Keratodegnathus, Pace, 2014

Pace, R., 2014, Aleocharinae from Sabah (Borneo) collected by Guillaume de Rougemont (Coleoptera, Staphylinidae), Linzer biologische Beiträge 46 (1), pp. 727-794 : 746-747

Keratodegnathus nov.gen. ( Figs 27-28 and 128-134 )

D i a g n o s i s: The new genus resembles to Orphnebius MOTSCHULSKY, 1857 in the form of the pronotum, but the antennae are inserted behind the level of the front of the eyes and the mandibles of the male and the female bear horns at the base ( Fig. 131 ). The spermatheca ( Fig. 130 ) is clearly different from those of known species of Orphnebius .

D e s c r i p t i o n: In facies very similar to Orphnebius MOTSCHULSKY, 1857 and Strabocephalium BERNHAUER, 1911 . Temples not bordered below. Head broad. Neck about a third as broad as the head. Gular sutures parallel. Antennae inserted behind the level of the front of the eyes. Mandibles short, stout, curved and pointed, with more or less strongly developed horns inserted near their base in both sexes but less developed in the female. Maxillary palpi with the 1 st joint small, 2 nd slightly curved and slightly thickened towards apex, 3 rd as long as the 2 nd but a good deal thicker at the apex, 4 th subulate, nearly half as long as the 3 rd. Outer lobe of maxilla rather narrow, extending beyond the apex of the inner lobe, ciliate at apex; inner lobe narrow, pointed, with several fine curved spines below the apex, ciliate elsewhere ( Fig. 133 ). Mentum transverse, the sides dilated behind, narrowed towards the front, the anterior margin truncate ( Fig.134 ). Labial palpi short, 3-jointed, the 1 st joint short, 2 nd shorter and narrower, 3 rd narrower than the 2 nd and a little longer than the 1 st. Tongue short and broad, subtriangular, scarcely as long as the 1 st joint of the labial palpi, with a narrow triangular excision reaching nearly to the base and dividing it into two triangular lobes rounded at the apices, with apical setae, ( Fig.132 ). Paraglossae feeble, extending to the base of the 1 st joint of the labial palpi. The pronotal epipleurae visible from the side, pronotum without a median sulcus. Mesosternal process broad, truncate behind, extending about half the length of the coxae, the coxae widely separated. Elytra not emarginate postero-laterally. Abdomen more or less navicular, only the 1 st visible segment transversely impressed at the base. Legs long. Tibiae ciliate. Tarsal formula: 4, 5, 5; posterior tarsi with the 1 st joint long, a little longer than the 2 nd and 3 rd together.

T y p u s g e n e r i s Keratodegnathus rougemonti nov.sp.

E t y m o l o g y: The masculine name of the new genus means "horned mandible" from the ancient Greek κέρατωδης = horned and γνάθος = jaw.

Figures

Figs 25-33: Habitus. (25): Tetrabothrus femoralis nov.sp., scale bar 5.9 mm; (26): Strabocephalium borneorum nov.sp., scale bar 5.9 mm; (27): Keratodegnathus rougemonti nov.sp. male, scale bar 5.9 mm; (28): Keratodegnathus rougemonti nov.sp. female, scale bar 5.5 mm; (29): Keratodegnathus mirabilis nov.sp., scale bar 3.3 mm; (30): Myrmecopella borneensis nov.sp., scale bar 3.4 mm; (31): Orphnebius acutus nov.sp., scale bar 3.6 mm; (32): Orphnebius ocularis nov.sp., scale bar 2.7 mm; (33): Orphnebius acutissimus nov.sp., scale bar 3.6 mm.

Figs 126-134: Aedeagus in lateral and ventral view, sixth free urotergum of male, spermatheca, head in lateral view, labium with labial palpus, maxilla with maxillary palpus, mentum. (126-127): Strabocephalium borneorum nov.sp.; (128-134): Keratodegnathus rougemonti nov.gen., nov.sp. Scale bars: 0.1 mm.