona minjiangensis Wang, 1976, was reported from Anguilla japonica in China (see PRLFTU 1976, Peng et al. 2011). Although it parasitises the same host species as R. angusticaudata sp. n., it can be easily distinguished from it by the length of the left spicule (640–700 µm vs 300–384 µm), the absence (vs presence) of a dorsal barb on the right spicule and by more numerous (11 vs 9) pairs of subventral preanal papillae. In these features, R. minjiangensis is more similar to R. anguillae and R. keralaensis. Unfortunately, some taxonomically important morphological features, such as the shape of deirids or the detailed structure of the left spicule, were not provided in the description of R. minjiangensis. Moreover, the number of reported anterior prostomal teeth (4 pairs) is probably misleading, because these were not studied in apical view, and lateral preanal and postanal papillae were apparently overlooked. Therefore, a redescription of this species based on LM and SEM examinations is needed. To date, six valid species of Rhabdochona have been reported from fishes in Japan: Rhabdochona coronacauda Belous, 1965, Rhabdochona denudata honshuensis Moravec et Nagasawa, 1989, Rhabdochona japonica Moravec, 1975, Rhabdochona oncorhynchi (Fujita, 1921), Rhabdochona tridentigeris Yamaguti, 1941 and Rhabdochona zacconis Yamaguti, 1935 (see Nagasawa 2017). Consequently, R. angusticaudata sp. n. is the seventh species of this genus known to occur in Japan. By the general morphology including the length of the left spicule, the new species resembles R. denudata honshuensis, a parasite of cyprinids, but these species can be easily distinguished from each other by the shape of deirids, which are simple in R. angusticaudata sp. n. and bifurcate in R. denudata honshuensis. In this study, several individuals of A. japonica from the brackish-water area near the mouth of the Renjoji River were found to be infected by R. angusticaudata sp. n. (see “Total prevalence and intensity”), which, however, does not indicate that the nematode is a brackish-water parasite. Like other members of the genus, R. angusticaudata sp. n. is a freshwater parasite and considered to infect A. japonica in the freshwater environment (e.g. middle-reaches of rivers). Some infected eels may have moved downstream to the brackish-water region.

Rhabdochona zacconis Yamaguti, 1935 Fig. 11 Syn.: Rhabdochona marinum Roytman, 1963. Host: Big-scaled redfin, Tribolodon hakonensis (Cyprinidae, Cypriniformes). Site of infection: Intestine. Locality: Takahara River (a tributary of the Jinzu River), Hida, Gifu Prefecture, Honshu, Japan (collected 1 June 2009). Prevalence and intensity: 13% (3 fish infected, 16.0– 19.4 cm TL/23 fish examined, 14.0– 21.8 cm TL); 1–5 (mean 2) nematodes per fish. Deposition of voucher specimens: IPCAS N-38. Remarks. The morphology of the present specimens is in full agreement with the redescription of R. zacconis provided by Moravec (1975) and Moravec et al. (1981), based on LM examination of specimens from the same host species (T. hakonensis) in Japan. Therefore, we refrain from describing these nematodes. However, the SEM study, used for the first time in this species, made it possible to confirm some features (e.g. cephalic papillae, amphids, arrangement of anterior prostomal teeth, presence of sublabia, shape of deirids, distribution of genital papillae) that are not easily visible using LM (Fig. 11). Rhabdochona zacconis is known to be distributed in Japan, eastern Russia and western Canada, parasitising cypriniform fishes of the genera Catostomus Lesueur (Catostomidae), Tribolodon Sauvage and Zacco Jordan et Evermann (both Cyprinidae) (Moravec 1975, Moravec et al. 1981, Arai and Mudry 1983, Arai and Smith 2016). In Japan, this parasite was previously recorded by Yamaguti (1935) from Zacco platypus (Temminck et Schlegel) in Nagano Prefecture, Honshu, by Moravec et al. (1981) from T. hakonensis and Z. platypus in Hokkaido (Lakes Akan and Shikotsu [reported erroneously as Chitose, see Nagasawa 2017] and Chihase River) and Honshu (Lake Biwa) (see also Moravec 1975), by Moravec and Nagasawa (1989) from T. hakonensis from several localities in Hokkaido and Honshu, and by Moravec et al. (1998) from T. hakonensis in the Okitsu River, Shizuoka Prefecture, Honshu, where they studied the seasonal maturation cycle of R. zacconis in this host. This parasite was recorded from eastern Russia (Sea of Japan, Putiyatin Island) and reported by Russian authors as Rhabdochona denudata (Dujardin, 1845) or as R. marinum from Tribolodon brandtii (Dybowski) (see Moravec 1975). Rhabdochona zacconis was also reported from Catostomus macrocheilus Girard in British Columbia, western Canada (Arai and Mudry 1983, Arai and Smith 2016).

