Cerochusa Yin and Nomura

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 : 66-67

Cerochusa Yin and Nomura , new genus

Type species. Cerochusa cilioceps , new species

Diagnosis. Head nearly triangular; lacking frontal rostrum; lacking frontal fovea; antennomeres XI robust and conical. Pronotum transversely triangular, deeply incised at level of punctiform lateral antebasal foveae; lacking median antebasal fovea; with large lateral and antebasal spines. Elytra with two basal foveae, discal striae shallow and short. Abdomen with inner and outer marginal carinae of tergite IV–VI forming broad triangular ridge at lateral margins; tergite IV longest, about twice length of tergite V; discal carinae present.

Description. Body flat and broad; length about 2.4. Head triangular, lacking frontal rostrum, antennal tubercles indistinct; lacking frontal fovea; vertex slightly convex medially, vertexal foveae well-defined, connected by U-shaped sulcus, with short median carina (carina indistinct in male due to presence of sexual feature); postocular margins angularly expanded laterally; posterior margin triangularly impressed medially; with eleven antennomeres, clubs weakly formed by apical three antennomeres, antennomeres XI robust 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 distinct median and lateral sulci and discal carinae; with large lateral and antebasal spines; lateral margins largely incised at level of antebasal foveae; disc slightly convex; basolateral foveae absent; paranotal carinae distinct, with additional pair of lateral carinae; lateral procoxal foveae present. Elytra with two basal foveae, discal striae weakly indicated; sutural and marginal striae extending to elytral apex; lacking subhumeral foveae. Thorax with small median and lateral mesoventral foveae; lateral mesocoxal foveae present; with lateral metaventral foveae; posterior margin narrowly notched medially. Legs with tarsomeres thickened, tarsomeres II and III subequal in length.

Abdomen with lateral margins of tergite IV–VI produced as thick triangular ridge edged by inner and outer marginal carinae, ridges extending entire tergal length; tergite IV with large lateral foveae; discal carinae short and close, reaching one-fifth tergal length; tergites V–VII lacking mediobasal impression and foveae. Sternite IV with distinct median and two pairs of lateral foveae, short lateral carinae present; sternites V–VII lacking foveae.

Male with vertex and mesotibiae modified. Aedeagus with paramere fused to median lobe to from elongate ventral lobe; with membranous dorsal lobe.

Comparative notes. Most close to Ceroderma in having a flat and broad body form, the triangular head lacking a frontal fovea and with medially concaved posterior margin, the presence of pronotal lateral and antebasal spines and the lack of a median antebasal fovea on the pronotum. Cerochusa can be separated by the elytra with two basal foveae and shallow discal striae, the presence of short discal carinae on tergite IV, that tergite being twice length of tergite V, and the presence of mediobasal and basolateral foveae on sternite IV. While Ceroderma has three basal elytral foveae, the elytra lacks discal striae, tergite IV lacks discal carinae and is slightly longer than tergite V, and sternite IV lacks any foveae. Hingstoniella shares with Cerochusa the presence of two basal elytral foveae, and tergite IV being twice as long as tergite V, but the roundly narrowed postocular margins, the smooth pronotal lateral margins and the lack of discal carinae on tergite IV quickly separate Hingstoniella from Cerochusa .

Etymology. The generic name is a combination of ‘ cer ’ (horn), and ‘- chusa ’ (with), referring to the strongly spinose pronotal lateral margins. The species name is formed by ‘ cil ’ (hair) and ‘ ceps ’ (head), with respect to the male sexual character on the head.