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Two new species of the genus Acantholaimus (Nematoda, Chromadoridae) are described from the South Atlantic, in the Santos Basin off the slope of southeastern Brazil. Acantholaimus pugious sp. n. is characterized by a narrow and elongated anterior end; teeth that are thin and long stylet-like (two in number), amphidial fovea located far from the anterior end and occupying most of the corresponding body diameter. Acantholaimus bidentatus sp. n. is characterized by a narrow anterior end, cuticle with more evident dots on both body extremities (up to amphidial fovea and tail); two long, protractible thin teeth (similar to stylet), with curved proximal part. The two species are similar in the shape of the teeth. The teeth morphology may be correlated to the process of adaptive convergence of these species. An emended diagnosis of the genus is provided.

Genus Acantholaimus Allgén, 1933 (modified after Venekey et al. 2019) Diagnosis: Cuticle punctate, with transverse rows of dots; lateral differentiation may be presented as enlarged dots arranged irregularly, or more sparsely, or in transverse or longitudinal rows. Head sensilla arranged in three circles, posterior two being at almost the same level and usually setiform (sometimes jointed). Anterior sensilla are often papilloid and indistinct. Somatic setae may be present or absent. Amphidial fovea large, round with interrupted posterior rim or nearly comma-shaped (spiral in one species). Buccal cavity armed with two or more solid teeth (indiscernible in two species), teeth minute or large, often eversible (two elongated and narrow stylet-like teeth present in two species). Spicules of a peculiar construction - flattened and strongly broadened proximally. Rodshaped gubernaculum without apophysis and bifurcated at its distal end. Spermatozoa giant, pear-shaped, often structurally complex. No precloacal supplements. Tail long, filiform. Marine, mostly deep-sea., Published as part of Manoel, Alex, Esteves, André Morgado & Neres, Patrícia Fernandes, 2022, Two new species of Acantholaimus (Nematoda, Chromadoridae) from the deep southeastern Atlantic (Santos Basin), pp. 238-256 in Zootaxa 5209 (2) on page 241, DOI: 10.11646/zootaxa.5209.2.5, http://zenodo.org/record/7325946, {"references":["Allgen, C. A. (1933) Freilebende Nematoden aus dem Trondhjemsfjord. Capita Zoologica, 4 (2), 1 - 162.","Venekey, V., Gheller, P. F., Kandratavicius, N., Cunha, B. P., Vilas-Boas, A. C., Fonseca, G. & Maria, T. F. (2019) The state of the art of Chromadoridae (Nematoda. Chromadorida): a historical review. diagnoses and comments about valid and dubious genera and a list of valid species. Zootaxa, 4578 (1), 1 - 67. https: // doi. org / 10.11646 / zootaxa. 4578.1.1"]}

Acantholaimus bidentatus sp. n. (Table 2; Figs. 5–8) Material studied. Holotype male (MOUFPE 0015), paratype juvenile (MOUFPE 0016). Type locality. Santos Basin, Rio de Janeiro, Brazil. Holotype male and paratype juvenile: 24°74′00″S 43°15′11″W (2000 m depth), Etymology. In reference of the number of teeth (two). Holotype male. Body cylindrical (1116 μm long excluding tail) and attenuated at extremities (Fig. 7A), head diameter corresponding to 23% of maximum body diameter (Fig. 5A). Cuticle punctuated with larger and more evident dots in anterior region up to amphidial fovea end, and in tail (Figs. 5G, 7C, 7D). Lateral differentiation not observed. Cuticular pores randomly scattered, extending along entire body length. Anterior sensilla arranged according to 6+6+4 pattern: six inner labial papillae, six outer labial (6 µm) and four cephalic setae (8 μm long), corresponding to approximately 1.2 times the head diameter; last two circles (external labial and cephalic) almost at the same level (Figs. 5B, 7C). Ventrally spiral amphidial fovea rounded with posterior interruption (single-spiral), located 19.2 µm (2.67 x head diameter) from anterior end and occupying 79% of corresponding body diameter (Figs. 5B, 7C). Four cervical setae, typically found in the genus, located posteriorly to each amphidial fovea (2 in the latero-subdorsal region and 2 in the latero-subventral region) and difficult to see. Four pores, in the same position as the typical cervical setae, are visualized (Figs. 5D, 5E). Somatic setae present only in precloacal region, two at the same level and distant from the cloaca (20 µm), positioned in the latero-subdorsal and latero-subventral region and one setae ventrally located (12 µm of the cloaca) (Fig. 7D). Buccal cavity reduced. Cheilostom rugae indiscernible under a light microscope. Two long and thin stylet-like protractible teeth (37 µm long); proximal part of teeth curved towards the dorsal and ventral regions of the body (Figs. 5C, 7C). Pharynx (164 μm long) with basal bulb (48 µm length x 22.5 μm diameter) occupying 29% of pharynx length (Fig. 7B). Cardia embedded in intestine. Nerve ring situated at 59% of the pharyngeal region length. Ventral gland and secretory-excretory pore not observed. Reproductive system with single anterior outstretched testis on right-hand side of intestine (179 μm long), occupying about 16% of body length (excluding tail) (Fig. 7A). Spicules curved, expanded and flattened in proximal portion (Figs. 5F, 7E). Gubernaculum with proximal portion slightly curved and bifurcated distal end (Fig. 7E). Apophysis absent. Precloacal supplements absent. Caudal glands difficult to differentiate. Tail conical-cylindrical with long filiform portion (Figs. 5G, 7D). Distal portion of the tail is broken off. Paratype juvenile. The juvenile analyzed may be in the early stage of development, because the genital primordium is not visible. Juvenile shared the following adult features: Body cylindrical and attenuated at extremities (617 μm long) (Figs. 6A, 8A). Punctuated cuticle, the points are so delicate that it is difficult to see at the cloacal region. Dots larger and more evident in the tail (Fig. 8C). Cuticular pores not observed. Cephalic arrangement similar to the male (Fig. 8B). Somatic and cervical setae absent. Ventrally spiral amphidial fovea rounded with posterior interruption (single-spiral), located 9.6 µm (2 x head diameter) from anterior end and occupying 67% of corresponding body diameter (Figs. 6C, 8B). Buccal cavity similar to that observed in the male. Two long and thin protractible teeth which resemble a stylet in shape (29.4 µm) (Figs. 6B, 8B). Pharynx similar to that in adults (120.6 μm). Tail conical-cylindrical with filiform end portion (Figs. 6D, 8C). Spinneret short. Diagnosis. Anterior end narrow, cuticle with more evident dots in anterior region (up to amphidial fovea end) and tail; cuticular pores do not present a specific distribution pattern. Anterior sensilla arranged with six inner labial papillae, six outer labial and four cephalic setae (last two circles almost at the same level). Teeth long and thin (similar to stylet), protractile, with proximal part of teeth curved, amphidial fovea occupying most of the corresponding body diameter (67–79%), located 2–2.67 times the head diameter from the anterior end. Differential diagnosis. Firstly, it is important to establish that only the males of the species mentioned in this section were compared, since the females were not found. The new species shares the following features with Acantholaimus iubilus: cuticle punctuated with larger and more evident dots in anterior and tail region; cloacal diameter (30 µm in A. iubilus and 30.9 µm in the new specie) and the amphid diameter (12 µm in A. iubilus and 13.2 µm in A. bidentatus sp. n.). However, these species differ in terms of the proportion that the amphidial fovea occupy in relation to the corresponding body diameter (near a half in A. iubilus vs more than ¾ in the new species) and the number of teeth observed in the new species (2) is smaller than the number described for A. iubilus (5). Moreover, lateral differentiation is absent in A. bidentatus sp. n. The new species resembles the males of Acantholaimus robustus, in terms of the number of teeth in the pharyngostome (2); the absence of lateral differentiation and the amphidial diameter (11–14 µm in A. robustus and 13.2 µm in the new species). However, the males of A. robustus differ from those of A. bidentatus sp. n. in the following features: presence of numerous somatic setae along the entire body; the amphidial fovea occupy a smaller proportion in relation to the corresponding body diameter (52–70% in A. robustus vs 79% in A. bidentatus sp. n.) and present longer spicules. Acantholaimus pugious sp. n. resembles A. bidentatus sp. n. in terms of the number of teeth in esophastoma (2) and the proportion that the amphidial fovea occupy in relation to the corresponding body diameter (71–81% in A. pugious sp. n. and 79% in A. bidentatus sp. n.). Meanwhile, the body length of A. pugious sp. n., without the tail, is between 1.8–2 times shorter and maximum body diameter between 2.2–2.8 times smaller when compared to A. bidentatus sp. n., Published as part of Manoel, Alex, Esteves, André Morgado & Neres, Patrícia Fernandes, 2022, Two new species of Acantholaimus (Nematoda, Chromadoridae) from the deep southeastern Atlantic (Santos Basin), pp. 238-256 in Zootaxa 5209 (2) on pages 248-253, DOI: 10.11646/zootaxa.5209.2.5, http://zenodo.org/record/7325946, {"references":["Miljutina, M. A. & Miljutin, D. M. (2012) Seven new and four known species of the genus Acantholaimus (Nematoda: Chromadoridae) from the abyssal manganese nodule field (Clarion-Clipperton Fracture Zone. North-Eastern Tropical Pacific). Helgoland Marine Research, 66, 413 - 462. https: // doi. org / 10.1007 / s 10152 - 011 - 0282 - z"]}

