Lomechusoides drobovi Jászay, Hlaváč & Baňař, 2023

Jászay, Tomáš, Hlaváč, Peter & Baňař, Petr, 2023, A taxonomic revision of the myrmecophilous genus Lomechusoides Tottenham, 1939 (Coleoptera: Staphylinidae: Aleocharinae). Part II. The revision of the strumosus species group, Zootaxa 5343 (6), pp. 539-593 : 546-547

Lomechusoides drobovi Jászay, Hlaváč & Baňař sp. nov.

Figs 8–11

Etymology. The species is named after the Russian collector of the new species, V. N. Drobov.

Material studied. HOLOTYPE, ♀: RUSSIA: (h) Вилюйский окр. Rкут. обл. р. Чoна от устьЯ Окунайки до РоссурЯх, В. Н. Дробов 27.7.– 2.8.1914 г. [=Вилюйский округ Rкутской области река Чoна от устьЯ Окунайки до РоссурЯх, В. Н. Дробов 27.7.– 2.8.1914 года, =Vilyuyskiy okr. Yakut. obl. r. Chona ot ust´ya Okunayki do Rossuryakh , V. N. Drobov, 27.7.– 2.8.1914 g. = Vilyuyskiy region Yakutia, river Chona from Okunayka flow into Rossuryakh, V. N. Drobov 27.7.– 2.8.1914] / (h) Lomechusa inflata Zett. (p) Kirschenblatt det. / red label (p) HOLOTYPE ♀ Lomechusoides drobovi sp. nov., T. Jászay, P. Hlaváč & P. Baňař det., 2021 ( ZIN) .

Description. Body light reddish-brown ( Fig. 8 ) except anterior part of frontal median impression, clypeus, labrum, antennae, narrow posterior margin of pronotum, anterior margin of visible tergites II–VII and anterior margin of visible sternites V–VII brown.

Head trapezoidal, dull, slightly longer than wide, ratio HW/HL: 0.93, with deep, broad, round frontal median impression which is evenly microsculptured by fine, shallow punctures; disc of head dull, microsculptured and with very fine punctures; length of eyes 0.25x of length of head; eyes very slightly protuberant, temples behind eyes straight, convergent posteriad.

Antennae long, scape 1.53x as long as wide and 2.85x as long as pedicel, pedicel 0.87x, antennomere III: 1.25x, IV as long as wide, antennomeres V–VIII oval elongate, terminal antennomere slender and acute, 1.35x as long as scape, relative length of antennomeres from base to apex: 20: 7: 10: 10: 12: 13: 13: 13: 13: 13: 27.

Pronotum ( Fig. 9 ) trapezoidal and slightly asymmetric, ratio PW/PL: 1.70, with long concave anterior margin, anterior corners rounded, slightly obtuse, lateral sides in anterior first thirds shortly rounded, in posterior two thirds almost straight and divergent posteriad, posterior corners acute, bearing deep lateral microsculptured and sparcely punctate impressions, pronotal disc unevenly microsculptured, with sparse and uneven punctures, tubercles slightly visible, median line slightly defined; in lateral view, lateral margins thick, slightly narrowed anteriad, in posterior half equally thinned posteriad, lacking visible sharp edge; maximal pronotal width close before posterior corners, elytra in humeri slightly wider than late; pronotum with reduced number of macrosetae, anterior margin with two macrosetae, lateral margins of posterior corners with one macroseta.

Anterior and lateral margins of metaventral process ( Fig. 10 ) concave, with divergent lateral lines anteriad, anterior margin with transversal elevation, posterior part in median line with lentil-like impression, metaventral process microsculptured and punctate; metaventral disc in posterior part on sides with short longitudinal impressions, metaventrite microsculptured and sparsely punctate with short setae not reaching margin of adjacent puncture.

Elytra finely punctate, 1.06x as long as pronotum, ratio EW/EL: 1.74; anterior part with about three macrosetae, humeral part lacking macrosetae, distance between punctures on disc about two to two and a half times longer than diameter of puncture.

Abdomen with visible tergite II densely punctate and setaceous, visible tergites III–V with sparse puncturation and setation only on posterior margin, visible tergites VI–VII at posterior and lateral margins finely and sparsely punctate, posterior part lacking puncturation, visible tergites II–VII unevenly microsculptured.

Male unknown.

Spermatheca ( Fig. 11 ) with apical part 1.80x as long as basal part and 1.33x as wide as basal extended part, 3.15x as long as wide, apical part equaly wide, subparallel, apex rounded, linkage arm between apical and basal part visibly slender.

Measurements. (♀, Holotype): TL 4.65 mm; FB 2.45 mm; HL 0.75 mm; HW 0.70 mm; antennal length 2.35 mm; PL 0.90 mm; PW 1.45 mm; EL 0.95 mm; EW 1.65 mm; FTL 0.85 mm; MTL 1.05 mm; HTL 1.25 mm.

Differential diagnosis. L. drobovi is separated from the most similar L. chekanovskiyi by the shape of the pronotum, the presence of the impression on the metaventral process, and by the shape of the spermatheca. From L. poppiusi it differs by the darker colour of the head, and from L. inflatiformis and L. inflatus by the unicoloured pronotum.

Host ant. Unknown.

Distribution. Russia (Yakutia).

Figures

FIGURES 8–11. Lomechusoides drobovi sp. nov., female holotype. 8, dorsal habitus; 9, pronotum in dorsal view (L: 0.90 mm, W: 1.45 mm); 10, metaventral process; 11, spermatheca. Scale bar in mm.