Anthobium crenulatum Shavrin & Smetana, 2019

Shavrin, Alexey V. & Smetana, Aleš, 2019, A revision of Eastern Palaearctic Anthobium Leach, 1819 (Coleoptera: Staphylinidae: Omaliinae: Anthophagini). III. Consanguineum, crassum and reflexum groups, and an additional species of the fusculum group, Zootaxa 4688 (4), pp. 451-482 : 463-465

Anthobium crenulatum Shavrin & Smetana , sp.n.

( Figs. 57 , 62–64 , 67 )

Type material examined: Holotype ♂ [dissected]: ‘ CHINA: Yunnan [ CH 07-02A], | Dali Bai Auton. Pref., Diacang Shan W | Dali , 25°41’20’’N, 100°06’12’’E | 3160 m, small creek valley, litter and | debris sifted, 28.V.2007, M. Schülke’ <rectangular label, printed >, ‘ HOLOTYPE | Anthobium | crenulatum sp.n. | Shavrin A.V. & Smetana A. 2018’ <red rectangular label, printed> ( CSC) .

Description. Measurements of the holotype: HW: 0.77; HL: 0.45; AL: 1.49; OL: 0.18; PL: 0.57; PW: 1.27; ESL: 1.52; EW: 1.55; AW: 1.50; MTbL: 0.80; MTrL: 0.35 (MTrL 1–4: 0.20; MTrL 5: 0.15); AedL: 0.72; TL: 3.40.

Body and antennomeres 6–11 reddish-brown, with mouthparts, antennomeres 1–5, lateral portions of pronotum, legs and apical tergites of abdomen yellow-brown. Head with irregular fine punctation, denser between grooves and infraorbital ridges, with narrow transverse impunctated portion in middle; neck with fine irregular punctures; pronotum with very dense punctation, markedly larger and deeper than that on head, with merging punctures on medioapical third, slightly sparser on lateral portions, with wide impunctated area after the middle of disc; punctation of elytra as that on pronotum, but slightly larger, somewhat finer on parascutellar portion, each elytron forming six very vague and tangled longitudinal rows of punctures. Habitus as in Fig. 57 .

Middle portion of head and infraorbital ridges slightly elevated, with indistinct semicircular impression between eyes at posterior third, with indistinct short grooves in front of ocelli, reaching posterior margin of eye; surface between punctures in middle transversely and in infraorbital ridges irregularly, diagonally elevated; postocular ridge smooth; anterior portion between antennal insertion and anterior margin of eye with distinct, wide semicircular notch. Ocelli situated at level slightly behind of postocular ridges; distance between ocelli about as distance between ocellus and posterior margin of eye. Length × width of antennomeres: 1: 0.21 × 0.07; 2: 0.12 × 0.06; 3: 0.13 × 0.07; 4: 0.12 × 0.07; 5–8: 0.13 × 0.07; 9: 0.12 × 0.07; 10: 0.11 × 0.07; 11: 0.16 × 0.07.

Pronotum distinctly more than twice as wide as long, 1.6 times as wide as head, widest in middle; lateral margins with four distinct, irregular projections similar to that in A. crassum sp.n.; middle portion with indistinct longitudinal and mediobasal portion with deep semicircular impressions; lateral portions wide and markedly explanate.

Elytra subparallel-sided, long, longer than combined wide, reaching basal margin of abdominal tergite V; surface of each elytron with diagonal distinct elevations between punctures on parascutellar portion and with indistinct longitudinal impression on mediobasal third along suture.

Male. Apical margins of abdominal tergite VIII and sternite VIII slightly emarginated. Aedeagus ( Fig. 62 ) with wide median lobe, gradually narrowed toward truncated apex; pararameres short, widened apically, with two small apical and preapical setae; internal sac very long, narrow in apical and markedly wide in basal portion. Aedeagus laterally as in Fig. 63 .

Female unknown.

Comparative notes. Based on the coloration, punctation, shape of the pronotum and general structure of the aedeagus, A. crenulatum sp.n. is similar to A. crassum sp.n., from which it can be distinguished by larger body, shorter elytra, and details of the external and internal characters of the aedeagus.

Distribution. The species is known only from the type locality in Diacang Shan range in Yunnan, China ( Fig. 64 ).

Bionomics. The holotype was collected at elevation 3160 m a.s.l. by sifting of litter and debris along a small creek ( CH 07-02A: Fig. 67 ).

Etymology. The specific epithet is the Latin adjective crenulatus,- a. -um (crenulate). It refers to the markedly crenulate lateral margins of the pronotum of the species.

Figures

FIGURE 64. Distribution of Anthobium crassum (black circles), A. crenulatum (black square), A. explanatum (black rhomb), and A. farkaci (black triangle) in the south-western China.

FIGURES 56–59. Habitus of species of Anthobium crassum-group: 56—A. crassum (holotype), 57—A. crenulatum (holotype), 58—A. explanatum (holotype), 59—A. farkaci (holotype). Scale bar: 1.0 mm.

FIGURES 60–63. Aedeagus of Anthobium crassum (60–61: paratype) and A. crenulatum (62–63: holotype): 60, 62—parameral view, 61, 63—lateral view. Scale bar: 0.1 mm.

FIGURES 65–68. Type locality of Anthobium crassum (65–66), A. crenulatum (67) and A. gaoligongshanense (68) in Yunnan, China (photograph: M. Schülke).