Anthobium flaveolum Shavrin & Smetana, 2018

Shavrin, Alexey V. & Smetana, Aleš, 2018, A revision of Eastern Palaearctic Anthobium Leach, 1819 (Coleoptera: Staphylinidae: Omaliinae: Anthophagini). II. fusculum group, and two additional species of the nigrum group, Zootaxa 4508 (4), pp. 451-506 : 498-500

Anthobium flaveolum Shavrin & Smetana , sp.n.

( Figs. 95 , 98–100 )

Type material examined: Holotype ♂ [specimen dissected]: ‘ NEPAL:nr. Sanghu [underlined by yellow] | Middle oak for. [handwritten] | 27°19[handwritten]'N,87°31[handwritten]' | 26.x. [handwritten]1961 [1-handwritten] | c. 9350 ft. [handwritten]’ <rectangular label, printed>, ‘ Funnel sample | no. 155[handwritten]’ <rectangular label, printed>, ‘BMNH Nepal [underlined by yellow] | Exp. 1961-1962 | B.M. 1975-287’ <rectangular label, printed >, ‘ HOLOTYPE | Anthobium | flaveolum sp.n. | Shavrin A. & Smetana A. 2018 ’ <red rectangular label, printed> ( BMNH) .

Paratype ♀: same data as the holotype , ‘ PARATYPE | Anthobium | flaveolum sp.n. | Shavrin A. & Smetana A. 2018 ’ <red rectangular label, printed> ( BMNH) .

Description. Measurements (n=2): HW: 0.67–0.71, HL: 0.40–0.44; AL(holotype): 1.09; OL: 0.17–0.19; PL: 0.50–0.54; PW: 1.07–1.15; ESL: 1.47–1.48; EW: 1.47–1.48; AW: 1.17–1.20; MTbL(holotype): 0.70, MTrL(holotype): 0.35 (MTrL 1–4: 0.25; MTrL 5: 0.10); AedL: 0.40; TL: 3.15(holotype)–3.64.

Body elongate, very convex. Head reddish brown; antennomeres 4–11, pronotum, elytra and abdomen yellowbrown; mouthparts, antennomeres 1–3, lateral portions of pronotum and elytra, and legs yellow. Body very shiny, without microsculpture except for anterior portion of head between antennal insertion, and anterior margin of eye and posterior portions of head behind eyes with traces of transverse fine microsculpture; abdomen with distinct isodiametric microsculpture. Head with irregular small punctation, with moderately wide impunctate areas in middle and on infraorbital ridges; middle part of neck with several small punctures; pronotum with irregular and sparse punctation, markedly deeper than that on head, denser on medioapical portions, with wide impunctate area between mediobasal impression; scutellum with several small punctures; punctation of elytra larger and deeper than that on pronotum, denser and smaller on parascutellar area and along suture, each elytron with indistinct six, vague and tangled longitudinal rows of punctures, with moderately wide impunctate longitudinal areas between rows 3 and 4; abdominal tergites without visible punctation. Habitus as in Fig. 95 .

Head 1.6 times as wide as long; middle portion of head somewhat flattened or very gently elevated, without or with (holotype) very indistinct transverse impression in middle; occipital furrow between ocelli wide and deep; grooves in front of ocelli narrow and deep, reaching posterior third of length of eye; postocular ridges smooth; anterior portion between antennal insertion and anterior margin of eye with wide semicircular notch. Ocelli large and convex, situated at level of posterior margins of eyes, distance between ocelli slightly longer than distance between ocellus and posterior margin of eye. Length × width of antennomeres (holotype): 1: 0.13 × 0.05; 2: 0.10 × 0.04; 3: 0.11 × 0.04; 4: 0.08 × 0.04; 5: 0.08 × 0.05; 6–8: 0.09 × 0.05; 9: 0.09 × 0.06; 10: 0.08 × 0.06; 11: 0.15 × 0.06.

Pronotum slightly more than twice as wide as long, 1.5–1.6 times as wide as head, widest in middle, slightly more narrowed posteriad than anteriad; anterior angles widely rounded, slightly protruded anteriad; posterior angles more or less rectangular; lateral edges of pronotum with very indistinct, irregular smooth crenulation; disc of pronotum with wide, convex middle elevation with distinct and wide, moderately deep semicircular impression on mediobasal third; lateral portions wide and distinctly explanate, each with very deep oval pit slightly in front of middle.

Elytra as wide as long, slightly widened to apical third and widely rounded apically, reaching basal margin of abdominal tergite V, slightly less than three times as long as pronotum; lateral portions narrow, slightly elevated; latero-apical margins with five relatively large, acute teeth of crenulation becoming flattened toward middle.

Abdomen very narrow, with indistinctly elevated paratergites, with a pair of small, rounded tomentose wingfolding spots near apical margin of tergite V.

Male. Apical margins of abdominal tergite VIII and sternite VIII slightly sinuate. Aedeagus ( Fig. 98 ) with median lobe wide basally, gradually narrowing toward rounded apex; parameres rather short, somewhat exceeding apex of median lobe, with two apical and preapical setae; internal sac simple, very narrow. Aedeagus laterally as in Fig. 99 .

Female. Apical margin of abdominal tergite VIII straight. Apical margin of abdominal sternite VIII rounded.

Comparative notes. Anthobium flaveolum Shavrin & Smetana , sp.n. may be distinguished from all remaining species of the nigrum group by the pale coloration of the body, the very indistinct lateral crenulation of the pronotum, the moderately large teeth on latero-apical margins of elytra, and by the shape and internal structure of the aedeagus.

Distribution. The species is known only from the type locality in eastern Nepal ( Fig. 100 ).

Bionomics. Specimens were collected at elevation about 2800 m a.s.l. The detailed ecological data are unknown.

Etymology. The specific epithet is the Latin adjective flaveolus, - a, - um (yellowish). It refers to the coloration of the body.

Figures

FIGURE 100. Distribution of Anthobium alticola (black circles) and A. flaveolum (black square) in the Himalayan Region.

FIGURES 94–95. Habitus of Anthobium nigrum group: 94—A. alticola (NEPAL: Annapurna Mts.) and 95—A. flaveolum (paratype). Scale bar: 1.0 mm.

FIGURES 96–99. Aedeagus of Anthobium alticola (96–97: NEPAL: Annapurna Mts.) and A. flaveolum (98–99: holotype): 96, 98—parameral view, 97, 99—lateral view. Scale bar: 0.1 mm.