Acantholaimus pugious sp. n. (Table 1; Figs 1–4) Material studied. Holotype male (MOUFPE 0013), 1 paratype female (MOUFPE 0014), 2 paratypes males (220 NM LMZOO-UFPE). Type locality. Santos Basin, Rio de Janeiro, Brazil. Holotype male and paratype female: 24°74′00″S 43°15′11″W (2000 m depth), Etymology. In reference to the shape of the teeth, similar to a stylet. Holotype male. Body cylindrical 888 μm long (706 μm excluding tail) (Figs. 1A, 3A). Body attenuated at extremities, strongly narrowed anterior end (Figs 1B, 3B). Punctuated cuticle, the points are so delicate that it is difficult to see. Cuticular pores not observed. Anterior sensilla arranged in the 6+6+4 pattern: six inner labial papilliform sensilla, six outer labial papilliform sensilla and four cephalic setiform sensilla (2 μm long) (Fig. 3C), corresponding to 83% of head diameter. Ventrally spiral amphidial fovea (single-spiral), rounded with posterior interruption, located 26 µm (8.7 x head diameter) from anterior end and occupying 71% of corresponding body diameter (Figs. 1B, 3C). Cervical setae present, however it is likely that some of these have been lost. In the holotype only one pair of cervical setae were observed, the first (latero-subdorsal) is 17 µm and the second (latero-subventral) is 21 µm from the posterior edge of the amphidial fovea. Buccal cavity reduced. Cheilostom rugae indiscernible under a light microscope. Two long and thin protractible stylet-like teeth (42 µm), about 19% of pharynx length (Fig. 3C). Pharynx (220 μm long) with narrowing in the second third of its length, and expanded in the final third forming an elongated basal bulb (Fig. 3B). Bulb occupying 23.4% of pharynx length. Cardia embedded in intestine. Nerve ring situated at 51% of the pharynx length, from anterior end (Fig. 3B). Ventral gland and secretory-excretory pore not observed. Reproductive system with single anterior outstretched testis on right side of intestine (208 μm), occupying about 29% of body length (excluding tail) (Fig. 3A). Spicules curved, expanded and flattened in proximal portion (Figs. 1C, 3E). Gubernaculum narrow, slightly curved. Distal region so thin that it is not possible to differentiate the final bifurcation. Precloacal supplements absent. Mature spermatozoid measuring 29 x 6 μm. Three caudal glands. Tail conical-cylindrical with long filiform portion (177 µm or 14 x cloacal diameter) (Figs. 1D, 3D). Paratype female. Similar to male. Body measuring 979 μm in length (751 μm excluding the tail), and maximum diameter 12 μm (Fig. 4A). Cephalic sensilla equivalent to 50% corresponding body diameter (Fig. 4C). Amphidial fovea, occupying 67% of corresponding body width and located 15 µm (3.75 x head diameter) from anterior end (Figs. 2A, 2C, 4C). Its size is similar to that of the male, but in females it is located more anteriorly on the body. Buccal cavity and pharynx similar to that of male (Fig. 4B). Teeth resemble a stylet in shape, as in males, but are smaller in the females (5 μm, about 3% of pharynx length) (Figs. 2C, 4C). Basal bulb occupying 75% of the corresponding body diameter and 16% of pharynx length (Fig. 4B). Nerve ring not visible. Ventral gland and secretory-excretory pore not observed. Cardia embedded in intestine. Vulva located 493 μm from anterior end, at 66% of body length, from anterior end excluding the tail. Two opposed, reflexed and antidromous ovaries (anterior ovary lying to right of intestine, posterior ovary to left of intestine) (Figs. 2B, 4D). Anterior and posterior ovary measuring respectively 288 and 156 μm. Tail conical-cylindrical with long filiform portion (Fig. 2D). Diagnosis. Acantholaimus pugious sp. n. is characterized by narrow and elongated anterior end, two thin and long stylet-like teeth, amphidial fovea far from the anterior end (3.8–8.6 x head diameter) occupying most of the corresponding body diameter, cuticle with delicate and faint punctations and cervical setae without a specific distribution pattern. Differential diagnosis. The new species shares the following features with Acantholaimus microdontus: the relatively large amphidial fovea (78–85% of corresponding body diameter in A. microdontus and 67–81% in A. pugious sp. n.); elongated basal bulb and de Man’s ratio c (4.4–5.1 in A. microdontus and 3–5 in the new specie). However, A. microdontus has distinct characteristics such as maximum body diameter about 2–4 times wider than A. pugious sp. n.; the length of the spicules (25–32 μm in A. microdontus vs 18–21 μm in A. pugious sp. n.), and the de Man’s ratio a 1.8–2.6 times smaller than in the new species. Acantholaimus veitkoehlerae shares with the new species features such as: presence of the elongated basal bulb; amphidial fovea diameter (6–9 μm in A. veitkoehlerae and 5–8 μm in the new species); de Man’s ratio b (4.6–6.6 µm in A. veitkoehlerae and 4–6 µm in A. pugious sp. n.). Nevertheless, A. veitkoehlerae presents numerous somatic setae along the entire body, with these setae absent in the new species; gubernaculum 1.7–3.3 times longer that in A. pugious; buccal cavity armed with five sclerotized onchia usually found in the genus, while the new species possesses two onchia resembling a stylet in shape. Acantholaimus angustus resembles the new species in terms of the presence of an elongated bulb, de Man’s ratio b (5–6.2 in A. angustus and 4–6 in A. pugious), and ratio between total body length and tail length (4.7–5.5 in A.angustus and 3–5 in A. pugious). Yet, A. angustus differs from A. pugious sp. n. in the following features: six outer labial sensilla visible in A. angustus (6 μm long) whereas in A. pugious the sensilla are papilliform; A. angustus possesses four setae close to the amphidial fovea, while in A. pugious the corresponding structures are absent; cephalic setae in A. angustus are 5 times longer than in the new species; the amphidial fovea in males of A. angustus is located at 0.93 times head diameter from the anterior end, while in A. pugious the amphids are 6–8.7 times head diameter from anterior end.

Chromadora serrambi sp. nov. (Figures 1–4, Table 1) http://zoobank.org/ 4FDD4AB1-F6F8-4A3A-89F8-7EDB0330B8A2 Type material. Holotype male (MOUFPE 0001), paratype female (MOUFPE 0002), others paratypes: 5 males (443–447 NM LMZOO-UFPE) and 5 females (448–452 NM LMZOO-UFPE). Type Locality. Serrambi beach (S 8°33’31.5” W 35°00’16.7”), located on the southern coast of the State of Pernambuco, in the Northeastern region of Brazil. Etymology. The specific epithet ‘serrambi’ is given because this species was found in a coral reef located on Serrambi beach. In addition, the species has a unique characteristic (autapomorphy) and for this reason the collection site was chosen for its name. Description. Holotype (Male). Body cylindrical, 597 µm long. Maximum body diameter 23 µm, anterior region attenuated, head diameter 9 µm (45% of body diameter in pharynx end). Annulated cuticle with transversal rows of small dots. Lateral longitudinal differentiation represented by four rows of larger and more spaced dots. This pattern is homogeneous throughout the body extension. Cephalic arrangement 6+6+4, inner and outer labial sensilla papilliform; cephalic setiform sensilla measuring 0.7 times head diameter. Amphideal fovea difficult to see (the same condition was observed in all analyzed specimens). Buccal cavity armed with three solid teeth, one dorsal and two ventral, dorsal tooth larger and curved. Secretory–excretory pore located 9 µm from anterior end (0.7 times head diameter). Secretory–excretory gland posterior to pharynx with two cells present, one well developed measuring 46 µm (proximal) and one of reduced size (7 µm). Ocelli situated 19 µm from anterior end and nerve ring located 65 µm from anterior end, posterior to middle of pharynx length. Pharynx with rounded bulb, occupying 23% of pharynx length; anterior muscle interruption can be viewed. The reproductive system with a single outstretched testis. Spicules 1.3 times the cloacal body diameter, curved and cephalated. Gubernaculum narrow, occupying 68% of spicule length, with expanded distal portion, embracing the spicules. Pre-cloacal supplements absent. Tail conical-elongated measuring 6.1 times cloacal body diameter, with a small spinneret (4 µm). Paratypes (Females). Very similar to male. Reproductive system amphidelphic with reflexed ovaries with branches bent in opposite directions. Anterior gonad to the right of the intestine and the posterior gonad to the left of the intestine. Vulva located anteriorly to mid-body region (47–48.7% of total length). Tail 5.8–7.4 times anal body diameter. Diagnosis. Chromadora serrambi sp. nov. is characterized by a simple bulb, cephalic setae 0.6–0.7 times head diameter in male and 0.7–0.9 in female. Secretory-excretory pore 0.7–0.9 times head diameter from anterior end. Ocelli present. Spicules 1–1.3 times cloacal body diameter. Gubernaculum narrow (60–68% of spicule length), with expanded distal portion, embracing the spicules. Precloacal supplements absent. Tail conical-elongated with a small spinneret (5.5–6.4 times cloacal body diameter in male and 5.8–7.4 times anal body diameter in female). Differential diagnosis (Relationships). Chromadora serrambi sp. nov. is the only Chromadora species where pre-cloacal supplements are absent which facilitates its identification. In relation to the gubernaculum, C. macrolaimoides presents a similar shape (distal expansion), however it seems to be less developed (smaller and less sclerotized) in the new species (11–14 µm vs. 18–23 µm). The anterior region (position of the ocelli and secretoryexcretory pore, bulb shape) is similar to that observed in C. nudicapitata redescribed by Kito (1978a,b)., Published as part of Neres, Patrícia Fernandes, Santos, Paulo Jorge Parreira Dos & Esteves, André Morgado, 2021, New chromadorid nematodes from Brazilian coral reefs: a taxonomic contribution to Chromadora Bastian, 1865, pp. 47-79 in Zootaxa 5032 (1) on pages 50-56, DOI: 10.11646/zootaxa.5032.1.2, http://zenodo.org/record/5477471, {"references":["Kito, K. (1978 a) Studies on the free-living marine nematodes from Hokkaido, III. Journal of the Faculty of Science, Hokkaido University, Series VI, Zoology, 21 (2), 248 - 261."]}