Collections of parasitic nematodes of fishes from some freshwater and brackish-water localities in Honshu, Shikoku and Hokkaido, Japan, carried out in 1996-2009, yielded the following eight species: Hysterothylacium haze (Machida, Takahashi et Masuuchi, 1978) (Anisakidae), Paraquimperia sp., Pingus sinensis Hsu, 1933 (both Quimperiidae), Heliconema anguillae Yamaguti, 1935 (Physalopteridae), Rhabdochona angusticaudata sp. n., Rhabdochona zacconis Yamaguti, 1935 (both Rhabdochonidae), Ascarophis arctica Polyanskiy, 1952 (Cystidicolidae) and Eustrongylides sp. larvae (Dioctophymatidae). The new species, R. angusticaudata sp. n., described from the intestine of the Japanese eel Anguilla japonica Temminck et Schlegel in the Renjoji River, Shikoku, is mainly characterised by the presence of 14-16 anterior prostomal teeth, non-bifurcated deirids with rounded ends, the length of the left spicule (300-384 µm long), the right spicule with a dorsal barb and non-filamented eggs. The species of Paraquimperia Baylis, 1934 and A. arctica are reported from Japan for the first time. Based on light and scanning electron microscopical examinations, some new morphological data on H. haze, H. anguillae, R. zacconis and A. arctica are provided.

Twenty species (sixteen adult and four larval) of parasitic nematodes belonging to the Ascaridoidea, Camallanoidea, Cosmocercoidea, Dioctophymatoidea, Habronematoidea, Oxyuroidea, Seuratoidea, and Thelazioidea were collected from freshwater fishes of the Congo River basin in the Democratic Republic of the Congo and the Central African Republic in 2008 and 2012, respectively. Based on light and scanning electron microscopical examination, many species are redescribed in detail. This material also contained four previously unknown species, Labeonema longispiculatum sp. n. from Synodontis acanthomias Boulenger, Gendria longispiculata sp. n. from Schilbe grenfelli (Boulenger), G. sanghaensis sp. n. from Schilbe marmoratus Boulenger, and Cucullanus congolensis sp. n. from Auchenoglanis occidentalis (Valenciennes). The new species L. longispiculatum is mainly characterised by conspicuously long (210-228 µm) spicules, approximately twice as long as those in other congeners, the length (45-48 µm) of the gubernaculum and the host family (Mochokidae), whereas G. longispiculata by very long (1.2 mm) spicules, the shape of the oesophagus and cephalic vesicle, distribution of postanal papillae and the host family (Schilbeidae). Main characteristic features of G. sanghaensis are the presence of a hexagonal oral aperture surrounded by lip-like structures, the posterior portion of the oesophagus moderately expanded, spicules and the gubernaculum 414-438 µm and 54-57 µm long, respectively, deirids located at the level of the posterior end of the oesophagus and the absence of cervical alae. Cucullanus congolensis differs from congeneric species parasitising African freshwater and brackish-water fishes mainly in the absence of a ventral precloacal sucker and lateral preanal papillae, the presence of a large median precloacal papilla-like formation, spicules 480-489 µm long and the location of the excretory pore in the region of the oesophago-intestinal junction. Chabaudus Inglis et Ogden, 1965 is considered a junior synonym of Gendria Baylis, 1930 and, consequently, species listed in the former genus are transferred to the latter as G. alaini (Alfonso-Roque, 1981) comb. n., G. chabaudi (Inglis et Ogden, 1965) comb. n., G. dehradunensis (Rizvi, Bursey et Maity, 2016) comb. n., G. thysi (Puylaert, 1970) comb. n. and G. williamsi (Puylaert, 1970) comb. n. The findings represent many new host and geographical records.

