taxonID	type	description	language	source
03EB87BE5842FF8FFDB1FE73C11EFCAA.taxon	type_taxon	Type species Tobrilus gracilis (Bastian, 1865) = Trilobus gracilis Bastian, 1865. Diagnosis (after Andrássy 2007; Holovachov & Shoshin 2014) Body 1.0 – 4.5 µm long. Cuticle smooth or very finely annulated. Buccal cavity cup-or funnel-shaped, with overlapping subventral pocket and teeth close to each other. Vagina moderately strong. Spicules comparatively short. Supplements 3 to 13, mostly six, small, non-echinate, but with a small central thorn, submerged, not protruding. Spacing between supplements nearly equal.	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
03EB87BE5842FF8BFD56FC11C4D1FA89.taxon	description	Figs 1 – 2, Table 1 (morphometric)	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
03EB87BE5842FF8BFD56FC11C4D1FA89.taxon	diagnosis	Diagnosis Tobrilus elginus sp. nov. is characterized by a 2200 – 2995 µm long body; cuticle smooth under light microscope; crystalloids absent; inner labial sensillae papilliform; six outer labial sensillae in the shape of smooth non-articulated setae 14 – 17 µm long, 45 – 57 % for males and 44 – 59 % for females of labial region width; four cephalic sensillae on the shape of thin and smooth setae 6 – 8 µm long; buccal cavity spacious, funnel-shaped; dorsal pocket and its tooth absent; both subventral pockets overlapping adjacent to each other. Spicules comparatively thick, slightly curved, short, 50 – 53 µm long, 1.1 – 1.3 long as the cloacal body diameter; gubernaculum in the shape of ‘ gutter’; precloacal supplements 6 in number, small, submerged; tail slender, long, elongate-conical, with terminal seta.	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
03EB87BE5842FF8BFD56FC11C4D1FA89.taxon	materials_examined	Type material Holotype RUSSIA • ♂; Lake Baikal (Maloye More Strait), Elginsky Bay; 53 ° 09 ′ 14 ″ N, 107 ° 10 ′ 26 ″ E; 30 cm depth; 16 Jul. 2018; sand; HM RAS slide reference number 102 / 69. Paratypes RUSSIA • 2 ♂♂, 1 ♀; same collection data as for holotype; HM RAS slide reference number 102 / 69 (1507 - 1, 1507 - 3, 1507 - 5) • 7 ♂♂, 13 ♀♀; same collection data as for holotype; LIN-SB.	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
03EB87BE5842FF8BFD56FC11C4D1FA89.taxon	etymology	Etymology The specific epithet means ‘ from Elga’, the type locality name.	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
03EB87BE5842FF8BFD56FC11C4D1FA89.taxon	description	Description Male Body comparatively long and thin. Cuticle smooth under light microscope, 1.5 – 2.0 µm thick. Body diameter at the posterior pharynx end 1.7 – 2.0 times the width of the labial region. Crystalloids absent. Somatic setae rare and short, 5 – 7 µm long. Labial region slightly offset from the adjacent body; lips well developed. Six inner labial sensillae papilliform. Six outer labial sensillae in the shape of smooth, non-articulated setae 14 – 17 µm long, 45 – 57 % of labial region width. Four cephalic sensillae in the shape of thin and smooth setae, 6 – 8 µm long. Both circles of setae drawn close together. Cheilostom of the average size. Buccal cavity spacious, funnel-shaped, with thick walls. Dorsal pocket and its tooth absent. Both subventral pockets overlapping adjacent to each other. Its teeth small, close to each other (~ 5 µm away). Stoma 1.1 – 1.3 times as long as labial region width. Amphidial fovea cup-shaped, opening at the level of buccal cavity. Pharynx muscular, comparatively long, expanding gradually along entire length. Cardiac glands large, rounded, 20 – 23 µm in diameter. Ventral gland, its canal, ampulla and excretory pore not seen. Testes paired, opposed, situated to the left of intestine; anterior testes outstretched, posterior testis reflexed. Vas deferens well developed. Spicules thick, slightly curved, short, 1.1 – 1.3 times as long as the cloacal body diameter, apically bifurcate. Gubernaculum in the shape of ‘ gutter’, 42 – 53 % of the spicule length. Precloacal supplements 6 in number, small, submerged. Supplement ampulla flattened, contents concentrated at ampulla base. Supplement cap absent. Central thorn protruding slightly above cuticle. Supplements approximately