Rhabdias sp.

KUZMIN, YURIY, 2013, Review of Rhabdiasidae (Nematoda) from the Holarctic, Zootaxa 3639 (1), pp. 1-76 : 57-58

Rhabdias sp.

( Fig. 30 )

Host: Elaphe quadrivirgata ( Reptilia: Serpentes: Colubridae ).

Site: lungs.

Distribution: Eastern Palaearctic (Kunashir Island).

Description. Body comparatively small. Body length 2.68–2.8 mm, maximum width 166–174. Body cuticle thin, transversely striated. Buccal capsule cup-like or almost cylindrical, 8–10 deep and 20–22 wide. Oesophagus club-shaped, 266–290 long (9.9–10.6 % of body length). Width of oesophageal posterior bulb 54–58. Nerve ring at 108–116 from anterior end of oesophagus (38.2–43.7 % of oesophagus length). Excretory pore situated at the level of posterior edge of nerve ring. Intestine wide, thick-walled. Vulva situated at 1.14–1.22 mm from anterior end (42.7–43.5 % of total length). Uteri short, sac-like. Eggs in uteri containing larvae. Tail conical, elongated, 174– 199 long (6.3–7.1 % of body length). Tail end tapered.

Remark. The specimens studied differed from R. kurilensis from the same host and locality by the transversely striated cuticle, shape of buccal capsule, position of excretory pore and presence of larvae in eggs. However, the shortage of material does not allow the description of new species.

Material studied: 3 specimens ( SIZK) .

2.3. Genus Entomelas Travassos, 1930

Synonym: Angiostoma Dujardin, 1845 (part.).

Type species: Entomelas entomelas ( Dujardin, 1845) Travassos, 1930 .

2.3.1. Diagnosis

Buccal capsule wide, thick-walled, barrel-shaped or hemispherical in lateral view, round in apical view. Six teeth (onchia) present on the bottom of buccal capsule (on the anterior end of oesophagus). Each sector of oesophagus bearing a pair of teeth. Three teeth may be partially reduced in some species. Six cephalic lips arranged in two lateral groups. Lateral lips small, conical, rounded. Submedian lips flattened, with dense, arc-shaped inner edges. Cephalic papillae minute.

Adult hermaphrodites parasitic in lungs, body cavity or pharynx of lizards from the families Anguidae and Agamidae in Europe, Central Asia, Ceylon, southern North America and Central America.

Four known species occur in Palaearctic.

2.3.2. Key to Palaearctic species

1 All teeth equal in shape and size. Buccal capsule width exceeding 60 micrometers. Body cuticle thin, smooth or transversely striated............................................................................................ 2.

- Three of 6 teeth partially reduced. Buccal capsule width not exceeding 45 micrometers. Body cuticle swollen, its outer surface covered with irregular folds............................................................................ 3.

2 Circular cuticular fold present on the head end behind the cephalic lips ( Fig. 31 A ). Teeth small, situated close to entrance to oesophageal lumen. Tail end sharply pointed. Parasite of Anguis fragilis ..... E. entomelas ( Dujardin, 1845) Travassos, 1930 .

- Head end lacking annular cuticular fold. Teeth comparatively large, situated closer to buccal capsule walls ( Fig. 33 ). Tail end rounded. Parasite of Pseudopus apodus ............................................... E. ophisauri ( Kreis, 1940) .

3 Tail end with short apical cuticular needle ( Fig. 31 H ). Parasite of Anguis fragilis ............. E. dujardini (Maupas, 1916) .

- Tail conical, tail end tapered, lacking apical cuticular needle ( Fig. 32 C, F ). Parasite of Pseudopus apodus .................................................................................. E. kazachstanica Sharpilo et Vakker, 1972 .

2.3.3. Descriptions of species

Figures

FIGURE 30. Rhabdias sp. A—general view; B—head end, lateral view; C—anterior part of body, lateral view; D—tail end, lateral view. Scale bars: A—0.5 mm; B—0.05 mm; C, D—0.2 mm.

FIGURE 31. A—E. entomelas, head end, lateral view; B—E. entomelas, tail end, lateral view; C—E. entomelas, head end, apical view; D—E. entomelas, anterior part of body, lateral view; E—E. dujardini, anterior part of body, lateral view; F—E. dujardini, head end, lateral view; G—E. dujardini, head end, apical view; H—E. dujardini, tail end, lateral view. Scale bars: A...D, H—0.1 mm; E—0.2 mm; F—0.05 mm; G—0.025 mm.

FIGURE 32. E. kazachstanica. Gravid: A—anterior part of body, lateral view; B—head end, lateral view; C—tail end, lateral view. Subgravid: D—head end, lateral view; E—anterior part of body, lateral view; F—tail end, lateral view; G—genital system, lateral view. Scale bars: A, E, G—0.2 mm; B, D—0.05 mm; C, F—0.1 mm.

FIGURE 33. E. ophisauri. Gravid: A—head end, lateral view; B—anterior part of body, lateral view; C—tail end, lateral view. Subgravid: D—head end, lateral view; E—vulva and proximal part of anterior syngonium, lateral view; F—bend of posterior genital tube with oviduct; G—tail, lateral view. Scale bars: A, C...G—0.1 mm; B—0.5 mm.