Rhabdochona ( Rhabdochona ) longispicula Belous in Roytman, 1963 was detected from the intestine of the fish host Glyptothorax kurdistanicus from Greater Zab River near Aski-Kalak district, west of Erbil City during the period of May- July 2016 with prevalence of infection 17.39 % and mean intensity 3. This conistitutes the first record of this parasite in Iraq and Middle East. Also, G. kurdistanicus regarded as a new host for this nematode in the world.

Family RHABDOCHONIDAE Travassos, Artigas & Pereira, 1928 The Family Rhabdochonidae is represented in Canadian fishes by only one genus, namely, Rhabdochona. The phylogeny and biogeography of species of Rhabdochona from Canada and elsewhere in the Americas were investigated by Mejía-Madrid et al. (2007)., 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

Rhabdochonidae gen. sp. Site: intestine Host: Acipenser fulvescens Distribution: Saskatchewan Record: Choudhury et al. 1990

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.

Family Rhabdochonidae (Travassos, Artigas and Pereira, 1928 subfam.) Skrjabin, 1946 Rhabdochonidae gen. sp. (larvae) Host and record: Rhinella fernandezae (Co), Scinax nasicus (Cope, 1862) (Co), Scinax acuminatus (Cope, 1862) (Co). Site of infection: Gastric serous membrane. Material deposited: CECOAL 0 9020606 (R. fernandezae), CECOAL 0 4101102, 0 5042115 (S. nasicus), CECOAL 0 4101101 (S. acuminatus). References: Hamann et al. (2009 b; 2010; 2013); González & Hamann (2010 b). Life cycle: Amphibians act as paratenic hosts; amphipods and, especially, ephemeropters, as intermediate hosts. Adults are parasites of the digestive tract, the abdominal cavity and some internal organs especially of coldblooded vertebrates; they are rare in mammals (Anderson 2000).

González, Cynthya Elizabeth, Inés, Hamann Monika (2015): Checklist of nematode parasites of amphibians from Argentina. Zootaxa 3980 (4): 451-476, DOI: http://dx.doi.org/10.11646/zootaxa.3980.4.1

Family Rhabdochonidae (Travassos, Artigas and Pereira, 1928 subfam.) Skrjabin, 1946 Rhabdochonidae gen. sp. (larvae) Host and record: Rhinella fernandezae (Co), Scinax nasicus (Cope, 1862) (Co), Scinax acuminatus (Cope, 1862) (Co). Site of infection: Gastric serous membrane. Material deposited: CECOAL 0 9020606 (R. fernandezae), CECOAL 0 4101102, 0 5042115 (S. nasicus), CECOAL 0 4101101 (S. acuminatus). References: Hamann et al. (2009 b; 2010; 2013); Gonz��lez & Hamann (2010 b). Life cycle: Amphibians act as paratenic hosts; amphipods and, especially, ephemeropters, as intermediate hosts. Adults are parasites of the digestive tract, the abdominal cavity and some internal organs especially of coldblooded vertebrates; they are rare in mammals (Anderson 2000)., Published as part of Gonz��lez, Cynthya Elizabeth & In��s, Hamann Monika, 2015, Checklist of nematode parasites of amphibians from Argentina, pp. 451-476 in Zootaxa 3980 (4) on pages 462-463, DOI: 10.11646/zootaxa.3980.4.1, http://zenodo.org/record/233431, {"references":["Gonzalez, C. E. & Hamann, M. I. (2010 b) Larval nematodes found in amphibians from northeastern Argentina. Brazilian Journal of Biology, 71, 1089 - 1092. http: // dx. doi. org / 10.1590 / s 1519 - 69842010000500026","Anderson, R. C. (2000) Nematode Parasites of Vertebrates: Their Development and Transmission. 2 nd Edition. CAB International, Wallingford, Oxford, UK, 650 pp."]}

