Ceroderma Raffray, 1890

Yin, Zi-Wei, Nomura, Shûhei & Li, Li-Zhen, 2012, Redescription of Ceroderma asperata Raffray, and description of Cerochusa cilioceps gen. et sp. n. from Hainan, South China (Coleoptera, Staphylinidae, Pselaphinae), Zootaxa 3355, pp. 62-68 : 63

Ceroderma Raffray, 1890

Ceroderma Raffray, 1890a: 112 .

Type species. Ceroderma asperata Raffray (subsequent monotypy by Raffray, 1890b: 199).

Diagnosis. Head triangular; frontal rostrum low; lacking frontal fovea; antennomeres XI elongate and conical. Pronotum transversely triangular, lacking median antebasal fovea, with punctiform lateral antebasal foveae; with lateral and antebasal spines. Elytra with three small basal foveae, lacking discal striae. Abdomen with inner and outer marginal carinae of tergite IV forming broad triangular ridge at lateral margins; tergite IV longest, not much longer than tergite V, lacking discal carinae.

Redescription. Body flat; length about 2.6. Head triangular, with frontal rostrum low, antennal tubercles moderately prominent; lacking frontal fovea; vertex largely and broadly concave; vertexal foveae small, connected by shallow and broad triangular sulcus (foveae and sulcus absent in male due to presence of sexual feature); postocular margins roundly expanded laterally; with eleven antennomeres, clubs formed by apical three antennomeres, antennomeres XI elongate and conical; ocular-mandibular carinae well-defined; eyes oval; maxillary palpi with palpomeres III small and triangular, IV gradually narrowed in basal half; small gular foveae close.

Pronotum transversely triangular; lateral antebasal foveae punctiform, lacking median antebasal foveae; with small lateral and antebasal spines; disc barely convex; basolateral foveae absent; paranotal carinae distinct; lateral procoxal foveae barely indicated. Elytra with three basal foveae, lacking discal striae, sutural and marginal striae complete. Thorax with small median and lateral mesoventral foveae; lateral mesocoxal foveae present; with lateral metaventral foveae; posterior margin narrowly notched medially. Legs with tarsomeres II and III subequal in length.

All abdominal segments lacking mediobasal impression and foveae; tergite IV with lateral margins produced as thick triangular ridge edged by inner and outer marginal carinae, ridges extending entire tergal length, lacking discal carinae; tergites VI–VII with ridges much thinner; tergite VII with indistinct lateral tubercles. Sternite IV with median carina; sternites V–VII with short triangular basolateral ridges.

Male with vertex, postocular margins and protibiae modified. Aedeagus with paramere fused to median lobe to from elongate ventral lobe; lacking obvious dorsal lobe.

Comparative notes. Placed close to Hingstoniella Jeannel from Sikkim and Tibet, and Cerochusa gen. n. from Hainan described below by sharing a flat and broad general form, the transversely triangular pronotum, and the lack of a median antebasal fovea on the pronotum. Ceroderma can be separated from Hingstoniella by having the head with postocular margins broadly expanded laterally, the pronotum with small but distinct lateral and antebasal spines, and each elytron with three basal foveae. Hingstoniella has the head with postocular margins roundly narrowed basally, the pronotum lacking any spines, and each elytron with single large basal fovea. Ceroderma differs from Cerochusa by the lack of discal carinae on tergite IV and the lack of basomedian and basolateral foveae of sternite IV. In contrast, Cerochusa has short, close discal carinae on tergite IV, and sternite IV has distinct mediobasal and two pairs of basolateral foveae.