Amphichroum subaequale Shavrin & Smetana, 2018

Shavrin, Alexey V. & Smetana, Aleš, 2018, New species of the genus Amphichroum Kraatz, 1857 (Coleoptera: Staphylinidae: Omaliinae: Anthophagini) from China, Zootaxa 4508 (3), pp. 377-402 : 395-398

publication ID	https://doi.org/ 10.11646/zootaxa.4508.3.3
publication LSID	lsid:zoobank.org:pub:E53B4C53-554A-4913-8E3B-CE1C530DF004
DOI	https://doi.org/10.5281/zenodo.5963002
persistent identifier	https://treatment.plazi.org/id/DA218790-FFAF-2E32-248F-FC077A8BFD39
treatment provided by	Plazi
scientific name	Amphichroum subaequale Shavrin & Smetana
status	sp. nov.

Treatment

Amphichroum subaequale Shavrin & Smetana View in CoL , sp.n.

( Figs. 32 View FIGURES 32–34 , 35–36 View FIGURES 35–38 , 41 View FIGURE 41 )

Paratypes: 14 ♂♂ [two specimens were dissected], 6 ♀♀: same data as the holotype (2 ♂♂, 2 ♀♀: CS; 12 ♂♂, 4 ♀♀: NSMT) ; 1 ♂: ‘ CHINA: Shaanxi, Qing | Ling Shan, Hou Zen Zi | vill. To Taibai Shan’ <rectangular label, printed>, ‘alpine meadows | Z. Jindra, O. Šafránek | and M. Trýzna’ <rectangular label, printed> ( NSMT) ; 1 ♂: ‘ CHINA — Shaanxi prov. | Qing Ling Shan mts. | track Hou Zen Zi vill. | to Taibai Shan , 3500m, | 2–4 July 1998 ’ <rectangular label, printed>, ‘alpine meadows | Zd. Jindra, O. Šafránek | et M. Trýzna lgt.’<rectangular label, printed> ( NSMT) . All paratypes with red rectangular label ‘ PARATYPE | Amphichroum | subaequale sp.n. | Shavrin A. & Smetana A. des. 2018’.

Description. Measurements (n=25): HW: 0.62–0.72; HL: 0.35–0.39; AL(holotype): 1.40; OL: 0.17–0.20; PL: 0.57–0.69; PW: 0.90–1.12; ESL: 1.12–1.36; EW: 1.13–1.41; AW: 1.09–1.45; MTbL(holotype): 0.75; MTrL(holotype): 0.60 (MTrL 1–4: 0.35; MTrL 5: 0.25); AedL: 0.75–0.76; TL: 2.90–4.00 (holotype: 3.25).

Forebody yellow-brown, sometimes with darker posterior portion of head and neck; abdomen brown, with reddish-brown paratergites; antennomeres 4–11 and apical segment of maxillary palp brown; mouthparts, antennomeres 1–3 and legs yellow. Body, and particularly abdomen shiny. Head with small punctures on posterior portion of infraorbital ridges and sometimes between ocelli; pronotum with very sparse and small punctation, distinctly coarser and larger on lateral portions; punctation of elytra dense, deep and moderately large, denser and coarser on basal portion.

Head moderately transverse, 1.7–1.8 times as wide as long. Ocelli large, distance between ocelli about one and half times as long as distance between ocellus and posterior margin of eye. Apical segment of maxillary palp about 1.5 times as long as preceding segment, acutely narrowing from middle toward sharp apex.Antenna moderately long, reaching first third of length of elytra when reclined; length × width of antennomeres (holotype): 1: 0.15 × 0.05; 2: 0.12 × 0.04; 3: 0.15 × 0.04; 4: 0.10 × 0.05; 5: 0.11 × 0.06; 6–10: 0.12 × 0.06; 11: 0.17 × 0.07.

Pronotum very convex,1.2–1.6 times as wide as long, 1.4–1.5 times as wide as head, widest about middle, evenly narrowed both anteriad and posteriad, or slightly more narrowed posteriad; lateral portions widely flattened and slightly explanate.

Elytra slightly wider than long, slightly or distinctly widened apicad, reaching apical margin of abdominal tergite IV or basal part of tergite V, slightly less than twice as long as pronotum, with widely rounded or straight apical margins.

Metatibia 1.2 times as long as metatarsus.

Abdomen slightly narrower or wider than elytra, with very wide tomentose spots in middle of tergite IV.

Male ( Fig. 32 View FIGURES 32–34 ). Pronotum wide and convex. Protarsomeres 1–4 wide.Medial margin of apical part of protibia with two parallel rows of five slightly elongate peg setae; mesotibia slightly curved mediad, with dense row of sixteen to twenty short and wide thorns on medial margin, becoming slightly longer closer to apex; lateral margin of meso- and metatibia without or with several long strong thorns. Apical margin of abdominal tergite VIII slightly emargninated. Apical margin of abdominal sternite VIII straight or rounded. Aedeagus ( Fig. 35 View FIGURES 35–38 ) narrow, median lobe gradually narrowed apicad into a narrow elongate apical portion with narrowly arcuate apex; parameres narrow, exceeding apex of median lobe, with two pairs of apical and preapical short setae; internal sac long, with elongated rows of thorns in apical half and wide field of large thorns in basal portion. Aedeagus laterally as in Fig. 36 View FIGURES 35–38 .

Female. Pronotum narrow, less convex. Protarsomeres 1–4 moderately narrow. Pro- and mesotibiae without modifications. Abdominal tergite VIII and sternite VIII with rounded apical margin.

Comparative notes. Based on the wide body, coloration, proportions of pronotum and elytra, A. subaequale sp.n. is similar to A. miaoershanum , from which it differs by the wider parameres significantly exceeding median lobe of aedeagus. By the coloration of the body and general shape of the aedeagus, the new species is also similar to A. squamosum sp.n. and A. subelongatum sp.n. From A. squamosum sp.n. it differs by the absence of longitudinal impression on the pronotum, by the less curved metotibia in males, narrower median lobe and apex of the aedeagus. From A. subelongatum sp.n. it differs by the presence of well visible punctation on the head and distinctly narrower apical portion of median lobe and narrower parameres. From all above species it differs by the details of the internal sac.

Distribution. The new species is known from Qing Ling Shan range in Shaanxi, China ( Fig. 41 View FIGURE 41 ).

Bionomics. Specimens were collected at elevation 3500 m a.s.l. Collecting data are unknown.

Etymology. The specific epithet is a Latin adjective subaequalis, - e (almost identical). It alludes to the similar shape of the aedeagus of A. squamosum sp.n.