Specimens of three little-known species of Rhabdochona (Nematoda: Rhabdochonidae) were collected during occasional examinations of some freshwater fishes in India: R. (Rhabdochona) hellichi turkestanica (Skryabin, 1917) in Schizothorax sp. (Cyprinidae, Cypriniformes) from the Lodhomakhola and Rangit Rivers, West Bengal and Sikkim, respectively; R. (R.) hospeti Thapar, 1950 in Tor sp. (Cyprinidae) from the Rangit River; and R. (Globochona) mazeedi Prasad et Sahay, 1965 in Clupisoma garua (Hamilton) (Schilbeidae, Siluriformes) from the Farakka Dam Lake, West Bengal. Their detailed light and electron microscopical studies revealed some taxonomically important, previously not observed features and made possible their redescription. Fourth-stage larvae of R. hospeti are described for the first time. Rhabdochona hellichi turkestanica (syns. R. denudata filamentosa Bykhovskaya-Pavlovskaya, 1936, R. kashmirensis Thapar, 1950, R. schizothoracis Siddiqi et Khattak, 1984) is proposed as a subspecies, differing from the nominotypical subspecies R. hellichi hellichi (Srámek, 1901) mainly in the shape of the distal end of the left spicule, molecular data and geographical distribution. Rhabdochona moraveci Katoch et Kalia, 1991 (a homonym to R. moraveci Duggal et Kaur, 1987) is renamed R. indica nom. n. The following six species are considered new junior synonyms of R. hospeti: Comephronema [sic] mackiewiczi Malhotra et Rautela, 1984, Rhabdochona moraveci Duggal et Kaur, 1987, R. bifidum Kakar et Bilqees, 2007, R. uvaginus Kakar et Bilqees, 2007, R. bolani Kakar, Bilqees et Ahmad, 2008 and R. cephalodiverticula Kakar, Bilqees et Ahmad, 2008. Rhabdochona edentati Paul et Majumdar, 1994 is considered a species incertae sedis.

Two species of Rhabdochona Railliet, 1916 (Nematoda: Rhabdochonidae) were recorded from cyprinid fishes in the basin of the River Tigris, northern Iraq: adults of R. (R.) tigridis Rahemo, 1978 (emend.) from Capoeta trutta (Heckel) and Cyprinion macrostomum Heckel and fourth-stage larvae of R. (Globochona) sp. from C. macrostomum, Barbus barbulus Heckel and Barbus kersin Heckel. Light and scanning electron microscopical studies of this material made possible a detailed redescription of R. tigridis, which is characterised by 14 anterior prostomal teeth and filamented eggs. It differs from the most similar species, R. fortunatowi Dinnik, 1933, mainly in the presence of large deirids close to the prostom. R. grandipapillata Rahemo & Kasim, 1979 is considered a junior synonym of R. tigridis. Fourth-stage larvae of Rhabdochona (G.) sp., characterised by eight anterior prostomal teeth and the presence of caudal processes on the tail tip, represent the first record of a Rhabdochona species of the subgenus Globochona Moravec, 1972 in Iraq.

Rhabdochona ahuehuellensis n. sp. is described from the Balsas goodeid, Ilyodon whitei. The distinctive characters are cuticular elevations in the middle of the prostom, tricuspid ending of the distal part of the left spicule combined with a scoop shape, and an egg surface with limited, short subpolar filaments. The characters place the present species farther apart from species described from North America, except R. lichtenfelsi. This description brings the total number of species of Rhabdochona in the Mesa Central of Mexico to 4, suggesting that this genus has undergone speciation in response to basin fragmentation within the Mesa Central of Mexico.

Rhabdochona guerreroensis n. sp. is described on the basis of specimens recovered from the intestine of Sicydium multipunctatum (Regan) (Gobiidae, Perciformes) from 2 localities in Mexico. This species is characterized by 12 teeth in the prostom (occasionally 11), asymmetrical numbers of postanal papillae, a broad distal tip of the larger (left) spicule with a small bifurcation covered by narrow cuticular membrane, a smaller (right) spicule with a dorsal barb on its distal tip, and filamented eggs.