Chromadora pernambucana sp. nov. (Figures 5–8, Table 2) http://zoobank.org/ 569F0CD3-628F-4D7C-8E0D-776A76793B21 Type material. Holotype male (MOUFPE 0003), paratype female (MOUFPE 0004), others paratypes: 5 males (453–457 NM LMZOO-UFPE) and 5 females (458–462 NM LMZOO-UFPE). Type Locality. Serrambi beach (S 8°33’31.5” W 35°00’16.7”), located on the southern coast of the State of Pernambuco, in the Northeastern region of Brazil. Etymology. The specific epithet ‘pernambucana is given because this species was found in Serrambi beach, Pernambuco State (Northeastern Brazil). Description. Holotype (Male). Body cylindrical 608 µm long. Maximum body diameter 23µm, anterior region attenuated, head diameter 9 µm (42% of body diameter in pharynx end). Annulated cuticle with transversal rows of small dots. Lateral longitudinal differentiation represented by four rows of larger and more spaced dots. In tail region, these larger dots appear to be closer to each other, forming an almost a longitudinal line. Cephalic arrangement 6+6+4, inner and outer labial sensilla papilliform; cephalic setiform sensilla measuring 0.4 times head diameter. Amphideal fovea transversely elliptical occupying 44.4 % of corresponding body diameter, located 3 µm from anterior end. Buccal cavity armed with three solid teeth, one dorsal and two ventral, dorsal tooth larger. Secretory–excretory pore at cephalic setae level (3 µm from anterior end). Secretory–excretory gland posterior to pharynx with two cells present, one well developed measuring 72.5 µm (proximal) and one of reduced size (10.5 µm). Ocelli not observed (the same was found in all analyzed specimens). Nerve ring located 66 µm from anterior end, posterior to middle of pharynx length. Pharynx with terminal bulb (17.5 µm in diameter), occupying 24.5% of pharynx length. The reproductive system with a single outstretched testis. Spicules curved 1.4 times the cloacal body diameter. Gubernaculum almost the size of the spicule (83% of spicule length), embracing it in its posterior half; distal portion pointed. Three pre-cloacal supplements, two cup-shaped (2 µm) little sclerotized, located 8 µm and 18.5 µm from the cloaca, and one papilla-shaped situated just before the cloaca. Post-cloacal supplement (papilla like) 50 µm from cloaca (0.6 times tail length). Tail conical measuring 4.8 times cloacal body diameter, with a small spinneret (3 µm). Paratypes (Females). Very similar to male, but its tail is slightly larger 5.3–6.2 times anal body diameter. Reproductive system amphidelphic with reflexed ovaries with branches bent in opposite directions. Anterior gonad to the right of the intestine and the posterior gonad to the left of the intestine. Vulva located next to mid-body region (49–51% of total length). Diagnosis. Chromadora pernambucana sp. nov. is characterized by simple bulb, cephalic setae 0.4–0.5 times head diameter. Secretory-excretory pore at cephalic setae level. Ocelli not observed. Spicules 1.3–1.4 times cloacal body diameter. Gubernaculum almost the size of the spicule (73–84% of spicule length), embracing it in its posterior half; distal portion pointed. Three pre-cloacal supplements, two cup-shaped, weakly sclerotized and one papillashaped situated just before the cloaca. Distance between supplement one (S1) and supplement two (S2) 0.13–0.22 times tail length and between S2 and papilla (supplement 3 – S3) 0.07–0.2 times tail length. Post-cloacal papilla next to tail end (0.6–0.8 times tail length). Tail conical with a small spinneret (4.5–5.1 times cloacal body diameter in male and 5.3–6.2 times anal body diameter in female). Differential diagnosis (Relationships). Chromadora pernambucana sp. nov. it is differentiated from other species of the genus by the shape of the gubernaculum, which extends to middle its length, embracing the spicules, and with a distal region point; in addition, it has three supplements of which two are cup-shaped (small and slightly sclerotized) and another pre-cloacal papilla very close to the cloaca. Chromadora micropapillata also presents this papilla proximate and anterior to the cloaca, but these species differ in the shape of the gubernaculum., Published as part of Neres, Patrícia Fernandes, Santos, Paulo Jorge Parreira Dos & Esteves, André Morgado, 2021, New chromadorid nematodes from Brazilian coral reefs: a taxonomic contribution to Chromadora Bastian, 1865, pp. 47-79 in Zootaxa 5032 (1) on page 56, DOI: 10.11646/zootaxa.5032.1.2, http://zenodo.org/record/5477471

Genus Chromadora Bastian, 1865 (emended after Venekey et al. 2019) Diagnosis. Cuticle with homogeneous punctation pattern along the body, with lateral differentiation of larger dots. Transverse slit-like amphideal fovea. Buccal cavity usually with three solid teeth, the dorsal tooth larger than ventrosublateral teeth. Occasionally, only one dorsal tooth is observed. Ocelli may be present. Pharynx with terminal bulb, simple or double. Males usually with cup-shaped precloacal supplements. The genus is very similar to Atrochromadora, the main difference is the amphideal fovea shape which is more circular in the current genus; the variable number of teeth (one or three) is also another feature that can be easily used in the identification of Chromadora species. Marine., Published as part of Neres, Patrícia Fernandes, Santos, Paulo Jorge Parreira Dos & Esteves, André Morgado, 2021, New chromadorid nematodes from Brazilian coral reefs: a taxonomic contribution to Chromadora Bastian, 1865, pp. 47-79 in Zootaxa 5032 (1) on page 49, DOI: 10.11646/zootaxa.5032.1.2, http://zenodo.org/record/5477471, {"references":["Bastian, H. C. (1865) Monograph of the Anguillulidae, or Free Nematoids, Marine, Land, and Freshwater; with Descriptions of 100 New Species. Transactions of the Linnean Society of London, 25 (2), 73 - 184. https: // doi. org / 10.1111 / j. 1096 - 3642.1865. tb 00179. x","Venekey, V., Gheller, P. F., Kandratavicius, N., Cunha, B. P., Vilas-Boas, A. C., Fonseca, G. & Maria, T. F. (2019) The state of the art of Chromadoridae (Nematoda, Chromadorida): A historical review, diagnoses and comments about valid and dubious genera and a list of valid species (2019). Zootaxa, 4578 (1), 1 - 67. https: // doi. org / 10.11646 / zootaxa. 4578.1.1"]}

