Amphichroum nepalicum ( Coiffait, 1982 ) Shavrin, 2021

Shavrin, Alexey V., 2021, New species and records of the genus Amphichroum Kraatz, 1857 from the Himalayan Region and Tibet (Coleoptera: Staphylinidae: Omaliinae: Anthophagini), Zootaxa 5082 (1), pp. 1-14 : 9-10

Amphichroum nepalicum ( Coiffait, 1982) comb. nov.

( Figs. 5 , 17 , 21–22 )

Arpedium nepalicum Coiffait, 1982: 145

Type material examined: Holotype of Arpedium nepalicum Coiffait, 1982 , ♀: ‘Dzunda Khola-Tal | b. Talphi 3000- 3500 m’ <printed>, ‘Gebiet von Jumla | Westnepal, lg.H.Franz’ <printed>, ‘TYPE’ <red, printed>, ‘ Arpedium | nepalicum | H. COIFFAIT det.19[printed]79’ <handwritten>, ‘ Amphichroum [handwritten] | sp. [handwritten] | det. M. K. Thayer 198 9[handwritten]’ <printed>, ‘ Amphichroum | nepalicum Coiffait, 1982 | Shavrin A.V. det. 2015’ <printed> ( NHMW).

Additional material studied: 4 ♂♂, 5 ♀♀: ‘ NEPAL, W-Manaslu Himal Ngali Khola-Gebiet unterh Bhara Pokh. Lekh. 2200mNN N 28°22’34’’ E 84°29’52’’ 15./ 16.V.2005, leg. O. Jäger’ (2 ♂♂, 3 ♀♀: SNSD; 2 ♂♂, 2 ♀♀: cSh) ; 2 ♂♂, 2 ♀♀: ‘W Nepal, NW Pokhara, Modi Khola , 1600-2000 m. Landrung – Gandrung. 8.V.1984. C. Holzschuh leg.’ (1 ♂, 2 ♀♀: cZan; 1 ♂: cSh) ; 12 ♂♂, 10 ♀♀: ‘ NEPAL Manaslu Mts. 28°22’N 84°29’E E slope of N gali Khola Vall. 2000-2300 m. leg. Schmidt 15. V. 2005 ’ (3 ♂♂, 2 ♀♀: cSh; 9 ♂♂, 8 ♀♀: NME) ; 5 ♀♀: ‘ Nepal Manaslu Mts. | E-slope, E Gupchi | 2500-2700 m | Danda , 22.V.2006 | leg. J. Schmidt’ (2 ♀♀: cSh; 3 ♀♀: NME) ; 1 ♀: ‘ NEPAL, Prov. Mechi | 27°28’22’’N, 087°54’39’’E | Omje Khola bis | Yamphudin; 17.IV.2003 | 1700-2550 m NN | leg.: J. Weipert’ (cSh) .

Redescription. Measurements (n=30): HL: 0.29–0.41; HW: 0.48–0.61; AL (averaged): 1.28; OL: 0.15–0.17; PL: 0.54–0.66; PW: 0.73–0.91; ESL: 0.88–1.08; EW: 0.96–1.29; AW: 0.88–1.36;MTbL (averaged): 0.58; MTrL (averaged): 0.42 (MTrL 1–4: 0.20; MTrL 5: 0.22); AedL: 0.61–0.74; TL: 2.50 (holotype)–3.85.

Habitus as in Fig. 5 . Head and disc of pronotum yellow-brown; antennomeres 4–11 and abdomen reddishbrown; mouthparts, antennomeres 1–3, lateral portions of pronotum, elytra, legs and sometimes paratergites yellow. Head with dense transverse microsculpture, sparser and finer in middle portion; pronotum with very fine and sometimes indistinct transverse microreticulation, usually without meshes in middle and/or mediobasal third. Head with moderately fine, irregular punctation, denser in middle portion; punctation of pronotum about as that in middle portion of head, but slightly larger and deeper, sparser in middle and mediobasal portion; punctation of elytra larger and deeeper than that on pronotum, finer in parascutellar portion and along suture; punctation of abdomen invisible or very fine and sparse. Forebody with dense and short pubescence.

Head 1.4–1.6 times as broad as long, with deep and long anteocellar foveae, almost reaching level of anterior margins of eyes. Distance between ocelli about one and a half times distance between ocellus and posterior margin of eyes. Antennomere 3 slightly narrower than 2, 4 distinctly shorter and broader than 3, 5–6 slightly broader than 4, 7–10 slightly broader than 6.

Pronotum 1.3 times as broad as long, 1.4–1.5 times as broad as head, evenly narrowed both anteriad and posteriad.

Elytra 1.6 times as long as pronotum.

Male. Apical margin of abdominal tergite VIII and sternite VIII rounded. Aedeagus ( Figs. 21 ) with wide basal bulb of median lobe, narrowed toward middle; median lobe from preapical portion sharply narrowed toward subacute apex; parameres narrow, widened apically, significantly exceeding apex of median lobe, with two pairs of short apical and preapical setae; internal sac very long, with lateral fields of small and oval sclerites in middle and apical portions. Lateral aspect of aedeagus as in Fig. 22 .

Female. Apical margins of abdominal tergite VIII and sternite VIII rounded.

Comparative notes. Based on the coloration, length and general proportions of the body and aedeagus, A. nepalicum is similar to A. monticola and A. pindarense . From A. monticola it differs by the sparser punctation of the pronotum. From both species it can be distinguished by the details of the structure of the internal sac.

Distribution. Amphichroum nepalicum is known from several localities in Nepal ( Fig. 17 ).

Bionomics. Specimens were collected at elevations from 1600 to 3500 m a.s.l.

Remarks. Arpedium nepalicum was originally described based on a male from “ Népal (occidental), Dzunda, Khola Tal, près Talphi…”. I studied the holotype from NHMW, and based on the external morphology it is clearly belongs to the genus Amphichroum (see morphological features of the genus in Newton et al. 2020, Shavrin & Smetana (2018)). Thus, a new combination is proposed here.

Figures

FIGURES 1–7. Habitus of Amphichroum (males): 1—A. ahrensi (paratype), 2—A. altivagans (holotype), 3—A. anthobioides (lectotype), 4—A. monticola (holotype), 5—A. nepalicum (Nepal, Manaslu Himal), 6—A. pindarense (syntype), 7—A. telnovi (paratype). Scale bars: 1.0 mm.

FIGURES 15–17. Distribution of Amphichroum species in the Himalayan Region and Tibet: 15—A. ahrensi (circle), A. altivagans (triangle), A. anthobioides (squares), 16—A. monticola (circles), A. pindarense (triangles), A. telnovi (diamond), 17—A. nepalicum.

FIGURES 18–24. Aedeagus of Amphichroum monticola (18, 20: Nepal, Deorali, 19: Nepal, Khola Valley), A. nepalicum (21–22: Nepal, Manaslu Himal) and A. pindarense (23–24: Tibet, Rongshar Valley): 18, 21, 23—parameral view, 19—apical portion of aedeagus, parameral view, 20, 22, 24—lateral view. Scale bars: 0.1 mm.