Rhabdochonidae gen. sp. Host and locality records: Scinax acuminatus (CO) and Scinax nasicus (CO) Distribution: Argentina Site of infection: stomach Stage: not reported Reference: Hamann, Kehr and González et al. (2009), and González and Hamann (2010b), Published as part of Campião, Karla Magalhães, Morais, Drausio Honorio, Dias, Olívia Tavares, Aguiar, Aline, Toledo, Gislayne De Melo, Tavares, Luiz Eduardo Roland & Silva, Reinaldo José Da, 2014, Checklist of Helminth parasites of Amphibians from South America, pp. 1-93 in Zootaxa 3843 (1) on page 34, DOI: 10.11646/zootaxa.3843.1.1, http://zenodo.org/record/4928492, {"references":["Gonzalez, C. E. & Hamann, M. I. (2010 b) Larval nematodes found in amphibians from northeastern Argentina. Brazilian Journal of Biology, 70 (4), 1089 - 1092. http: // dx. doi. org / 10.1590 / s 1519 - 69842010000500026"]}

Based on the original description, the nematode genus Piscinema Gambhir et Ng, 2014 and its type species, P. barakensis [sic] Gambhir et Ng, 2014 (probably a misidentified physalopterid larvae), are removed from the Philometridae, where they were allocated; they are considered a genus inquirendum and incertae sedis and a species inquirenda, respectively. The poorly described nematode Rhabdochona carpiae Nimbalkar, Deolalikar et Kamtikar, 2013 (Rhabdochonidae) appears largely fabricated and is regarded a species dubia.

A new nematode species, Rhabdochona (Rhabdochona) hypsibarbi n. sp. (Rhabdochonidae), is described from the intestine of the freshwater cyprinid fish Hypsibarbus wetmorei (Smith) in the Mekong River, Nakhon Phanom Province, northeast Thailand. It is mainly characterized by medium-sized, bifurcate deirids, the presence of 14 anterior prostomal teeth and distinct basal teeth, length ratio of the muscular and glandular portions of esophagus (1:6-9), length of the left spicule (669-774 μm), absence of a dorsal barb on the right spicule, length ratio of spicules (1:4.9-6.0), arrangement of genital papillae, and smooth eggs without filaments or swellings. In addition, specifically unidentified fourth-stage larvae of Rhabdochona (Rhabdochona) sp., morphologically similar to R. hypsibarbi, were recorded from the red-tailed tinfoil Barbonymus altus (Günther) (Cyprinidae) in the Mekong River, Nakhon Phanom Province, northeast Thailand. Rhabdochona hypsibarbi is the fourth nominal species of Rhabdochona Railliet, 1916 reported from fishes in Thailand and the second species of the nominotypical subgenus found in this country.