Key to species of Epacanthion 1 Spicules without gubernaculum.................................................................................................................................... 2 - Spicules with gubernaculum......................................................................................................................................... 3 2 Spicules long (more 100 µm), one pre-anal supplement................................................................... E. agubernaculus - Spicules short (less 100 µm), without pre-anal supplement............................................................................... E. oliffi 3 Spicules short, 2-5 or fewer anal diameters long.......................................................................................................... 4 - Spicules long, 3 or more anal diameters long............................................................................................................. 14 4 Pre-anal supplement present......................................................................................................................................... 5 - Pre-anal supplement absent........................................................................................................................................ 12 5 Nine to 14 small, setose pre-anal supplements............................................................................................................. 6 - Only one pre-anal supplement...................................................................................................................................... 7 6 Distance between tips of apical teeth about equal to length of mandibular columns, which are short, stout and paral- lel....................................................................................................................................................... E. multipapilatum - Mandible with tips of apical teeth much closer together than length of mandibular columns, which are slender and diverge at apex................................................................................................................................................. E. oweni 7 Distance between tip of apical mandibular hooks either clearly much greater or much less than length of mandibular columns......................................................................................................................................................................... 8 - Distance between apical mandibular hooks apparently about same as length of mandibular columns.................................................................................................................................................................................... E. brevispiculum 8 Distance between tip apical mandibular hooks much greater than length of mandibular columns.............................. 9 - Distance between apical mandibular hooks much less than length of mandibular columns...................................... 10 9 Spicules 1–2 anal diameters (59 µm), gubernaculum a triangular plate, dorsal onchia much smaller than other two, 12 pairs of cervical setae in male, 4 in female............................................................................................ E. mawsoni - Spicules 0–75 anal diameters (34 µm), gubernaculum reduced, onchia apparently unequal, male with 12 cervical setae (female unknown)........................................................................................................................... E. pellucidum 10 Spicules 2–5 anal diameters (80 µm), gubernaculum present (37 µm) lip not striated..................... E. microdentatum - Spicules 1 anal diameter (90 µm), lip flaps striated................................................................................................... 11 11 Small species (1.5 –2.0 mm long), male head hirsute, cephalic setae maximum length 30 µm, inserted above cephalic arch, posterior rim of cephalic capsule crenelated (indistinct)................................................................... E. galeatum - Larger species (2.2–2.9 mm long), male head hirsute, cephalic setae maximum length 50 µm, longer than head diameter, inserted just below cephalic arch, posterior rim of cephalic capsule not crenelated............ E. exploratoris 12 Male head hirsute with many subcephalic and cervical setae.......................................................... E. enoploidiforme - Male head not hirsute.................................................................................................................................................. 13 13 Mandibles very long and slender, mandibular columns about twice as long as distance between apical teeth.................................................................................................................................................................. E. gorgonocephalum - Mandibles not long and slender, distance between mandibular teeth less, or only slightly longer (1.2 x), than mandibular columns...................................................................................................................................... E. georgei 14 Tail long, 4 or more anal diameters, spicules of equal length, may be annulated...................................................... 15 - Tail short, only 3 anal diameters, spicules always annulated, may be of unequal length........................................... 18 15 Spicules> 200 µm (3–3. 5 anal diameters), always annulated.................................................................................... 16 - Spicules 130–175 µm (3–3. 5 anal diameters) long, not annulated............................................................................ 19 16 Larger species, males and females more than 4 mm long, α value 27–34, onchia nearly reaching cephalic arch, inner cephalic setae long, 40 µm.......................................................................................................................................... 17 - Smaller species, 2.9–3.1 mm long, α value 117 – 19, onchia small, not reaching cephalic arch, inner cephalic setae very short, 28 µm....................................................................................................................................... E. durapelle 17 Tail setae numerous (> 10 setae)................................................................................................................. E. buetschlii - Tail setae sparse(only two medial setae)................................................................................................... E. stekhoveni 18 Spicules of unequal......................................................................................................................................... E. nadjae - Spicules equal in length............................................................................................................................... E. saveljevi 19 Head blunt anteriorly, mandibular columns parallel, diverging strongly at apex, male supplement 90 µm in front of anus................................................................................................................................................... E. brevispiculosum - Head pointed anteriorly, mandibular columns parallel, male supplement 132–158 µm in front of anus...................................................................................................................................................................................... E. polysetosum

Epacanthion agubernaculus sp. nov. Material studied: One male. Type material: Holotype MNRJ 329. Station 53 (Figure 1). Type locality: Southern part of Campos Basin (Rio de Janeiro, Brazil) at 1950 m depth, in silt-clay sediments. Etymology. The Latin " agubernaculus " refers to the absence of a gubernaculum (a = without + gubernaculus = gubernaculum). Description (Holotype). (Figs 2 and 3) Cylindrical body (L= 2045.2 µm) tapering towards both extremities. Smooth cuticle. Cephalic capsule strongly sclerotized (43.2 µm). Sensilla arranged in two circles (6 + 10): six inner labial setae (10.8 µm), six outer labial setae (31.7 µm) and four cephalic setae (11.4 µm) in the second row. The second circle is inserted slightly above the base of the cephalic capsule (3.6 µm apart). Several setae of varying lengths present in the cervical region. Somatic setae (35.4 µm) on the body, with no distinct pattern. High lips composed of three strongly sclerotized mandibles (20.4 µm long and 4 µm wide) of two longitudinal solid bars united by a thin membrane, mandibles curved in the base of the buccal cavity where three equal teeth are found (4.8 µm long and 20.4 µm wide), one dorsal and two ventrosublateral. One gland present in the base of each tooth. Amphideal fovea indistinct. Pharynx strongly muscular (516 µm long), corresponding to 87.6 % of the anterior region. Nerve ring (55.13 µm) located forward of the middle portion of the pharynx (178.5 µm) and occupying 67.3 % of the corresponding body diameter. Cardia triangular. Reproductive system diorchic, testes located at the left of the intestine (in tandem), extending to the anterior region of the body, anterior testis 233.5 µm long and posterior testis 171.1 µm long. Spicules long (186 µm), transversely striated, with four points of sclerotizations concentrated in the proximal portion and in the middle of the spicules. The distance between the sclerotization points ranged from 79 µm to 121 µm. Gubernaculum absent. One tubular precloacal supplement, finely sclerotized (18 µm long and 1.8 µm wide) and placed near the proximal region of the spicules, 104.4 µm distant from the cloaca. Tail conico–cylindrical (139.2 µm long). Three pairs of setae (range 3.6–13.8 µm long) in the conical portion, no setae in the cylindrical tail region. Caudal glands not observed. L= 2045.2; a= 25.18; b= 3.9; c= 14.6; c’= 2.7