identical in size and situated about equidistant from each other. The closest to cloaca supplement at 21 – 30 µm away from it; supplement row 355 – 435 µm long. Tail slender, elongate-conical, with terminal seta 6 – 8 µm long. Caudal glands well developed; spinneret in the shape of a short, conical tube. Female General morphology similar to that of males in structure of cuticle and anterior body end. Cardia small, surrounded by three round glands. Prerectum not observed. Rectum length equal to or slightly greater than anal body diameter. Reproductive system didelphic, amphidelphic. Ovaries situated to the left of intestine, reflexed and comparatively short. Oocytes numerous. Vulva a transverse slit and situated slightly posterior to mid-body. Vulval lips not sclerotized and not protruding outside the body contour. Cuticular wrinkles around vulva and vulva glands not seen. Vagina short, with thick walls. Uterus containing numerous spermatozoa and 1 – 2 eggs, measuring 65 – 105 × 26 – 50 µm. Tail slender, long, elongate-conical, with terminal seta. Caudal glands well developed.	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
03EB87BE5842FF8BFD56FC11C4D1FA89.taxon	discussion	Remarks Tobrilus elginus sp. nov. is most similar to T. amabilis and T. bekmanae. The new species differs from the first species in the shorter body (♂ L = 2.2 – 2.8 mm, ♀ L = 2.2 – 2.9 mm vs ♂ L = 2.8 – 3.0 mm, ♀ L = 3.0 – 3.1 mm in T. amabilis), shorter spicules (50 – 53 µm long vs 55 – 58 µm long in T. amabilis), longer gubernaculum (20 – 26 µm long vs 16 – 17 µm long in T. amabilis), shorter supplement row (355 – 435 µm long vs 487 µm long in T. amabilis) (Tsalolikhin 1974). Tobrilus elginus sp. nov. differs from T. bekmanae in the shorter body (♂ L = 2.2 – 2.8 mm, ♀ L = 2.2 – 2.9 mm vs ♂ L = 2.6 – 3.1 mm, ♀ L = 2.9 – 3.8 mm in T. bekmanae), thinner body (♂ a = 39 – 56, ♀ a = 37 – 46 vs ♂ a = 25 – 40, ♀ a = 28 – 35 in T. bekmanae), shorter tail (♂ c = 14.2 – 18.7, c ʹ = 3.3 – 4.4, ♀ c = 11.0 – 13.4, c ʹ = 5.0 – 6.9 vs ♂ c = 8.5 – 13.7, c ʹ = 6, ♀ c = 7.4 – 10.0, c ʹ = 9 in T. bekmanae), a more posterior vulva (V = 57 – 64 % vs V = 41 – 50 % in T. bekmanae), shorter supplement row (355 – 435 µm long vs 334 µm long in T. bekmanae) (Tsalolikhin 1975).	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
03EB87BE5846FF84FD40FA3FC75FFD8C.taxon	description	Figs 3 – 4, Table 2 (morphometric)	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
03EB87BE5846FF84FD40FA3FC75FFD8C.taxon	diagnosis	Diagnosis Tobrilus juliae sp. nov. is characterized by a 1800 – 2386 µm long body; cuticle smooth under light microscope; crystalloids absent; inner labial sensillae papilliform; six outer labial sensillae in the shape of smooth, non-articulated setae 4 – 6 µm long for males (24 – 35 % of labial region width) and 5 – 6 µm long for females (28 – 38 % of labial region width); four cephalic sensillae on the shape of thin and smooth setae 3 – 4 µm long for males and 2 – 4 µm long for females; buccal cavity spacious, barrelshaped; dorsal pocket and it tooth absent; both subventral pockets overlapping adjacent to each other. Spicules slightly curved, 45 – 50 µm long, 1.2 – 1.5 long as the cloacal body diameter; gubernaculum in the shape of ‘ gutter’; precloacal supplements 6 – 7 in number, small, submerged; tail short, elongateconical, with terminal seta.	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
03EB87BE5846FF84FD40FA3FC75FFD8C.taxon	materials_examined	Type material Holotype RUSSIA • ♂; Lake Baikal (Southern basin), near Cape Berezovy; 51 ° 30 ′ 11 ″ N, 104 ° 32 ′ 33 ″ E; 5 m depth; 6 Sep. 2016; bodies of dead sponges Lubomirskia baicalensis collected by divers; HM RAS slide reference number 102 / 70. Paratypes RUSSIA • 9 ♂♂, 10 ♀♀; same collection data as for holotype; LIN-SB; 1 ♀; same collection data as for holotype; HM RAS slide reference number 102 / 70 (1390 - 1).	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
03EB87BE5846FF84FD40FA3FC75FFD8C.taxon	etymology	Etymology The species named in gratitude to Ms Julia Zvereva.	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
