Keys to genera

1 (10) Buccal capsule small, not wider than anterior part of oesophagus, or absent.

2 (3) Cuticular spines present on surface of body in anterior part (Fig. 1). Parasitic in Scincidae (Reptilia: Sauria) in Australia. – Pneumonema Johnston, 1916.

Fig. 1. Anterior part of P. tiliquae body, SEM

3 (2) Surface of body without spines.

4 (5) Surface of body cuticle with longitudinal crests (Fig. 2). Buccal capsule absent. Three onchia present on oesophageal apex. Parasitic in mouth cavity of Ameiva ameiva (Reptilia: Sauria: Teiidae). – Chabirenia Lhermitte-Vallarino, Bain, Deharo et al., 2005.

Fig. 2. Cross-section through the C. cayennensis mid-body showing longitudinal crests (after Lhermitte-Vallarino et al., 2005).

5 (4) Surface of body cuticle without longitudinal crests.

6 (7) Body cuticle inflated, at least on some parts of body (Fig. 3). Buccal capsule present, in some species consisting of anterior and posterior segments. Parasitic in amphibians (Anura, Caudata, Gymnophiona) and lizards from Iguania (Agamidae, Chamaeleonidae, Iguanidae); probably, present in some Gekkonidae. – Rhabdias Stiles et Hassall, 1905.

Fig. 3. Anterior part of R. sphaerocephala showing typical cuticular inflation in a live specimen.

7 (6) Body cuticle not inflated, just thickened in anterior and posterior parts, often transversely striated. Parasitic in snakes (Reptilia: Serpentes).

8 (9) Apical extremity with 8–10 conical projections directed anteriorly (Fig. 4) – Acanthorhabdias Pereira, 1927.

Fig. 4. Anterior end of A. acanthorhabdias (after Pereira, 1927).

9 (8) Apical extremity with 6 small, equal or sub-equal lips arranged in lateral groups (Fig. 5). Buccal capsule funnel-shaped, or absent in some species. – Serpentirhabdias Tkach, Kuzmin et Snyder, 2014.

Fig. 5. Apical extremity of S. eustreptos (SEM) showing lips arranged in lateral groups.

10 (1) Buccal capsule large, thick-walled, wider than anterior end of oesophagus.

11 (12) Six onchia present on oesophageal apex (bottom of buccal capsule) (Fig. ). Parasitic in Anguidae (Reptilia: Sauria). – Entomelas Travassos, 1930.

A      B

Fig. 6. Entomelas ophisauri: lateral view (A) and sub-apical view (B) of anterior end showing large buccal capsule and onchia.

12 (11) Onchia absent. Parasitic in Scincidae (Reptilia: Sauria).

13 (14) Apical extremity globular, with dorsal and ventral pseudolabia (Fig. ). – Neoentomelas Hasegawa, 1989.

Fig. 7. Anterior part of N. asatoi body (lateral view) showing characteristic shape of anterior end.

14 (13) Apical extremity with 6 small lips, or with 4 submedian lips and 2 lateral pseudolabia (Fig.8 ). – Kurilonema Szczerbak et Sharpilo, 1969.

Fig. 8. Apical extremity of K. browni showing submedian lips and lateral pseudolabia.