Entomelas ophisauri ( Kreis, 1940 )

KUZMIN, YURIY, 2013, Review of Rhabdiasidae (Nematoda) from the Holarctic, Zootaxa 3639 (1), pp. 1-76 : 61-64

Entomelas ophisauri ( Kreis, 1940)

( Fig. 33 )

Synonyms: Hexadontophorus ophisauri Kreis, 1940 ; Entomelas entomelas ( Dujardin, 1845) sensu Baker (1980) (part.).

Host: Pseudopus apodus ( Reptilia: Sauria : Anguidae ).

Site: lungs, body cavity.

Distribution: Western and, partially, Central Palaearctic (south-eastern Europe, Caucasus, West of Central Asia).

Description. Head end truncate, tail end tapering. Body length 7.94 (6.37–9.82) mm, maximum width 199 (150–284). Body cuticle thin, smooth or transversely striated. Buccal capsule wide, with narrower basal part, 52 (46–64) deep and 75 (64–84) of maximum width. Teeth comparatively large, equal in shape and size, situated closer to buccal capsule walls. Oesophagus club-shaped, 0.95 (0.75–1.15) mm long (12.1 [8.4–15.4] % of body length). Bulb 125 (106–148) wide. Nerve ring at 242 (219–284) from anterior end of oesophagus (25.4 [20.0–30.6] % of oesophagus length). Excretory pore situated close to level of posterior edge of nerve ring. Intestine wide in specimens from lungs, comparatively narrower in specimens from body cavity. Vulva at 4.44 (3.47–5.52) mm from anterior end (56.0 (50.4–61.3) % of body length). Vulva lips reduced. Uteri elongated. In specimens from lungs uteri containing numerous (more than 100) eggs with fully developed larvae. In specimens from body cavity eggs less numerous or absent. Posterior genital tube bending three times in region of oviduct (observed in subadult specimens). Proximal parts of ovaries overlapping at level of vulva. Tail elongated, gradually tapering, 419 (348– 527) long (5.3 [4.1–6.7] % of body length). Tail end rounded. Tail curved dorsally in specimens fixed with cold fixatives.

Biology. Life cycle is of rhabdiasoid type. Free-living females contain up to 16 eggs in uteri. Up to 8 larvae develop inside each female. Infective larvae were able to infect terrestrial snails Deroceras sp. and Arion sp. ( Kuzmin and Sharpilo 2000). Subadult specimens were observed in lungs and body cavity of experimentally infected host. Adult specimens from the body cavity are usually enclosed into thin-walled capsules. Arrest of migrating specimens in the body cavity depends presumably on the intensity of lung infection by both E. ophisauri and E. kazachstanica individuals.

Remarks. Baker (1980) considered this species to be a form of E. entomelas associated with specific host ( Pseudopus apodus ). Our studies on the development of both species proved the validity of E. ophisauri . Molecular data ( Kuzmin and Tkach 2009) also supported the validity of the species. On the other hand, E. ophisauri is obviously related to other species of the genus Entomelas . That is why we support synonymisation of the genus Hexadontophorus Kreis, 1940 with Entomelas Travassos, 1930 proposed by Baker (1980).

Material studied: 56 specimens ( SIZK), 39 from body cavity and 17 from lungs, from various localities .

References: Kreis (1940), Sharpilo (1976), Baker (1980), Kuzmin and Sharpilo (2000)

2.4. Genus Kurilonema Szczerbak et Sharpilo, 1969

Synonym: Entomelas Travassos, 1930 sensu Baker, 1980 (part.).

Type species: K. markovi Szczerbak et Sharpilo, 1969 .

Diagnosis. Body small, head end truncate, tail end tapering. Body cuticle inflated in anterior part, the thickness of cuticle gradually decreasing posteriorly. Buccal capsule large, almost spherical. Six small lips, or 4 lips and 2 lateral pseudolabia present. Oral opening round. Teeth absent. Uteri short, tubular.

Adult hermaphrodites parasitic in lungs of lizards from the family Scincidae in eastern and south-eastern Asia.

Figures

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.