03EB87BE5846FF84FD40FA3FC75FFD8C.taxon	description	Description Male Body comparatively long and thin. Cuticle smooth under light microscope, 1.0 – 1.5 µm thick. Body diameter at the posterior pharynx end 2.1 – 2.5 times the width of the labial region. Crystalloids absent. Somatic setae rare and short, 3 – 4 µm long. Labial region only slightly offset from the adjacent body; lips well developed. Six inner labial sensillae papilliform. Six outer labial sensillae in the shape of smooth, non-articulated setae 4 – 6 µm long, 24 – 35 % of labial region width. Four cephalic sensillae in the shape of thin and smooth setae 3 – 4 µm long. Both circles of setae drawn close together. Cheilostoma of the average size. Buccal cavity spacious, barrel-shaped, with thick walls. Dorsal pocket and it tooth absent. Both subventral pockets overlapping adjacent to each other. Its teeth small, close to each other (distance ~ 3 µm). Stoma 1.0 – 1.2 as long as labial region width. Amphidial fovea cup-shaped, opening at the level of buccal cavity. Pharynx muscular, comparatively long, expending gradually along entire length. Cardiac glands large, rounded, 15 – 17 µm in diameter. Ventral gland, its canal, ampulla and excretory pore not seen. Testes paired, opposed, situated to the left of intestine; anterior testis outstretched, posterior testis reflexed. Vas deferens well developed. Spicules slightly curved, comparatively short, 1.2 – 1.5 times as long as the cloacal body diameter, apically bifurcate. Gubernaculum in the shape of ‘ gutter’, 43 – 47 % of the spicule length. Precloacal supplements 6 – 7 in number, small, submerged. Supplement ampulla flattened, its contents concentrated at ampulla base. Supplement cap absent. Central thorn protruding slightly above cuticle. Supplements approximately identical in size and situated about equidistant from each other. The closest to cloaca supplement at 11 – 20 µm away from it; supplement row 175 – 290 µm long. Tail short, elongate-conical, with terminal seta 3 – 5 µm long. Caudal glands well developed; spinneret in the shape of a short, conical tube. Female General morphology similar to that of males in structure of cuticle and anterior body end. Six outer labial sensillae in the shape of smooth setae 5 – 6 µm long, 28 – 38 % of labial region width; four cephalic sensillae in the shape of thin, smooth setae 2 – 4 µm long. Cardia small, surrounded by three round glands. Rectum length equal to or slightly greater than anal body diameter. Reproductive system didelphic, amphidelphic. Ovaries situated to the left of intestine, reflexed and comparatively short. Oocytes numerous. Vulva a transverse slit and situated slightly posterior to mid-body. Vulval lips not sclerotized and not protruding outside the body contour. Cuticular wrinkles around vulva and vulva glands not observed. Vagina short. Uterus containing numerous spermatozoa and 1 – 2 eggs, measuring 70 – 72 × 40 – 43 µm. Tail short, elongate-conical, with subterminal seta. Caudal glands well developed.	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
03EB87BE5846FF84FD40FA3FC75FFD8C.taxon	discussion	Remarks Tobrilus juliae sp. nov. is most similar to T. securus and T. saprophagus in body size. From the first species it differs in the thinner body (a = 41 – 63 vs a = 25 – 40 in T. securus), shorter tail (c = 11.3 – 23.4, c ʹ = 2.4 – 6.1 vs c = 6.7 – 8.4, c ʹ = 6.3 – 9.3 in T. securus), comparatively shorter outer labial setae (24 – 35 % of labial region width vs 40 – 45 % of labial region width in T. securus) and shorter spicules (45 – 50 µm long vs 52 – 58 µm long in T. securus) (Gagarin & Naumova 2011). From the second species T. juliae sp. nov. differs in the thinner body (a = 41 – 63 vs a = 30 – 43 in T. saprophagus), shorter tail in males (♂ c = 17.5 – 23.4 vs ♂ c = 11.5 – 16.7 in T. saprophagus) and shorter outer labial setae (4 – 7 µm long, 24 – 35 % labial region width vs 10 – 12 µm long, 37 – 46 % of labial region width in T. saprophagus (Naumova & Gagarin 2017).	en	Naumova, Tatyana V., Gagarin, Vladimir G. (2019): Two new nematode species of the genus Tobrilus Andrássy, 1959 (Nematoda, Triplonchida) from Lake Baikal, Russia. European Journal of Taxonomy 579: 1-13, DOI: 10.5852/ejt.2019.579