Thoracostomopsidae Filipjev, 1927 Enoplolaiminae De Coninck, 1965 Epacanthion Wieser, 1953 Diagnosis of Thoracostomopsidae (according to Smol & Coomans 2006). Lips high. Only dorsolateral orthometanemes with robust scapulus but no caudal filament. Inner labial sensilla robust and setiform (papilliform only in Fenestrolaimus Filipjev, 1927), outer labial and cephalic setae robust and long. Epidermal glands with particularly well-differentiated outlet. Inner layer of cuticle forms a gland with particularly welldifferentiated outlet. Inner layer of cuticule forms a cephalic capsule on to which pharyngeal muscles are attached. Cephalic organs often present and of variable shape. Amphids small and situated posterior to the cephalic capsule or absent. Spacious buccal cavity with three mandibles and three teeth (onedorsal and two ventrosublateral) or with one long eversible spear. Female reproductive system didelphic���amphidelphic with antidromously reflexed ovaries (a single posterior ovary in Mesacanthion monhystera Gerlach, 1967). Caudal glands penetrate into the precaudal region. Diagnosis of Epacanthion Wieser, 1953 [according to Smol & Coomans (2006)]. Enoplolaiminae. Cuticle usually smooth. Head broadly wedge- or cone-shaped. Lips high, mostly striated. Inner labial setae long and inserted at the base of lip flaps; outer labial and cephalic setae situated at middle or anterior end of cephalic capsule. Cervical setae often present, can be numerous in males, and are sexually dimorphic. Mandibles consist of two plate���shaped columns separated by a thin sheet of cuticle (space between columns not solid) and only connected anteriorly by a bar (an intermediate stage between Enoploides and Mesacanthion); mandibular teeth small with gland which opens at tip. Pharynx relatively long and cylindrical; cardia pyriform. Females didelphic���amphidelphic with reflexed ovaries at left side of the intestine. Males diorchic with both testes at left side of the intestine; gubernaculum without apophyses present or absent. Spicules mostly long (��� 2.5 anal diameters long) or short; gubernaculum without apophysis present or absent. Preanal supplement present or absent. Three caudal glands, cells pre-caudally. Tail narrowly conical or attenuated. According to Greenslade & Nicholas (1991), there are 21 valid species: �� Epacanthion brevispiculosum Mawson, 1958 �� Epacanthion brevispiculum Mawson, 1956 �� Epacanthion b��tschlii (Southern, 1914) �� Epacanthion durapelle (Kreis, 1929) �� Epacanthion enoploidiforme (Gerlach, 1953) �� Epacanthion exploratoris Greenslade & Nicholas, 1991 �� Epacanthion flagellicaudum Gerlach, 1956 �� Epacanthion galeatum Boucher, 1977 �� Epacanthion georgei Inglis, 1971 �� Epacanthion gorgonocephalum Warwick, 1970 �� Epacanthion mawsoni Warwick, 1977 �� Epacanthion microdentatum Wieser, 1953 �� Epacanthion multipapillatum (Wieser 1959) �� Epacanthion murmanicum (Ssaweljev, 1912) �� Epacanthion nadjae Sergeeva, 1974 �� Epacanthion oliffi Inglis, 1966 �� Epacanthion oweni Keppner, 1986 �� Epacanthion pellucidum (Ssawejev, 1912) �� Epacanthion polysetosum (Jensen, 1986) �� Epacanthion saveljevi (Filipjev, 1927) �� Epacanthion stekhoveni Greenslade & Nicholas, 1991, Published as part of Guilherme, Bet��nia Cristina, Silva, Maria Cristina Da & Esteves, Andr�� Morgado, 2009, Description of a new species of Epacanthion (Thoracostomopsidae, Nematoda) from Brazil and a modified key for species identification *, pp. 99-108 in Zootaxa 2096 on pages 100-101, DOI: 10.5281/zenodo.187747, {"references":["Filipjev, I. (1927) Les Nematodes libres des mers setentrionales appartenant a la famille des Enoplidae. Archiv fur Naturgeschichte, 91 (6), 1 - 216.","De Coninck, L. A. (1965) Classe des Nematodes - Systematique des Nematodes et sous-classe des Adenophorea. In: Grasse, P (ed.) Traite de Zoologie. Masson, Paris 4, 586 - 681.","Smol N. & Coomans, A. (2006) Order Enoplida In Eyualem-Abebe, W. Traunspurger, and I. Andrassy (Eds), Freshwater Nematodes, Ecology and Taxonomy. CABI Publishing, Wallingford, Oxfordshire, pp 225 - 292.","Gerlach, S. A. (1967) Freilebende Meeres-Nematodem Von den Sarso-Inseln (Rotes Meer) Beitrag der Arbeitsgruppe Litoralforschung Meteor Forschungsergebnbisse, 2, 19 - 43.","Greenslade, P. & Nicholas, W. L. (1991) Some Thoracostomopsidae (Nematoda: Enoplida) from Australia, including Descriptions of Two Genera and Diagnostic Keys. Invertebrate Taxonomy, 4, 1031 - 52.","Mawson, P. M. (1958) Free-living Nematodes. Section 2: Additional Enoploidea from Antarctic stations. Reports of the British, Australian and New Zealand Antartic Research Expedition, (B) 6, 291 - 305.","Mawson, P. M. (1956). Free-living nematodes. Section I: Enoploidea from Antarctic stations. Reports of the British, Australian and New Zealand Antartic Research Expedition, (B) 6, 37 - 74.","Southern, R. (1914) Nemathelmia, Kinorhyncha and Chaetognatha (Clare Island survey, part 54). Proceedings of the Royal Irish Academy, 31, 1 - 80.","Kreis, H. (1929) Freilebende marine Nematoden von der Nordwestkuste Frankreichs (Trebeurden: Cotes du Nord). Capita Zoologica, 2 (7), 1 - 98.","Gerlach, S. A. (1953) Die Nematodenbesiedlung des Sandstrandes und des Kustengrundwassers an der italienischen Kuste. I. Systematischer Teil. Archivio Zoologico Italiano ʹ 37, 517 - 640.","Gerlach, S. A. (1956) Neue nematoden aus dem Kustengrundwasser des Golfes de Gascogne (Biskaya). Vie et Milieu, 6 (3), 426 - 34.","Boucher, G. (1977) Nematodes des sable fins infralittoraux de la Pierre Noire (Manche occidentale). IV. Enoplida. Bulletin du Museum National d´Histoire Naturelle, Zoologie, 325, 733 - 52.","Inglis, W. G. (1971) Marine Enoplida (Nematoda) from the coast of Western Australia. Records of the coast of Western Australia. Records of the South Australian Museum 16 (5), 1 - 13.","Warwick, R. M. (1970) Fourteen new species of freeliving marine nematodes from the Exe estuary. Bulletin of the British Museum Natural History (Zoology), 19, 137 - 77.","Warwick, R. M. (1977) The structure and seasonal fluctuations of phytal marine Nematoda associations of the Isles of Scilly. In: Biology of Benthic Organisms. Proceddings of 11 th European Marine Biology Symposium. Oxford, Pergamon Press. pp. 577 - 585.","Wieser, W. (1959) Free-living Nematodes and other Small Invertebrates of Puget Sound Beaches. University of Washington Press, Seattle, 179 pp.","Ssaweljev, S. (1912) Zur Kenntnis der Freilebenden Nematoden des Kolafjords und des Relictensees. Trudy Imperatorckago S-Peterbourbskago Obschestva Estestvoispitaltelei, 43, 73 - 126.","Sergeeva, N. G. (1974) New free-living nematodes (Enoplida) from the Black Sea. 2. Zoologicheskii Zheitschrift, 53 (1), 120 - 124.","Inglis, W. G. (1966) Marine nematodes from Durban, South Africa. Bulletin of the British Museum of Natural History (Zoology), 14, 81 - 106.","Keppner, E. J. (1986) New species of free - living marine nematodes (Nematoda: Enoplida) from Bay County, Florida, U. S. A. Transactions of the Amercian Microscopical Society, 105 (4), 319 - 37","Jensen, P. (1986) The nematode fauna in the sulphide-rich brine seep and adjacent bottoms of the East Flower Garden NW. Gulf of Mexico. III. Enoplida. Zoologia Scripta, 15 (2), 93 - 99."]}

Chromaspirina guanabarensis sp. n. Figs 1 and 2 Type specimens: all in the Museu Nacional do Rio de Janeiro: holotype male (MNRJ 305), two paratype males (MNRJ 307), allotype female (MNRJ 306), two paratype females (MNRJ 308) and three paratype juveniles (MNRJ 309). Type locality: Bica Beach (22 ° 49 ’37.9’’S and 43 ° 11 ’15.9’’W), Guanabara Bay, Rio de Janeiro, Brazil, collected on 08/06/ 2000 by Dr. André Esteves. Sediment of very coarse to coarse sand with median grain size ranging from 2850 µm to 570 µm; intertidal zone. Etymology: The species name refers to the type locality. Measurements: Table 1. -: not applicable or not seen. Male. Body long and relatively slender. Head blunt, rounded. Tail conical. Cuticle with fine transverse striations starting posterior to the anterior edge of amphidial fovea and without ornamentation. Minute somatic setae arranged in eight longitudinal rows extending from the pharyngeal region to tail region. Head region smooth, with six inner and six outer labial papillae, and four cephalic setae 4–5 µm long, located just anterior to the anteriormost striation of the body cuticle. Amphidial fovea a ventrally wound spiral, largely surrounded by striations; its diameter 29–39 % of corresponding body diameter. Buccal cavity large with an acute dorsal tooth and two smaller ventrosublateral teeth. Pharynx anteriorly cylindrical, posteriorly widened to a pyriform bulb. Nerve ring located at about mid-pharynx length. Cardia triangular in cross section, surrounded by intestine. Tail conical with three caudal glands dorsally located, extending up to the cloaca and opening at the tail tip through a spinneret. Terminal part of tail smooth, 26–28 % of the total tail length. Reproductive system monorchic with anterior outstretched testis on right side of the intestine. Testis with narrow short germinal zone. Sperm cells round (16–21 µm diameter). Spicules equal, slender, ventrally curved with thick sclerotized lamina and hook-shaped capitulum; thin velum present. Gubernaculum slightly arcuate, trough-shaped, without apophysis. No obvious precloacal supplements present, but equally spaced short ventral setae which could be interpreted as supplements. Female. Similar to male except for a cylindrical cardia, a shorter smooth tail portion (17–24 % of tail length). Reproductive system didelphic-amphidelphic with reflexed ovaries; anterior ovary to the left of intestine, posterior ovary to the right of intestine. Anterior genital branch shorter than posterior. Vulva a simple transverse slit. One large egg (78–82 µm long and 38–44 µm wide) present in each uterus. Juvenile. Only second stage juveniles observed; this stage is characterized by its small body size and small primordium, not clearly observed. External morphology similar to the adults. Diagnosis. Chromaspirina guanabarensis sp. n. is characterized by its large size (> 2mm); the position of the cephalic setae at the posterior edge of the smooth head region, and the conical tail shape in both sexes. The non-striated part of the tail is shorter in females than in males. Males are characterized by spicules shaped with hooked sclerotized capitula and well sclerotized lamina, together with absence of precloacal supplements but presence of short setiform precloacal sensilla. Differential diagnosis. Chromaspirina guanabarensis sp. n. most closely resembles C. okemwai Muthumbi, Verschelde & Vincx, 1995 in having similar dorsal tooth and spicule shape, but differs in having a more evenly tapering tail and more pronounced labial papillae (C. okemwai has a tail with a wide anterior part narrowing posteriorly and minute labial sensilla only visible with SEM). Discussion. The species included in the genus Chromaspirina have changed frequently. We consider the genus to have twenty valid species (including the new species). There are two species inquirendae, eight species transferred back to their original genus, and two species transferred to another genus. C. robusta Wieser, 1954 and C. paucispira Stekhoven, 1950, known from two juveniles and one female respectively, were regarded as species inquirendae by Wieser & Hopper (1967). The genus Bolbolaimus was synonymized with Chromaspirina by Luc & De Conninck (1959) but re-established as a valid genus by Jensen (1978), based mainly on the female reproductive system with outstretched ovaries, stoma and pharynx structure and cuticle ornamentation. Jensen re-established C. denticulata (Gerlach, 1953), C. pellucida (Cobb, 1920) and C. punctata (Cobb, 1920) within Bolbolaimus when rejecting synonymy of this genus with Chromaspirina; and regarded two other species C. amabilis ( De Man, 1922) and C. cobbi (Chitwood, 1938) as species inqueridae of Bolbolaimus. C. dimorpha (Hopper, 1961), C. inflexa (Wieser, 1951) and C. rabosa (Gerlach, 1956) have been transferred back to their original genus Desmodora mainly because of the amphidial fovea not being surrounded by striations of the body cuticle (Wieser & Hopper, 1967). Among the Chromaspirina species, the amphideal fovea is partially or totally surrounded by striations, e. g. C. pellita and C. parma, respectively. However, one exception occurs in the genus: C. dubia possesses striations restricted to the posterior quarter of the body, but other characteristics, such as a large dorsal tooth and a pyriform bulb support its presence within the genus Chromaspirina. C. longisetosa Jensen, 1985 was transferred to the genus Bolbolaimus by Muthumbi et al. (1995) and C. spinulosa Wieser, 1959 was transferred to the genus Metadesmodora by Gerlach (1963), but Blome (1982) proposed the new combination Echinodesmodora spinulosa when he erected the genus Echinodesmodora. C. inaurita is added to the list of valid Chromaspirina species; however it was not recorded by Muthumbi et al. (1995). C. inaurita possesses several characters (e.g. large stoma, pyriform pharyngeal bulb) indicating affinities with Chromaspirina, although it also shows some characteristics of the genus Spirinia, e.g. a small dorsal tooth. Within the genus Chromaspirina the dorsal tooth may be variable in size, so this character is insufficient to place the species outside Chromaspirina. C. modesta is regarded as valid because the work of Bussau (1993) conforms to the code for zoological nomenclature is a valid publication, and has been recognised world-wide as a reference among the scientific community of marine nematodes researchers. C. pontica and C. inglisi differ from each other only by the presence of fine hairs over the body in the latter. Warwick (1970) suggested that the hair-like ornamentations may be either easily overlooked or considered as epigrowths of unicellular cyanophyceous algae, and if so the species are the same. Muthumbi et al. (1995) describing C. okemwai also found some fine hair-like structures attached to the cuticle of their specimens, but when the organisms were sonicated and viewed by SEM, the tail region of some animals appeared devoid of the “hairs”. The hair-like structures were also present on pre-moult phase of the newly made cuticle (Muthumbi et al., 1995). Therefore, the origin of these structures remains doubtful. We regard C. pontica and C. inglisi as valid species, but consider that the hypothesis of C. inglisi being a junior synonym of C. pontica should not be completely disregarded though further investigation is needed. Four species in the genus have a smaller dorsal tooth when compared with the remaining 16 species. This emphasises the close relationship of this genus with Spirinia as suggested by Wieser & Hopper (1967). Further investigation is needed into the relationships Spirinia with Chromaspirina. Chromaspirina guanabarensis sp. n. belongs to the group of species characterized by a poorly developed dorsal tooth. Within this group, the new species is easily discriminated by the absence of sexual dimorphism in the amphidial fovea, distinct labial sensilla and tail shape.

