Amaurodera longisetosa, Assing, 2017

Assing, Volker, 2017, On the Lomechusini fauna of the East Palaearctic and Oriental regions, with a focus on the genera Orphnebius and Amaurodera (Coleoptera: Staphylinidae: Aleocharinae), Beiträge Zur Entomologie = Contributions to Entomology 67 (1), pp. 63-106 : 96-97

Amaurodera longisetosa spec. nov.

urn:lsid:zoobank.org:act:887533D9-985B-41FE-B3C8-F1FF8938DC8B

Figs 14 , 55–56 , 160–163 )

Type material: Holotype ♂: “ SABAH: Crocker Ra., 1350 m, km 60 Kota Kinabalu–Tambunan , 17.V.1987 Burckhardt - Löbl / Holotypus ♂ Amaurodera longisetosa sp. n., det. V. Assing 2016” ( MHNG). Paratypes: 8 exs.: “ SABAH: Crocker Ra., 1270 m, km 60 rte Kota Kinabalu–Tambunan , 17.V.87, Burckhardt - Löbl ” ( MHNG, cAss); 1 ♀: “ SABAH: Poring Hot Springs , 550–600 m, 9.V.1987, Burckhardt - Löbl ” ( MHNG); 1 ♀: “ SABAH Danum Valley, B.R.L., f.i.t. 14–16.II.2007, G. de Rougemont ” (cRou) .

Etymology: The specific epithet (adjective) alludes to the long setae on the pronotum.

Description: Body length 4.4–5.5 mm; length of forebody 2.2–2.6 mm. Other measurements: head width: 0.60–0.78 mm; length of pronotum: 0.78–0.98 mm; width of pronotum: 0.58–0.71 mm; elytral length at suture: 0.48–0.58 mm; elytral width: 0.88–1.05 mm. Coloration ( Figs 14 , 55 ): head dark–brown to blackish; pronotum dark–brown to blackish-brown; elytra dark reddish to reddish-brown with the postero-lateral portions extensively darker; abdomen blackish-brown with the anterior segments usually slightly – or partly – paler; legs palebrown, usually with the profemora and the apical halves of the meso- and metafemora, sometimes also the basal portions of the meso- and metatibiae, somewhat darker; antennae dark-brown to blackish-brown with the apical antennomeres more or less extensively yellow to darkyellow; maxillary palpi brown to dark-brown with the terminal palpomere yellowish.

Head ( Fig. 55 ) posteriorly nearly truncate and of very variable shape (see measurements), in larger specimens relatively larger and more transverse than in smaller specimens; postero-lateral outline between eyes and posterior constriction more or less strongly convex in dorsal view; median dorsal portion not impressed; punctation moderately sparse and fine; interstices with or without extremely shallow traces of microreticulation visible only at high magnification (100 x). Eyes moderately large and convex, 0.5–0.7 times as long as distance from posterior margin of eye to posterior constriction (relative size dependent on relative head size, smaller in large-headed than in smallheaded specimens). Antenna ( Fig. 14 ) long and slender, 2.3–2.7 mm long; antennomere IX approximately twice as long as broad and antennomere X approximately 1.5 times as long as broad.

Pronotum ( Fig. 56 ) moderately slender, approximately 1.36 times as long as broad, without sexual dimorphism; dorsal surface with very dense microgranules and opaque; midline with narrow median sulcus reaching neither anterior nor posterior margins; lateral portions with 4–6 long, stout, and erect black setae on either side; anterolateral portions additionally with some short setae.

Elytra ( Fig. 55 ) approximately 0.6 times as long as pronotum; punctation extremely fine (barely noticeable even at high magnification) and moderately dense; microreticulation absent. Hind wings fully developed. Legs including tarsi long and slender; metatarsomere I shorter than the combined length of II and III.

Abdomen narrower than elytra; tergites III–V with moderately deep anterior impressions; tergites III–VII with sparse punctures on disc (especially laterally) and at posterior margin; tergal surfaces with nearly obsolete microreticulation visible only at high magnification (100 x); posterior margin of tergite VII with palisade fringe; posterior margin of tergite VIII weakly convex and serrate.

♂: median lobe of aedeagus ( Figs 160–162 ) approximately 0.6 mm long; ventral process of distinctive shape, basally broad, lateral margins angled in ventral view.

♀: spermatheca shaped as in Fig. 163 .

Intraspecific variation: Body size, head shape, and relative head size are remarkably variable. Moreover, the spermatheca of the female from Poring Hot Springs differs by shorter length (0.30 mm) and the shape of the distal portion. However, since no additional differences were observed, this is attributed to intra- rather than interspecific variation.

Comparative notes: Amaurodera longisetosa is characterized particularly by the variability of the size and shape of the posteriorly truncate head, the chaetotaxy of the pronotum, and the primary sexual characters. Using the key to the Amaurodera species of Borneo in PACE (2008a), it would key out at couplet 4, together with A. similis CAMERON, 1928 ( Sarawak) , from which it additionally differs by larger body size and darker coloration. Regarding the presence of long setae in the antero-lateral portions of the pronotum and the long proximal portion of the spermathecal capsule, A. longisetosa is similar to A. amabilis , from which it is distinguished by much longer and broader elytra, a posteriorly nearly truncate head, slightly larger and more bulging eyes, and a darker abdomen.

Distribution and natural history: The type specimens were collected in four close localities in Sabah at altitudes of 550–1350 m, in one locality together with A. frondium . One paratype was collected on the wing.

Figures

Figs 1–30: Antenna (1–19), forebody (20, 23, 26), abdomen (21, 24, 27, 29), antero-lateral portion of abdomen in lateral-dorsal view (22, 25, 28), and abdominal segment VII (30) of Orphnebius triacuminatus (1, 20–22), O. gracilis (2, 23–25), O. protuberatus (3, 26–28), O. pertortus (4, 29–30), O. reticulipennis (5), Zyrastilbus almorensis (6), Pheidologitonetes bursata (7), Rabdotodrusilla vara (8), Amaurodera bicarinata (9), A. gilvicornis (10), A. latisulcata (11), A. brevipes (12), A. migritheca (13), A. longisetosa (14), A. calicitheca (15), Drusilla smetanai (16), D. nepalensis (17), D. lativentris (18), and Witteia tensa (19). Scale bars: 1–29: 1.0 mm; 30: 0.5 mm.

Figs 43–57: Amaurodera bicarinata (43–46), A. gilvicornis (47–48), A. latisulcata (49–50), A. brevipes (51), A. migritheca (52–54), A. longisetosa (55–56), and A. calicitheca (57): forebody (43, 47, 49, 51, 52, 55, 57); pronotum in dorsal view (44, 50, 53); pronotum in dorso-lateral view (45, 56); abdomen (46, 48, 54). Scale bars: 43, 46–49, 51–52, 54–55, 57: 1.0 mm; 44–45, 50, 53, 56: 0.5 mm.

Figs 150–172: Amaurodera frondium (150–151), A calicitheca (152–158), A. discoidea, paratype (159), A. longisetosa (160–163), A. bulbosa (paratypes of A. discoidea from Sabah) (164–165), Rabdotodrusilla vara (166–169), and Witteia tensa (170–172): median lobe of aedeagus in lateral and in ventral view (150–155, 160–162, 164–165, 168–169, 170–171); apical portion of median lobe in ventral view (156); spermatheca (157–159, 163, 172); male tergite VIII (166); male sternite VIII (167). Scale bars: 150–155, 157–165: 0.5 mm; 166–172: 0.2 mm; 156: 0.1 mm.