Rhabdias ambystomae Kuzmin, Tkach and Snyder, 2001

KUZMIN, YURIY, 2013, Review of Rhabdiasidae (Nematoda) from the Holarctic, Zootaxa 3639 (1), pp. 1-76 : 30

Rhabdias ambystomae Kuzmin, Tkach and Snyder, 2001

( Fig. 13 )

Hosts: Ambystoma maculatum , A. annulatum , A. laterale ( Amphibia: Caudata : Ambystomatidae ).

Site: lungs.

Distribution: Nearctic. In the U.S.A.: states Michigan, Wisconsin and Arkansas.

Description (after Kuzmin et al. 2001, 2003). Body elongated, 10.36 (6.48–13.04) mm long, 354 (185–440) wide. Anterior end rounded, posterior end tapered. Body cuticle swollen, especially on anterior and posterior thirds of body, with irregularly arranged transverse folds. Round oral opening surrounded with 6 small lips, each bearing 1 elongated conical inner papilla. Two minute outer papillae situated on each submedian lip. Lateral lips each bearing 1 outer papilla and an amphid opening. Inner papillae directed toward oral opening. Flat cuticular ring present around oral opening. Buccal capsule cup-like in lateral view, round in apical view. Buccal capsule depth 14 (12–17), width 17 (15–20). Oesophagus 541 (450–620) long (5.3 [4.1–7.7] % of body length). Oesophagus width 43 (37–50) at anterior end, 52 (37–67) at middle of muscular region, 55 (42–67) at middle of glandular region; posterior bulb 83 (65–100) wide. Nerve ring at 185 (130–260) from anterior end of oesophagus (34.2 [22.8–46.4] % of oesophagus length). Excretory glands indistinct. Tail wide, conical, 237 (160–325) long (2.3 [1.6–3.1] % of body length). Vulva usually postequatorial, with indistinct lips. Distance from anterior end to vulva 5.78 (3.64– 7.34) mm (55.9 [47.4–60.5] % of body length). Proximal regions of both ovaries overlapping at level of vulva. Both limbs of genital system bend backward at distal part of ovaries. Anterior ovary occasionally forms 2 loops as it bends. Oviducts short. Uteri wide, thin-walled, filled with numerous eggs. Egg size 119 (112–130) × 58 (55–65).

Material studied: 42 specimens from A. maculatum (18) and A. annulatum (24). Material is stored in USNPC and SIZK.

References: Kuzmin et al. (2001, 2003).

Figures

FIGURE 13. R. ambystomae: A—anterior part of body, lateral view; B—head end, lateral view; C—head end, apical view; D—tail end, lateral view. Scale bars: A—0.1 mm; B, C—0.05 mm; D—0.2 mm.