Duarte R., dos Santos-Clapp M.D. & Brasil-Sato M. de C. [Endohelminthes of Salminus hilarii Valenciennes (Actinopterygii: Bryconidae) and their ecological descriptors in the upper São Francisco River, Brazil.] Endohelmintos de Salminus hilarii Valenciennes (Actinopterygii, Bryconidae) e seus índices parasitários no rio São Francisco, Brasil. Revista Brasileira de Medicina Veterinária, 38(supl. 3):194-205, 2016. Programa de Pós-Graduação em Ciências Veterinárias, Anexo 1, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, BR 465, Km. 7, Campus Seropédica, RJ, Brasil, 23897-970. E-mail: michelledaniele@yahoo.com.br Among the fish encountered in the upper São Francisco river, Salminus hilarii, popularly in portuguese known as "dourado-branco" is a migratory briconid fish. A top carnivore in the food chain, that presents high commercial value and interest in fish farming and sport fishing. In this work, the endoparasites species of S. hilarii parasitic fauna were identified based on thirty-three specimens of fish from Três Marias reservoir, (18º12’51’’S 45º15’51’’W), State of Minas Gerais. Larval Eucestoda specimens (plerocercoids of Proteocephalidea), larval and adults/juveniles specimens of Nematoda were found. Amid of these nematodes, Hysterothylacium sp. was present in all the fish analyzed (Prevalence, P=100%) followed by Contracaecum sp. (P=60.6%), Spiroxys sp. (P=48.5%) and Goezia sp.1 (P=45.5%). The higher prevalence of Anisakidae larvae, mainly of Contracaecum sp., in relation to the other families is relevant. This study evidenced the importance of S. hilarii as an intermediate and paratenic host due to the great variety of Eucestoda and Nematoda larvae found; the adults and juveniles specimens from three important nematode families found in S. hilarii emphasize their paper as a potential definitive host due to their activities as a predatory fish in the reservoir. Salminus hilarii, from the upper São Francisco river, constitutes a new host for endoparasites species, Hysterothylacium sp., Contracaecum sp., Goezia spp., Spiroxys sp. and Rhabdochona acuminata, found in this work., Entre os peixes encontrados no alto rio São Francisco, Salminus hilarii, popularmente conhecido como dourado-branco, é um briconídeo migratório, carnívoro de topo na cadeia alimentar, que possui alto valor comercial, sendo de interesse na piscicultura e na pesca esportiva. Neste estudo as espécies de parasitos constituintes de sua fauna endoparasitária foram identificadas com base em trinta e três espécimes do reservatório de Três Marias (18º12’51’’S 45º15’51’’W), Minas Gerais. Foram encontrados espécimes larvais de Eucestoda (plerocercoides de Proteocephalidea) e espécimes larvais e adultos de Nematoda. Entre os nematoides, Hysterothylacium sp. ocorreu em todos os peixes (Prevalência, P = 100%), seguida de Contracaecum sp. (P = 60,6%), Spiroxys sp. (P = 48,5%) e Goezia sp.1 (P = 45,5%). A elevada prevalência das larvas de Anisakidae, especialmente de Contracaecum sp., é relevante. Neste estudo, a presença das larvas diversas de cestoides e nematoides em S. hilarii, revela sua importância como hospedeiro paratênico e intermediário; os espécimes adultos e juvenis representantes de três importantes famílias de nematoides em S. hilarii ressaltam seu papel como potencial hospedeiro definitivo decorrente de suas atividades como predador no reservatório. Salminus hilarii do alto rio São Francisco, constitui novo hospedeiro para as espécies: Hysterothylacium sp., Contracaecum sp., Goezia spp., Spiroxys sp. e Rhabdochona acuminata, encontradas nesse estudo.

A new species of Rhabdochona is described as a parasite of two endemic species of catfishes (Ictalurus dugesii and Ictalurus pricei) from two river basins in central and northern Mexico (Río Ameca and Río Tunal). Rhabdochona ictaluri sp. nov. is characterized by a combination of morphological traits that include the presence of basal teeth, bifurcated deirids, absence of a dorsal barb in left spicule and length ratio between spicules. The combination of these traits readily distinguishes the new species from all its congeners, including those species possessing 14 teeth in the prostom. The new species appears to be specific to freshwater ictalurids.

RHABDOCHONIDAE Travassos, Artigas & Pereira Beaninema nayaritense Caspeta��Mandujano, Moravec & Salgado��Maldonado, 2001 (E) Gall bladder. NAYARIT: Santiago: Cichlasoma beani (24)., 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":["24. 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."]}

Reexamination of the male holotype of the rhabdochonid nematode Rhabdochona leucaspii Kritscher, 1979, originally described from the intestine of the cyprinid fish Leucaspius prosperi [= Ladigesocypris ghigii (Gianferrari)] from Rhodes Island, Greece, confirmed its morphological and biometrical identity with Rhabdochona denudata (Dujardin, 1845), a common and widespread parasite of cyprinids and some other fishes in palaearctic Eurasia. Consequently, R. leucaspii is considered a junior synonym of R. denudata.

Helminthological examination of specimens of the freshwater fishes Bryconamericus iheringi Boulenger, 1887 (Characidae) and Jenynsia multidentata (Jenyns, 1842) (Anablepidae), collected from Medina River, Province of Tucuman, Argentina, revealed the presence of 2 species of parasitic nematodes, Rhabdochona fabianae n. sp. and Rhabdochona acuminata (Molin, 1860) (Rhabdochonidae). Rhabdochona fabianae n. sp. was characterized by the presence of 16 anterior teeth in the prostom and filamented eggs in females. Rhabdochona acuminata was recorded for the first time in the north of Argentina.

