Baeocera incurva, Löbl, 2022

Löbl, Ivan, 2022, Supplement to the knowledge of the Scaphidiinae (Coleoptera: Staphylinidae) of the Moluccas, Revue suisse de Zoologie 129 (1), pp. 103-118 : 104-106

Baeocera incurva sp. nov.

Figs 4-6

Materiel examined: Holotype; MHNG; male; MALUK: Kai Besar , Bombay, G. Dab , 3.IX.81, D. Agosti F911019 .

Paratypes; MHNG; 1 male, 2 ex. with the same data as the holotype . – MHNG; 2 males, 1 female; MALUK: Kai Besar , G. Tukrau nr. Bombay , 300-400 m, 7.IX.81 D. Agosti, F91075 .

Etymology: The species epithet is a Latin adjective meaning bent.

Diagnosis: The species is defined by the following characters in combination: Body-length about 1.25- 1.35 mm, body blackish with lighter apical abdominal segments; lateral margins of pronotum and elytra nearly continuously arcuate; pronotum finely punctate; elytron entirely coarsely punctate, lacking basal stria, sutural stria shortened, starting posterior of level of scutellum; hypomeron very finely punctate; mesepimeron, mesanepisterum, metaventrite and ventrite I distinctly punctate; ventrite I without basal wrinkles or striae; aedeagus symmetrical, with apical process in lateral view abruptly narrowed near apex, parameres sinuate, nearly evenly broad and bent dorsally in lateral view, internal sac with complex sclerites, as in Fig. 6 , lacking membranous scale or denticle-like structures.

Description: Length 1.25-1.33 mm, width 0.85- 0.88 mm. Head and most of body blackish, apical abdominal segments, femora and tibiae reddish-brown, tarsi and antennae yellowish. Head with interocular distance slightly larger than dorsoventral eye diameter. Antennomere II slightly longer than antennomere III. Length/width ratios of antennomeres as: III 24/6: IV 22/6: V 30/7: VI 30/7: VII 37/9: VIII 33/8: IX 41/12: X 41/14: XI 46/15. Pronotum and elytra nearly continuously arcuate. Pronotum not microsculptured, pronotal punctation hardly visible at 50 times magnification; lateral carinae of pronotum concealed in dorsal view. Point of scutellum exposed. Elytra nearly entirely covering abdomen. Elytron weakly narrowed apically, with lateral margin rounded; lateral margin carinae concealed in dorsal view, adsutural area flat and narrow; sutural stria punctate, shortened, starting well posterior of level of tip of scutellum; basal stria absent; lateral stria punctate. Elytral disc not microsculptured, with punctation well delimited, much coarser than on pronotum, nearly regular, puncture intervals mostly about as to three times puncture diameters. Hind wings fully developed. Impressed inferior part of hypomeron with few very fine punctures. Mesoventrite punctate, without median ridge, fused with metaventral process. Mesanepisternum pubescent, rather finely punctate. Mesepimeron punctate, about four times as long as wide and about three times as long as interval to coxa. Median part of metaventrite flattened, fairly coarsely, irregularly and densely punctate. Lateral area of metaventrite with punctation similar to that on elytron; punctures well delimited, clearly smaller than puncture intervals, evanescent near metacoxal margin. Submesocoxal lines slightly convex, with marginal punctures smaller than punctures on lateral area of metaventrite and not extended laterally along margin of metaventrite. Submesocoxal areas about 0.02-0.03 mm long, about as fifth of shortest interval to metacoxae. Metanepisternum flat, fused with metaventrite, its margin indicated by outer puncture row of metaventrite. Tibiae straight. Abdomen not microsculptured. Ventrite I about as coarsely and densely punctate as lateral area of metaventrite, basal punctures not enlarged and not elongate, basal wrinkles or striae absent. Following ventrites finely punctate.

Male characters: Protarsomeres I to III slightly widened. Aedeagus ( Figs 4-6 ) 0.35-0.36 mm long, weakly sclerotized, symmetrical. Apical process abruptly narrowed near apex (lateral view), gradually narrowed in dorsal view. Parameres conspicuously sinuate, nearly evenly broad and bent dorsally in lateral view, hardly sinuate in dorsal view. Internal sac with complex sclerites as in Fig. 6 , with very short flagellar guide-sclerite, lacking membranous scale- or denticle-like structures.

Habitat: Secondary forests on limestone, litter from dead log and rotting leaves.

Distribution: Indonesia: Moluccas, Kai Besar Island.

Remarks: The species is also member of the B. lenta group, as shown by its aedeagal characters. It falls in the key to the Moluccan species ( Löbl, 2015a) to B. vicina Löbl, 2015 . It may be easily distinguished from the latter as from other congeners by the shape of the parameres and by the internal sac possessing a short flagellum and reduced flagellar-guide sclerite. The New Guinean B. praedicta Löbl, 2002 possesses parameres rather similar to those of B. incurva . It differs notably in external characters, in particular by the not fused metanepisterna and the very finely punctate metaventrite.

Figures

Figs 1-9. Baeocera humicola sp. nov. (1, 2) Aedeagus in dorsal and lateral views, scale bar = 0.1 mm. (3) Internal sac, scale bar = 0.05 mm. Figs 4-6. Baeocera incurva sp. nov. (4, 5) Aedeagus in dorsal and lateral views, scale bar = 0.1 mm. (6) Internal sac, scale bar = 0.05 mm. Figs 7-9. Baeocera notata sp. nov. (7) Aedeagus in dorsal view, scale bar = 0.1 mm. (8) Paramere in ventral view, scale = 0.05 mm. (9) Internal sac, scale = 0.05 mm.