Key to species of Syringolaimus 1 Tail end filiform............................................................................................................................................................ 2 - Tail end not filiform.................................................................................................................................................... 10 2 Spicules narrow....................................................................................................................................... S. filicaudatus - Spicules wide................................................................................................................................................................ 3 3 Tail with setae.................................................................................................................................................. S. ingens - Tail without setae.......................................................................................................................................................... 4 4 Odontia divided............................................................................................................................................................. 5 - Odontia entire................................................................................................................................... S. striatocaudatus 5 Labial sensilla absent.................................................................................................................................. S. marisalbi - Labial sensilla present................................................................................................................................................... 6 6 Cephalic sensilla absent......................................................................................................................... S. taniae sp. n. - Cephalic sensilla present............................................................................................................................................... 7 7 Cephalic sensilla setaceous........................................................................................................................ S. renaudae - Cephalic sensilla papilla shaped................................................................................................................................... 8 8 Cuticule striations difficult to resolve..................................................................................................... S. annae sp. n. - Cuticule striations well defined along the body............................................................................................................ 9 9 Tail long “c” S. gladiatus - Tail short “c”> 6, with spinneret.................................................................................................................... S. nitidus 10 Labial sensilla absent................................................................................................................................ S. smarigdus - Labial sensilla present................................................................................................................................................. 11 11 Cephalic sensilla absent....................................................................................................................... S. magdae sp. n. - Cephalic sensilla present............................................................................................................................................. 12 12 Tail conical.......................................................................................................................................................... S. loofi - Tail conical-cylindrical............................................................................................................................................... 13 13 Tail without setae.................................................................................................................................. S. smolae sp. n. - Tail with setae.............................................................................................................................................. S. venustus, Published as part of Lima, Rita De Cássia Coelho, Lins, Lidia, Silva, Maria Cristina Da & Esteves, André Morgado, 2009, Four new species of Syringolaimus De Man, 1888 (Nematoda: Ironidae) from the Southeast Atlantic (Brazil), with redefinition of valid species and the proposal of a new key *, pp. 119-136 in Zootaxa 2096 on pages 134-135

Syringolaimus smolae sp. n. (Figs. 5 and 6) Type material: One male and one female collected from Stations 74 and 85 (Appendix). Holotype ♂ 1: slide number MNRJ 333 station 74; allotype ♀ 1 slide number MNRJ 334 station 85. Type locality: Campos Basin (Rio de Janeiro, Brazil). Holotype ♂ 1 found at 750 m depth in silt-clay sediments, layer between 0–2 centimeters. Allotype ♀ 1: found at 1350 m depth in silt-clay sediments, vertical profile: between 2–5 centimeters. Etymology. The specific epithet honors Nicole Smol, Coordinator of the Nematology course at Ghent University, Belgium. Description. Measurements: Holotype ♂ 1: L: 1036.5; hd: 7.8; amph wid: 3.6; cbd: 13.2; amph (%): 27.3; amph dist: 7.2; buc cav l: 37.2; ph: 175.5; buc cav 1/ph (%): 21.2; nr/ph (%): 51.3; ex pore/ph (%): 51.3; bulb l: 35.4; bulb l/ph (%): 20.2; bulb d: 18.6; cbd: 24; bulb(%): 77.5; mbd: 22.8; abd: 21; t: 112.2; con/t (%): 44.9; cil/t%: 55.1; spin: 6; spin/t (%): 5.3; spic: 28.2; gub: 13.8; a: 45.4; b: 5.9; c: 9.9; c’: 5.3. Allotype ♀ 1: L: 992; hd: 9.0; amph wid: 3.6; cbd: 10.8; amph %: 33.3; amph dist: 7.8; buc cav l: 33; ph: 158.4; buc cav 1/ph (%): 20.8; nr/ph (%): not visible; ex pore/ph (%): 41.7; bulb l: 30.6; bulb l/ph/ (%): 19.6; bulb d: 13.2; cbd: 17.1; bulb (%): 77.2; mbd: 17.4; abd: 13.8; t: 115.8; con/t (%): 42; cil/t (%): 58; spin: 6.0; spin/t (%): 5.1; a: 57; b: 6.3; c: 8.6; c’: 8.4. Male Holotype: Body 1036.5 µm long, maximum body diameter 22.8 µm. Cuticle faintly striated. Six outer labial papillae and four cephalic papillae. Amphideal phovea occupying 27.3% of corresponding body diameter. Head diameter 7.8 µm. Cylindrical, sclerotized, buccal cavity, weakly involved by pharynx muscles, 37.2 µm long, 21.2% of pharynx length. Three bifid teeth of equal size, one dorsal and two subventral. Delicate pharynx with an oval basal bulb, 35.4 µm long and 18.6 µm wide, corresponding to 77.5% of body diameter and 20.2% of total pharynx length. Secretory-excretory pore and nerve ring at same level, situated 51.3% from anterior end. Rounded cardia. Single testis lying on right side of intestine, with glandular part splitting duct into regions of cells of varying degrees of maturity. Short deferent duct with sperm cells in beginning of duct. One precloacal papilla present. Spicule setiform, vellum present. Gubernaculum triangular. Conical-cylindrical tail with spinneret (6 µm), corresponding to 5.3% of tail length. Cylindrical region corresponding to 55.1% of tail length. Three caudal glands present. Female Allotype: Body slender, amphidelphic-didelphic, with reflexed ovaries located ventrally to intestine. Vulva situated at 57% of total body length, with two glands on each side of vulva. Diagnosis. Syringolaimus smolae sp. n. is characterized by the setiform spicule, the triangular gubernaculum, the position of the secretory-excretory pore at the same level of the nerve ring, and the presence of two glands located posterior and anterior to the vulva. Relationships. S. smolae sp. n. resembles S. loofi Gourbault & Vincx, 1985; both species share the presence of inner labial papillae, bifid teeth, and precloacal papillae; the equal value of De Man ratios b and c; and the proportion of the small spinneret in relation to the total tail length. However, the secretory-excretory pore in S. smolae sp. n. is situated in the middle region of the pharynx, whereas in S. loofi the pore is situated at the base of the buccal cavity. Other differences observed are the spicule, gubernaculum, and the tail shapes (conical in S. loofi and conical-cylindrical in S. smolae sp. n.). The female of the new species possesses two glands, one on each side of the vulva. The presence of a glandular portion in the testis is not observed in S. loofi., Published as part of Lima, Rita De Cássia Coelho, Lins, Lidia, Silva, Maria Cristina Da & Esteves, André Morgado, 2009, Four new species of Syringolaimus De Man, 1888 (Nematoda: Ironidae) from the Southeast Atlantic (Brazil), with redefinition of valid species and the proposal of a new key *, pp. 119-136 in Zootaxa 2096 on pages 128-130, {"references":["Gourbault, N., & Vincx, M. (1985) Deux especes nouvelles d'Ironidae marins; observations sur les spermatozoides flagelles des Nematodes. Bulletin Musee National Histoire Natural, section A, 1, 109 - 118."]}

