Amaurodera atra, Assing, 2019

Assing, Volker, 2019, On the Lomechusini fauna of the Palaearctic and Oriental regions. XXVI. New species, a new synonymy, and additional records (Coleoptera: Staphylinidae: Aleocharinae), Beiträge Zur Entomologie = Contributions to Entomology 69 (1), pp. 33-70 : 55-56

Amaurodera atra spec. nov.

urn:lsid:zoobank.org:act:7D5CCE81-D9AF-4599-B7C0-AA4D6D0AD8C2

(Figs 29–30, 124–128)

Type material: Holotype: “ PHILIPPINES – Mindanao , Mt. Hamiguitan Wildlife Sanctuary, Banakon creek, 6.74°N, 126.15°E, 400 m, wet litter & debris sifted, 22–24.III.2018, leg. Shavrin / Holotypus Amaurodera atra sp. n., det. V. Assing 2018” (cAss). Paratypes: 1, 4: same data as holotype (cAss); 4, 2: “ PHILIPPINES: Mindanao , Sitio Bitaugan, Kawa-kawa River, 300 m, 6°46'31"N, 126°08'41"E, stream bank, wet litter, debris, dead wood, 24–26.III.2018, leg. Shavrin ” (cAss) .

Etymology: The specific epithet (Latin, adjective) alludes to the uniformly black coloration of the body, a character distinguishing this species from the congeners previously recorded from the Philippines.

Description: Body length 3.9–4.9 mm; length of forebody 2.0– 2.4 mm. Habitus as in Fig. 29. Other measurements: head width: 0.8 mm; length of pronotum: 0.75–0.85 mm; width of pronotum: 0.55–0.60 mm; elytral width: 0.75– 0.85 mm. Coloration: whole body black, except for the yellowish-brown abdominal segments IX–X and the posterior margin of segment VIII; legs distinctly bicoloured with the profemora and most of the meso- and metafemora blackish and with the tibiae, tarsi, and the bases of the meso- and metafemora yellowish; antennae blackish-brown to blackish with the basal two antennomeres usually somewhat paler brown and with the apical 3–5 antennomeres dark-yellow; maxillary palpi darkbrown with the apical palpomere pale-yellowish.

Head (Fig. 30) weakly transverse; dorsal surface with or without shallow isodiametric microsculpture; punctation very fine and rather sparse. Eyes distinctly convex, approximately as long as distance from posterior margin of eye to posterior constriction. Antenna 2.0– 2.1 mm long; antennomere IV approximately twice as long as broad; antennomeres V–X gradually decreasing in length and decreasingly oblong, X weakly oblong.

Pronotum (Fig. 30) approximately 1.25 times as long as broad and as broad as head, without sexual dimorphism; dorsal surface opaque due to very dense microgranules; midline with narrow sulcus reaching neither anterior nor posterior margins; antero-laterally with sparse short setae on either side.

Elytra (Fig. 30) approximately 0.6 times as long as pronotum; punctation fine and rather dense; interstices without microreticulation, except near anterior margins. Hind wings present. Metatarsomere I shorter than the combined length of II–IV.

Abdomen narrower than elytra; tergites III–V with rather shallow anterior impressions; punctation fine and sparse; tergites V–VII with very shallow transverse microsculpture, tergites III–IV with more distinct transverse or oblique microsculpture, tergite VIII with pronounced microsculpture composed of short transverse meshes; posterior margin of tergite VII with palisade fringe; posterior margin of tergite VIII crenulate.

: posterior margin of sternite VIII strongly convex; median lobe of aedeagus 0.53–0.58 mm long and shaped as in Figs 124–125.

: posterior margin of sternite VIII broadly convex; spermatheca (Figs 126–128) with distinctly dilated proximal and distal portions and with slender median portion.

Comparative notes: Two species of Amaurodera were previously known from the Philippines, A. philippina CAMERON, 1941 (primary sexual characters unknown) from Siargao Island and A. orousseti PACE, 1990 from Luzon ( ASSING 2016b). The new species is distinguished from them as follows:

from A. philippina by larger body size ( A. philippina : body length 3.2 mm) and by the coloration ( A. philippina : pronotum brown; elytra brownish-yellow; abdomen with segments III–V reddish and segments VIII and the posterior margin of VII yellow; antennae and legs reddish-yellow);

from A. orousseti by larger body size ( A. orousseti : body length 4.0 mm), the coloration ( A. orousseti : body brownish-red with brown pronotum; legs yellowish-red with the femora and the protibiae brown; antennae darkred with antennomeres I–II and XI reddish), by the shape of the aedeagus ( A. orousseti : ventral process apically more acute in ventral view), and by the shape of the spermatheca ( A. orousseti : proximal and distal portions less strongly dilated; median portion less slender; distal cuticular invagination acute). For illustrations of the primary sexual characters of A. orousseti see PACE (1990).

Amaurodera atra differs from the widespread and variable A. kraepelini FAUVEL, 1905 by the primary sexual characters, particularly the shape of the spermatheca ( A. kraepelini : distal portion weakly dilated; proximal portion more strongly dilated).

Distribution and natural history: The type specimens were collected in two geographically close localities in the southeast of Mindanao, Philippines, by sifting wet litter and debris near running water at altitudes of 300 and 400 m.