Apatetica gibba, Assing, 2018

Assing, Volker, 2018, On some species of Apatetica WESTWOOD (Coleoptera: Staphylinidae: Apateticinae), Beiträge zur Entomologie = Contributions to Entomology 68 (2), pp. 347-359 : 356-358

Apatetica gibba spec. nov.

urn:lsid:zoobank.org:act:51D50FDD-A847-43CC-9760-A14D6BC90FE5

( Figs 34–38 )

Type material: Holotype ♂: “ CHINA: S-Gansu [ CH 12- 06] 2012, W-Qinling Shan, 47 km N Chengxian, 34°10'20"N, 105°42'10"E, 1830 m, creek valley with second. deciduous forest, litter sifted, 29.VII. Schülke / Holotypus ♂ Apatetica gibba sp. n. det. V. Assing 2018” ( MNB). Paratype ♀: “ CHINA [6] - S-Gansu, N Chengxian, W-Qinling Shan, 34°10'20"N, 105°42'10"E, 1830 m, 29.VII.2012, V. Assing” (cAss).

Etymology: The specific epithet (Latin, adjective: domed, convex) alludes to strongly convex pronotum (crosssection), one of the characters distinguishing this species from the similar A. laevicollis .

Description: Body length 6.6–6.8 mm; length of forebody 5.6–5.8 mm. Other measurements: headwidth 1.3–1.4 mm; length of antenna 2.7–2.9 mm; width of pronotum: 2.7–2.9 mm; length of pronotum 1.6 mm; length of elytra 2.6–2.8 mm; length of metatibia 1.5–1.6 mm. Habitus as in Fig. 34 . Coloration: body black with the lateral margins of the pronotum dark reddish-brown, the apices of the elytra brown, the posterior margins of the abdominal segmentsVI-VII dark-reddish, and tergite VIII reddish-yellow to reddishbrown; legs dark-brown to blackish with tarsomeres I–IV brown and tarsomeres V dark-yellow; antennae black with the basal three to five antennomeres reddish to dark reddish-brown.

Head ( Fig. 35 ) strongly transverse; frons and vertex with moderately fine and rather dense punctation and with

shallow microsculpture; median portion of vertex weakly elevated, nearly flat; near dorsal margin of eyes with very dense and somewhat coarser punctures and with distinct microsculpture. Antenna moderately long; antennomeres IV and Vapproximately twice as long as broad, VI nearly twice as long as broad, VII approximately 1.5 times as long as broad, VIII and IX weakly oblong, and Xapproximately as long as broad.

Pronotum ( Fig. 35 ) approximately 1.7–1.8 times as broad as long and approximately 2.1 times as broad as head, broadest near posterior angles; disc strongly convex in cross-section, near posterior angles flattened; posterior angles sharply marked and directed posteriad; lateral margins narrowly separated in anterior half; disc with regularly distributed dense and extremely fine punctation; interstices with very shallow, partially nearly obsolete microsculpture.

Elytra 1.63–1.75 times as long as pronotum; each elytron with eight fine and mostly impunctate striae (punctures may be weakly indicated in places, particularly in the posterior portion of the elytra); intervals flat, with scattered and extremely fine micropunctation visible only at high magnification, without microsculpture and glossy. Scutellum weakly transverse. Legs rather short and stout; protarsomeres I–IV weakly dilated, without sexual dimorphism.

Abdomen ( Fig. 36 ) with microsculpture composed of a mix of isodiametric and transverse meshes of variable length; punctation fine and rather sparse; tergite VIII sexually dimorphic.

♂: tergite VIII distinctly tapering posteriad, with the posterior margin strongly convex; aedeagus ( Figs 37–38 ) 1.7 mm long; ventral process acute apically in ventral view, not bent dorsad in lateral view; parameres flattened, apically acute and bent ventrad, extending slightly beyond apex of ventral process.

♀: tergite VIII more distinctly wedge-shaped than in male, with the apex narrowly truncate.

Comparative notes: Based on the similar external and male sexual characters, A. gibba is closely allied to A. laevicollis and A. glabra . It is distinguished from them as follows:

from A. laevicollis by a much more convex pronotum (cross-section), the coloration ( A. laevicollis : pronotum, elytra, antennae, and abdomen completely black), a head with distinct microsculpture and finer, more regularly distributed, and less dense punctation, a much more convex pronotum without macropunctation, with finer and denser micropunctation, and with microsculpture, elytra with mostly impunctate striae and with very scattered micropunctation, an abdomen with much finer and much sparser punctation, and by an apically less acute median lobe of the aedeagus;

from A. glabra by smaller body size, a less broad habitus, the presence of microsculpture on the head and the pronotum, the absence of distinct rugae near the dorsal margins of the eyes, much finer punctation of the pronotum, nearly impunctate striae of the elytra, and a distinctly smaller aedeagus with a less slender median lobe.

Distribution and natural history: The type locality is situated in the western portion of the Qinling Shan in South Gansu. The type specimens were sifted from moist litter in a dense secondary deciduous forest with rich undergrowth at an altitude of 1830 m.

Figures

Figs 34–43: Apatetica gibba (34–38) and A. curtipennis (39–43): habitus (34, 39); head and pronotum (35, 40); posterior portion of elytra and abdomen (36, 41); aedeagus in lateral and in ventral view (37–38, 42–43). Scale bars: 34, 39: 5.0 mm; 35–38, 40–43: 1.0 mm.