Sabatieria bitumen sp. nov. (Figure 6 and 7) Description Studied material: 6 males; 5 females. Type material: Male holotype MNRJ 309; Female allotype MNRJ 310; Five male paratypes 54–58 NM LMZOO­UFPE; Four female paratypes 59–62 NM LMZOOUFPE. Type locality: Campos Basin (Rio de Janeiro, Pernambuco, Brazil), found at 750 and 1650 meters depth in silt­clay sediments. Measurements: see table 4. HOLOTYPE PARATYPE ALLOTYPE PARATYPE ...... continued on the next page Etymology: The specific name bitumen means oleum. It is named in honour to the Brazilian Petroleum Company (PETROBRAS). Male: Cylindrical body. Punctated cuticle with transversal rows of dots and lateral differentiation of larger dots, easily visible on tail region. Attenuated head. Six inner labial setae, six outer labial setae and four cephalic setae. Buccal cavity is small and cup­shaped. Somatic setae short. Amphidial fovea spiral with two turns and a half and occupying 78 % of the corresponding body diameter. Pharynx clavate gradually expanding towards the posterior end, but without distinct bulb. Cardia short and small. Nerve ring slender located at the middle of pharynx, anterior to secretory­excretory pore. Ventral gland between the terminal region of the pharynx and the beginning of the intestine. Reproductive system composed by two opposed and outstretched testes, the anterior on the left and the posterior one on the right of the intestine. Spicules curved and paired with distal part hook­like, proximal end with a septum almost up to ½ of the spicule. This median rib divides the spicule into dorsal and ventral halves. There are several glandular cells located around the spicules. Gubernaculum short with a narrow dorsal apophysis. The spermatozoa are elongated. Eight pore­shaped precloacal supplements and a precloacal setae are present. Tail conical and short with 3 caudal glands endimg in a spinneret. Two caudal setae. Female: Females similar to males. Amphidial fovea spiral with three turns occupying 66 % of the corresponding body diameter. Buccal cavity cup­shaped. Pharynx cylindrical, gradually expanding towards the posterior end, but without distinct bulb. Cardia short and small. Nerve ring slender located at the middle of pharynx and anterior to secretory­excretory pore. Ventral gland between the end of pharynx and the beginning of intestine. Reproductive system didelphic­amphidelphic with ovaries outstretched and relatively short. Vulva at midbody, similar to S. spiculata (figure 2 C). Tail conical and short. Three caudal glands ending in a spinneret and two terminal setae. Diagnosis This species is characterized by the presence of lateral differentiation with larger equally distributed dots in rows; head diameter 11–12 µm ɗ; hook­like projection in distal portion of spicule; 6–10 pore­like precloacal supplements. Relationships Sabatieria bitumen resembles S. conicauda Vitiello, 1970 in body and tail shape, as well as morphometric values and the De Man’s index. However, Sabatieria bitumen may be distinguished from S. conicauda in relation to spicule length (S. conicauda = 36–37 µm and S. bitumen = 40–47 µm) and projection of the distal portion of it. This new species resembles S. praedatrix de Man, 1907 and S. flecha Pastor de Ward, 2003 in the projection present in the distal half of the spicule, can be differenciated in the shape, arrow­like in S. praedatrix and S. flecha and hook­like S. bitumen. S. lepida Vitiello, 1976 has a triangular ventral projection in the distal part of spicules and S.bitumen has a hook­like projection. Moreover, tail is conical in S. bitumen and conico­cylindrical in S. praedatrx, S.lepida and S. flecha.

Sabatieria subrotundicauda sp. nov. (Figure 8 and 9) Description Studied material: 3 males; 6 females. Type material: Male holotype MNRJ 311; Female allotype MNRJ 312; Two male paratypes 63–64 NM LMZOO­UFPE; Five female paratypes 65–69 NM LMZOOUFPE. Type locality: Campos Basin (Rio de Janeiro, Pernambuco, Brazil): deep­sea found in 750 m depth, siltclay sediments. Measurements: see table 5. TABLE 5. Measurements (μm) of Sabatieria subrotundicauda sp. nov. Etymology: The specific name subrotundicauda refers to the tail shape which is almost rounded. Male: Body cylindrical. Punctated cuticle with transversal dotted lines, more evident in tail region. Lateral differentiation present, being punctations larger and more widely spaced. Somatic setae very short. Head rounded and attenuated. Six inner labial setae, six outer labial setae short and four cephalic setae very short. Amphidial fovea spiral with two and a half turns. Buccal cavity cup­shaped. Pharynx clavate, gradually expanding towards the posterior end, but without distinct bulb. Cardia short and small. Nerve ring slender located at the middle of pharynx and anterior to secretory­excretory pore. Ventral gland is located between the end of pharynx and the beginning of intestine. The reproductive system possesses two opposed and outstretched testes anterior one on the left and posterior one on the right side of the intestine. Four pairs of ejaculatory glands are present. Spicules paired, ventrally curved and with a projection like an arrow in the distal part; proximal end with a septum. There are several glandular cells located around the spicules. Gubernaculum small with a narrow apophisis. Seven pore­shaped precloacal supplements are present. Tail short and rounded. It presents a slightly narrow region at 2 / 3 of the tail. Three caudal glands are present ending in a spinneret. Two caudal setae very short. Female: Females are similar to males. Internal labial and external labial papilliform. Cephalic setae short. Amphidial fovea spiral with two turns and a half. Somatic setae very short. Buccal cavity cup­shaped. Pharynx clavate, gradually expanding towards the posterior end, but without distinct bulb. Cardia short, small and pearshaped. Nerve ring slender located at the middle of pharynx and anterior to secretory­excretory pore. Ventral gland situated between the end of pharynx and the beginning of intestine. The reproductive system composed by two opposed and reflexed ovaries. Vulva present at mid­body. Tail short and rounded. Three caudal glands.Two caudal setae very short. Relationships Sabatieria subrotundicauda resembles Sabatieria conicauda, possessing the same body shape and conical tail. The measurements in Sabatieria subrotundicauda are higher than in S. conicauda e.g. length, cephalic setae length and spicule (L = 948–1051 µm ɗ; 1153 µm Ψ; Cs = 2.3–2.6 µm; spic= 36–37 µm ). Females of S. conicauda have ovaries outstretched. Among Sabatieria species with rounded tail or similar to S. conicauda, the presence of reflexed ovaries was observed only in the S. dorylaimopsoides but the last species differs in the presence of a thorn not discernible in Sabatieria subrotundicauda. S. lepida Vitiello, 1976 has a triangular ventral projection in the distal part of spicules and S. subrotundicauda has a hook­like projection. Tail is conical in S. subrotundicauda and conico­cylindrical in S.lepida. S. subrotundicauda resembles to S. rotundicauda Allgén 1959 in the rounded tail. The difference is in the length (L= 3115 µm) and the female have extended gonads.

Sabatieria paraspiculata sp.nov. (Figure 4 and 5) Description Studied material: 1 holotype male; 1 allotype female. Type material: Male holotype MNRJ 307; Female allotype: MNRJ 308. Type locality: Campos Basin (Rio de Janeiro, Pernambuco, Brazil), 1050 and 1650 m depth, silt­clay sediments. Measurements: see table 3. TABLE 3. Measurements (μm) of Sabatieria paraspiculata sp. nov. Etymology: The specific name paraspiculata refers to the similarity with S. spiculata: greek para = similar; spiculata = S. spiculata. Male: Body cylindrical. Punctated cuticle with transversal rows of dots and lateral differentiation of larger and wider spaced dots. Head rounded and attenuated, with six minute internal labial papilliform sensilla, six external minute labial setae and four short cephalic setae. Buccal cavity small and cup­shaped. Amphidial fovea spiral with three turns and occupying 77 % of the corresponding body diameter. Pharynx clavate anteriorly surrounding posterior part of stoma then gradually expanding towards the posterior end, but without distinct bulb. Nerve ring and secretory­excretory pore located at the middle of pharynx. Cardia small and pearshaped. Ventral gland situated posterior to the pharynx. Reproductive system diorchic, testes opposed and outstretched; anterior testis on the left and posterior one on the right of the intestine. Four pairs of ejaculatory glands anterior to spicules.Curved spicules with proximal part containing septum; Gubernaculum short, with a narrow dorsal apophysis. There are several glandular cells located around the spicules. Seven minutes poreshaped precloacal supplements. Tail short and stout, with 3 caudal glands ending in a spinneret. Female: Females largely similar to the male, but longer. Six internal labial sensilla, six external labial setae and four short cephalic setae. Amphidial fovea spiral with three turns occupying 50 % of the corresponding body. Buccal cavity small and cup­shaped. Clavate pharynx, gradually expanding posteriorly but without basal bulb. Nerve ring surrounding pharynx located at the middle of pharynx. Cardia small. Ventral gland located posteriorly to the pharynx. Reproductive system didelphic­amphidelphic, with two relatively short outstretched ovaries. Vulva at 46 % of the total body length from anterior end, and possesses the similar cuticularized structure wich is present in S. spiculata (figure 2 F). Tail short and stout with three caudal glands ending in a spinneret. Diagnosis S. paraspiculata sp.nov. is characterised by the combination of length and maximum diameter, de Man’s index a (L= 1080 ɗ 1540 Ψ; M = 51 ɗ 74 Ψ; a = 21 ɗ Ψ). Stout tail; seven minutes precloacal supplements pore­shaped. Female with relatively short outstretched ovaries. Relationships Sabatieria paraspiculata sp.nov. is similar to S. spiculata sp.nov. by the general body shape, conical tail and spicule shape. It may be distinguished from S.spiculata by the presence of teeth; length of tail 94 µm ɗ 90 µm Ψ; head diameter 15 µm ɗ 20 µm Ψ; c`index 2 ɗ 1,9 Ψ. S. paraspiculata sp.nov. resembles S.conicauda Vitiello 1970 and S. dorylaimopsoides Allgén 1959 in of the shape of head, conical tail, spicule shape and type of supplements. Can be distinguished from S.conicauda by the length of spicule (spic = 36–37 µm) and c´index 2.1–2.5. Differs from S. dorylaimopsoides by the presence of a thorn in the buccal cavity and the with reflexed ovaries in female.