Rhabdochona (Rhabdochona) acuminata is redescribed from specimens parasitizing Diplomystes mesembrinus (Siluriformes: Diplomystidae) and Percichthys trucha (Perciformes: Percichthyidae) from the Chubut River, Patagonia, Argentina. The present report is the first record of this nematode in D. mesembrinus; it also confirms P. trucha as host and Patagonia as a region of distribution for R. (R.) acuminata. Morphological features of the species were described using light and scanning electron microscopy. Compared with previous descriptions from Brazil, a very similar morphology is observed. However, a large morphometric variability is found, mainly in body size, spicule ratio, and number and arrangement of pre- and postcloacal papillae. Fil: Cremonte, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina Fil: Navone, Graciela Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina Fil: Gosztonyi, Atila Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Kuba, Luisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina

Description de Fellicola longispiculus n. g., n. sp., parasite de la vesicule biliaire du Poisson Coryphaenoides rupestris recolte au large des iles Feroe (Atlantique Nord). Le nouveau genre appartient a la famille des Rhabdochonidae. Il est proche des genres Johnstonmawsonia, Vasorhabdochona et Pancreatonema, mais en differe par la presence d'epaississements longitudinaux sur la paroi interne de la partie anterieure dilatee du pharynx

Trichospirura aethiopica n. sp. is described from unidentified tubular structures (pancreatic ducts?) near the stomach of the murid Malacomys longipes Milne-Edwards, 1877 in Gabon. The extremely long and narrow buccal capsule, posterior position of the vulva, unequal spicules and absence of caudal alae readily identified the specimens as belonging to Trichospirura Smith & Chitwood, 1967, but a combination of several characters distinguished them from the described species in this genus. Males of the new species are characterized by the absence of precloacal papillae, the presence of four pairs of postcloacal papillae and a left spicule length of 165–200 μm. With only five nominal and one unnamed species, the host range of Trichospirura extends into the Neotropical, Indo-Malayan and Ethiopian Realms and comprises three classes of vertebrates, Amphibia, Reptilia and Mammalia, suggesting a larger species diversity than that currently recorded. Detection is difficult as predilection sites are often outside the gut lumen. It was noted that, irrespective of their geographic origin, species from mammals share certain characters (shorter left spicule and absence of precloacal papillae) that oppose them to those from amphibians and reptiles. A hypothesis for the origin of Trichospirura in mammals through a remote host-switching event in tupaiids in southern Asia, likely facilitated by the intermediate hosts, and for their subsequent migration to the Ethiopian and finally Neotropical Realm is proposed. Regarding the two species from anurans and saurians in the Antilles, one or two host-switching events are considered equally possible, based on morphological characters.

Based on original data gathered from fieldwork during the last years and from previous records from all published accounts, a checklist of the adult nematode parasites of freshwater fishes from Mexico is presented. The checklist is organized as a nematode-host list and comprises taxonomic and geographic distributional information. In total, the checklist includes 70 taxa (50 identified at species level) pertaining to 13 families. These taxa have been collected from 107 freshwater fish taxa in 198 localities along the Mexican Republic. The information we provide herein indicates that sampling effort has been concentrated in Central and South East Mexico, with the Northern region remaining mostly unexplored. The proportion of endemic nematodes is high in the country (74%, i.e., 37 of the 50 taxa identified at species level). The family Rhabdochonidae displays the highest species richness (12 species), and Rhabdochona kidderi is the most widespread nematode species in the country. Cichlids represent the host group with the largest number of samples in Mexico. Finally, we present a list containing new records of larval nematodes from localities in the states of Michoacán, Nayarit, Oaxaca, Tamaulipas and Veracruz.

