Baeocera obscura Löbl, 2021

Löbl, Ivan, Leschen, Richard A. B. & Warner, William B., 2021, Scaphisomatini of Arizona (Coleoptera, Staphylinidae, Scaphidiinae) collected by V-Flight Intercept Traps, Revue suisse de Zoologie 128 (1), pp. 173-185 : 177

Baeocera obscura Löbl , sp. nov.

Figs 6-8

Material examined:

Holotype: MHNG (# MHNG-ENTO-86102); male; USA: AZ: Cochise Co. Huachuca Mts. ; 0.8 rd. mi. SW Reef; 31.4238° - 110.2991°; Aug. 31 - Sept. 28, 2018; V-flight intercept trap; W.B. Warner.

Paratypes: WBWC, MHNG; 4 females, with the same data as the holotype. – MHNG; 1 female; with the same data but July 4-24.2019.

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

Diagnosis: The species is defined by the following characters in combination: body length about 1.0- 1.20 mm, body light brown, lateral margins of pronotum and elytra separately arcuate, elytron with basal stria broadly separated from lateral stria, lateral parts of metaventrite with hardly visible punctation, ventrite I without basal striae, aedeagus as Figs 6-8 , weakly sclerotized, symmetrical and narrow, parameres nearly throughout evenly narrow and weakly curved, internal sac lacking sclerites, with very thin, weakly sclerotized flagellum.

Description: Length 1.06-1.20 mm, width 0.73- 0.84 mm. Body light brown, pronotum and elytra sometimes somewhat lighter than venter of thorax and abdomen. Femora, tibiae and antennomeres I and II about as light as venter of thorax, tarsi and antennomeres III to XI lighter, yellowish. Antennomere II slightly longer than antennomere III. Length/ width ratios of antennomeres as: III 16/5: IV 16/5: V 23/5: VI 18/7: VII 24/11: VIII 23/10: IX 30/12: X 28/14: XI 28/15. Pronotum and elytra separately arcuate, both with punctation fine, hardly visible at 50 times magnification, pronotal microsculpture indistinct. Marginal carinae of pronotum not visible in dorsal view. Point of scutellum exposed. Elytron weakly narrowed apically, with lateral margin weakly rounded, adsutural area flat and broad, sutural stria impunctate, curved along base to form basal stria extended slightly outward basal half of elytral width and broadly separated from lateral stria, not approximate to basal margin; lateral stria appearing impunctate. Elytral disc with distinct punctulate microsculpture. Hypomeron impunctate. Mesepimeron about three times as long as wide and six times as long as distance to coxa. Median part of metaventrite flattened, with distinct U-shaped row of fine punctures. Remaining punctation on metaventrite hardly visible at 100 times magnification. Submesocoxal lines convex, with row of small, not elongate pits, not extended laterally. Submesocoxal areas 0.03 mm long, about as third to fourth of shortest distance to metacoxae. Exposed part of metanepisternum flat, 0.06 to 0.08 mm wide, with suture deep, impunctate, straight or somewhat curved. Protibiae and mesotibiae straight, metatibiae hardly curved. Abdominal punctation as fine as that on elytra, microsculpture punctulate, distinct. Ventrite I without basal striae, basal row of fine pits interrupted at middle. Aedeagus ( Figs 6-8 ) 0.29 mm long, weakly sclerotized.

Distribution: USA, Arizona.

Type locality: Arizona, Cochise Co. Huachuca Mts. , 0.8 rd. mi. SW Reef, 31.4238°N, 110.2991°W.

Remarks: The sole available male has the tip of the median lobe broken off and the basal bulb deformed, though the distinguishing characteristics are retained for naming this species. The shape of the median lobe and parameres of this species are similar with those in members of the B. picea group as defined by Löbl & Stephan (1993) while the presence of a flagellum and the internal sac lacking proximal sclerotized structures suggest relationship with members of the B. apicalis group. Notable is the very thin flagellum much narrower than that in its North American congeners. The new species falls in the key to the North American Baeocera under the couplet 12, to B. similaris Löbl & Stephan, 1993 . It differs drastically from B. similaris by the elytral and abdominal microsculpture, and by the ventrite I margined by round, not elongate, pits.

Figures

Figs 3-10. Aedeagi in Baeocera. (3 - 4) B. arizonensis Löbl, sp. nov., in dorsal and lateral views, scale = 0.1 mm. (5) Ditto, paramere in ventral view, scale = 0.1 mm. (6-7) B. obscura Löbl, sp. nov., in dorsal and lateral views, scale = 0.1 mm (basal bulb deformed, tip of apical process broken). (8.) Ditto, paramere in ventral view, scale = 0.05 mm. (9-10) B. vintercepta Löbl, sp. nov., in dorsal and lateral views, scale = 0.1 mm.