Sabatieria spiculata sp.nov. (figure 2 and 3) Description Studied material: 6 male; 4 female Type material: Male hollotype MNRJ 305; female allotype MNRJ 306; 5 males 46–50 NM LMZOO­ UFPE; Three females 51–53 NM LMZOOUFPE. Type locality: Campos Basin (Rio de Janeiro, Pernambuco, Brazil). It was found at 750 and 1650 meters depth, in silt­clay sediments. Measurements: see table 2. Etymology: The specific name spiculata refers to the long and sligth spicule. Male: Cylindrical body, medium­sized, tail short with cylindro­conical shape. Punctated cuticle with transversal rows of dots and lateral differentiation with larger and wider spaced punctations, specially in the tail region. Rounded and attenuated head with anterior sensilla arranged in three crowns: six minute internal labial sensilla, six external labial setae and four cephalic setae. Somatic setae, short.. Amphidial fovea spiral, with three turns. Buccal cavity cup­shaped, with diminute dorsal teeth. Pharynx clavate, gradually expanding towards to the posterior end, but without distinct bulb. Cardia short, pear shaped. Nerve ring slender located at the middle of pharynx and anterior to secretory­excretory pore. Ventral gland opposite posterior end of pharynx and beginning of intestine; system diorchic; opposed and outstretched testes. Anterior testis situated on the left of the intestine and the posterior one on the right side. Spicule paired with the same length equally wide and slightly curved ventrally; proximal half with mid­septum (each spicule has inside the core sensilla). Several glandular cells are arranged around the spicules. Small gubernaculum with narrow apophysis. Minute porelike precolacal supplements and precloacal setae. Spermatozoa oval, elongated, showing some striation. Conical tail with three caudal glands, ending in a spinneret. Two caudal setae. TABLE 2. Measurements (µm) of Sabatieria spiculata sp.nov. Female: Females are quite similar to males, although some minor morphological differences are observed. Total body length and head diameter similar to males. Amphidial fovea spiral with three turns. Buccal cavity cupshaped with minute dorsal tooth. Pharynx clavate. Nerve ring situated at the middle of pharynx. Secretoryexcretory pore somewhat more posterior than in male. Reproductive system didelphic­amphidelphic, with outstretched ovaries. Egg proximal to vagina in the anterior part of uterus. Vulva at mid­body. Vagina thinwalled; pars proximalis vaginae (= vagina uterina) surrounded by a constrictor muscle. Dilators vaginae extending from the uterus wall opposite the vagina towards the subdorsal body wall. Finely granular vaginal glands present at the pars distalis vaginae (figure 2 C). Tail conical with three caudal glands ending in a spinneret. Posterior end of tail with two short somatic setae. Diagnosis S. spiculata sp.nov. is characterised by a minute dorsal tooth; 10–14 pore­like precloacal supplements; narrow spicules with 53–62 µm; tail conical (70–94 µm). Relationships S. spiculata sp.nov. resembles S.conicauda Vitiello 1970 and S. dorylaimopsoides Allgén 1959 in the shape of head, tail, spicule and supplements. Can be distinguished from S.conicauda by the total lenght (L= 1051–1153 ɗ and 1153 Ψ), number of supplements (7–8) and non armed buccal cavity. Difers from S.dorylaimopsoides by the thorn in buccal cavity and the reproductive system in female with reflexed ovaries.

Submitted by Alberto Vieira (martins_vieira@ibest.com.br) on 2018-01-12T16:09:59Z No. of bitstreams: 1 552188.pdf: 13006169 bytes, checksum: 8bf2dc666edb41bf9ed601e7ecf7af4c (MD5) Made available in DSpace on 2018-01-12T16:10:00Z (GMT). No. of bitstreams: 1 552188.pdf: 13006169 bytes, checksum: 8bf2dc666edb41bf9ed601e7ecf7af4c (MD5) Previous issue date: 2002 Determina a composição genérica, a estrutura trófica e a estrutura da comunidade de nematódeos marinhos da planície de maré de Coroa Grande, Baía de Sepetiba, Rio de Janeiro, Brasil (22º 55' 00"S e 43º05' 30"W). Amostras mensais foram coletadas durante a baixa-mar, usando-se um amostrador de 1cm², no período de maio/1998 a abril/1999. As amostras foram obtidas em perfis com estratos que representaram os diferentes níveis da zona entre-marés. Também. coletaram-se amostras para determinar a composição granulométrica, o teor de matéria orgânica e a concentração de clorofila a. A análise canônica de correspondência foi utilizada para avaliar a estrutura da comunidade. Duas diferentes classificações foram utilizadas para determinar a estrutura trófica da comunidade. Um total de 31 gêneros foi encontrado: Anoplostoma, Bathylainnus, Comesoma, Daptonema, Enoplolainnus, Eurystomina, Halichoanolaimus, Haliplectus, Metachromadora, Oxystomina, Oncholainnus, Paracanthonchus, Paraodontophora, Sabatieria, Steineria, Sphaerolaimus, Spirinia, Terschellingia, Theristus, Viscosia e Trissonchulus. Os gêneros Chromadorella, Chromaspirinia, Dorylaimopsis, Euchromadora, Gomphionema, Gammanema, Linhomoeus e Paramonohystera apresentaram o seu primeiro registro de ocorrência para a costa brasileira. A composição faunística não foi diferente de outros hábitats similares. A análise canônica de correspondência mostrou uma estrutura espaço-temporal da comunidade de nematódeos, com as amostras dos níveis inferiores da planície de maré (próximos a zona infralitoral) formando um grupo separado das amostras dos níveis superiores. Os padrões de diversidade mostram-se influenciados pelas características sedimentológicas do ambiente, especialmente, a quantidade de finos. Os valores de diversidade encontrados para a área de estudo são semelhantes aos de outros estudos realizados em áreas tropicais, no entanto, são mais baixos quando comparados aos valores obtidos em áreas temperadas. Os padrões gerais da estrutura trófica da comunidade estão associados às variações na abundância dos três principais gêneros: Comesoma, Daptonema e Oncholaimus. Em termos espaciais, os comedores de depósito stricto sensu são dominantes nos níveis inferiores da planície de maré, enquanto os predadores facultativos predominam nos níveis superiores. Determine the generic composition, trophic structure and community structure of marine nematodes on the Coroa Grande tidal flat, Sepetiba bay, Rio de Janeiro. Brazil (22º55'00"S e 43º05' 30''W). Monthly samples were taken during Iow tides, using a corer with 1cm², from may-98 to april-99. Samples were obtained within transect strata which represent the different levels of the intertidal zone. Samples for granulometric composition, organic matter anel chlorophyll analysis were also collected. Canonical correspondence analysis (CCA) was used to evaluate the community structure. Two different classifications were used in order to determine the trophic structure. The structure of nematode community showed a spatial-temporal. with samples of the lower tidal flat level (near to the subtidal zone) forming a separate group from samples of the upper levels. A total of 31 genera were found: Anoplostoma, Bathylainnus, Comesoma, Daptonema, Enoplolainnus, Eurystomina, Halichoanolaimus, Haliplectus, Metachromadora, Oxystomina, Oncholainnus, Paracanthonchus, Paraodontophora, Sabatieria, Steineria, Sphaerolaimus, Spirinia, Terschellingia, Theristus, Viscosia and Trissonchulus. The genera Chromadorella, Chromaspirinia, Dorylaimopsis, Euchromadora, Gomphionema, Gammanema, Linhomoeus and Paramonohystera were recorded for the first time in Brazilian sediments. The faunal composition was not very different from other similar habitats. Diversity patterns were influenced by the sedimentological characteristics of the environment, especially, the amount of fine sediments. Diversity values found on the studied arca were similar to those of different studies in tropical areas; nevertheless are low when compared to temperate areas. The general patterns of lhe trophic structure were associated with the change in the abundance of the three main genera: Comesoma, Daptonema e Oncholaimus. In spatial terms, deposit feeders stricto sensu predominated in the lower level of the tidal flat, while facultative predators dominated the upper levels.