Keratodegnathus mirabilis, Pace, 2014

Pace, R., 2014, Aleocharinae from Sabah (Borneo) collected by Guillaume de Rougemont (Coleoptera, Staphylinidae), Linzer biologische Beiträge 46 (1), pp. 727-794 : 747-748

Keratodegnathus mirabilis nov.sp. ( Figs 29 and 135-137 )

T y p e m a t e r i a l Holotype? (Pigydium lost), Sabah, Danum Valley , B.R.L., f.i.t., 14- 16.II.2007, G. de Rougemont leg. ( CROU).

D e s c r i p t i o n: Length 3.33 mm. Body shiny, brown, mouthparts and abdomen reddish, antennae brown with the four basal antennomeres reddish, legs reddish with brown femora. Scape very long, second antennomere shorter than the scape, third longer than the second, fourth to tenth strongly transverse. Eyes longer than the postocular region in dorsal view. Body devoid of reticulation. Head impunctate. Pronotum with two discal dimples with separate external lateral punctures. Granulation of the elytra sparse, fine and very superficial. Free abdominal tergites concave and bare, posterior ¾ of the fifth free tergite with confluent longitudinal striae in the punctate anterior ¼. Vertex of the head with strong forwardly projecting protuberance which overhangs a deep and wide median concavity. A salient lamina directed towards the base of the mandible is borne at the base of each antenna. The pigydium was detached and lost in the trap collection tray.

C o m p a r a t i v e n o t e s: The new species is attributed to Keratodegnathus nov.gen. on the basis the insertion of the antennae behind the level of the front of the eyes ( Fig. 135 ), and the horned mandibles. The new species differs from Keratodegnathus rougemonti nov.sp. in its very transverse intermediary antennomeres and in the pronotum with two discal foveae edged by some punctures. Moreover the

horns of the mandibles are borne in a vertical position ( Fig. 136 ), whereas in Keratodegnathus rougemonti nov.sp. the horns are borne laterally ( Fig. 131 ).

E t y m o l o g y: The new species is named "marvelous" in reference to its mandibular horns.

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 135-145: Head in dorsal, lateral and frontal view, aedeagus in lateral and ventral view. (135- 137): Keratodegnathus mirabilis nov.gen., nov.sp.; (138-139): Myrmecopella borneensis nov.sp.; (140-141): Orphnebius acutus nov.sp.; (142-143): Orphnebius ocularis nov.sp.; (144-145): Orphnebius acutissimus nov.sp. Scale bars: 0.1 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.