A new species of Rhabdochona from 2 species of freshwater fishes, Alloophorus robustus and Goodea atripinnis, is described from 2 lakes of the Mesa Central of Mexico. Rhabdochona lichtenfelsi n. sp. belongs to a group of species possessing inconspicuous bifurcated deirids and a prostom armed with 10 large teeth. It is distinguished from them because the left spicule is shorter, the tip is bifurcate, and both spicules lack a reflected dorsal barb. The new species most closely resembles Rhabdochona catostomi and Rhabdochona milleri but differs from them because the former possesses a left spicule tip with ventral barb, right spicule with reflected distal barb, and 5 pairs of postanal papillae, whereas R. milleri has 14 prostomal teeth, eggs rounded, and left spicule with slightly outlined bifurcation and right with a dorsal barb. Previous records of R. milleri in Mexico must be referred to R. lichtenfelsi.

A total of 933 mottled sculpins, Cottus bairdi Girard (Cottidae), was examined for Rhabdochona cotti from April 1983 through November 1986 from 3 localities (up-river, middle, down-river) in the Ford River in Michigan's Upper Peninsula. The prevalence and mean intensity of R. cotti were highest in sculpins from the middle (37%) and up-river localities (2.0), respectively. The intensity of R. cotti significantly increased with host length at the middle and down-river localities. Rhabdochona cotti did not exhibit consistent seasonal infection patterns at each location when the data were analyzed seasonally within and between years. Gravid R. cotti infected sculpins in most seasons of each year at the up-river and middle localities. The limited occurrence of R. cotti in sculpins in North America is summarized and discussed.

Trichospirura amphibiophila n. sp. (Nematoda) is described from the abdominal cavity (encapsulated near the liver) of the frog Eleutherodactylus martinicensis (Anura: Leptodactylidae) from the island of La Desirade in the French Antilles. It is characterized by the length of its spicules (459 microns and 90 microns) and their length ratio (1:5), by the presence of deirids and 7 pairs of caudal papillae in the male (2 preanal and 5 postanal), and by the site of localization (abdominal cavity) in the host. Trichospirura amphibiophila is the first known species of the genus parasitizing amphibians.

Rhabdochona (Rhabdochona) parastromatei sp.n. is characterized by its relatively large body size, 16 teeth in pros tome, right spicule 0.48-0.50 mm and left 0.10-0.12 mm in length, 9–10 pairs of caudal papillae, a single adanal papilla, eggs in female 0.029-0.044 by 0.018-0.025 mm in size, and by having a marine fish host.

A new genus and species of nematode, Pancreatonema torriensis , from the pancreatic duct of Raja naevus caught off Aberdeen and north-west Scotland is described and aspects of its biology are discussed. According to the classification of Skrjabin, Sobolev & Ivashkin (1967) [Spirurata of animals and man and the diseases caused by them (4). Essentials of Nematodology , Vol. 16 (I.P.S.T. Translation No. 5904, Jerusalem, 1971)]it belongs to the family Rhabdochonidae, sub-family Prosungulonematinae, and is closely related to the genus Johnstonmawsonia . The taxonomy of the Prosungulonematinae is confused but it is suggested that Johnstonmawsonia should at present be restricted to those species of the genus described from marine teleosts, and that the species from freshwater teleosts should be included in the genus Prosungulonema .

Male specimens found with females of Spinitectus oviflagellis Fourment, 1884, in the intestine of Gadus merlangus have been described and compared with two other males of Spinitectus. Considering the differences they are regarded as males of S. oviflagellis.

Campião, Karla Magalhães, Morais, Drausio Honorio, Dias, Olívia Tavares, Aguiar, Aline, Toledo, Gislayne De Melo, Tavares, Luiz Eduardo Roland, Silva, Reinaldo José Da (2014): Checklist of Helminth parasites of Amphibians from South America. Zootaxa 3843 (1): 1-93, DOI: http://dx.doi.org/10.11646/zootaxa.3843.1.1

The development of Spinitectus micracanthus is described in the intermediate host, Hexagenia sp. (Insecta: Ephemeroptera), and in the definitive host, Lepomis macrochirus. Larval development occurs primarily in the abdominal muscles of Hexagenia sp., and encysted, third-stage larvae were present in the muscles 20 days postinfection. Males with sperm in the reproductive tract were recovered from the intestine of the definitive host 26 days postinfection, and females containing eggs were recovered from the intestine 36 days postinfection of the definitive host. Infective larvae of S. micracanthus were compared with larvae of S. gracilis obtained from naturally infected Hexagenia sp.