Lomechusa parva Chen & Zhou

Chen, Yong-Jie & Zhou, Hong-Zhang, 2007, Taxonomy of the myrmecophilous genus Lomechusa (Coleoptera: Staphylinidae: Aleocharinae: Lomechusini) from China, Zootaxa 1606, pp. 29-39 : 32-33

Lomechusa parva Chen & Zhou , n. sp.

( Fig. 1 )

Type material. Holotype: CHINA: Tibet: male, Linzhi, ant nest, 18.VIII.2005, Jie Wu leg. Paratypes: 2 males, same data as holotype.

Description. Body length: 4.05–4.14 mm (from apex of head to apex of abdomen).

Measurements. HL: 0.69–0.72 mm; HW: 0.69 mm; PL: 0.84 mm; PW: 1.23–1.26 mm; EL: 1.05 mm; EW: 1.53 mm.

Body yellowish brown, head (only the basal part) and tergites II–VI black, pronotum and abdomen glossy, elytra dull.

Head with dorsal surface sparsely covered with golden soft hairs, directed anteriad, dorsally near eyes with four long hairs arranged in longitudinal row; large and shallow depression between eyes with short erect hairs and one tubercle. Eyes semitransparent, devoid of setae between facets, distinctly protruded laterally, eye diameter as long as temple length observed from above. Temples straight and convergent posteriad.

Antennae ( Fig. 1 g) long, almost reaching apex of elytra when deflected backward; each antennomere with fine soft hairs. Antennomere 1 twice as long as wide and twice as long as antennomere 2, 3 1.2 times as long as 2, antennomeres 4–10 nearly moniliform, somewhat elongate, last antennomere 0.34 mm long, slightly thinner than 8–10, distinctly shorter than 8–10 combined. Antennomere length ratios (from 1 to 11) are 0.9:0.45:0.55:0.55:0.6:0.65:0.65:0.65:0.6:0.6:1.15.

Pronotum ( Fig. 1 f) transverse, 1.46 times as broad as long. Dorsal surface with microsculpture and a few soft hairs. Disk slightly convex and glossy, with shallow medial groove. Lateral depressions almost absent. Anterior margin slightly emarginate, slightly wider than head, 0.86 as wide as posterior margin, narrow elevated strip along anterior margin present, punctures along anterior margin absent. Lateral margin straight. Hypomeron wide. Shallow medial fovea near posterior margin present. Posterior angles short and obtuse.

Elytra measured along suture 1.26 times as long as pronotum, dorsally weakly convex, with dense short pubescence directed posteriad. Lateral margins subparellell-sided, maximum width at apical 1/4, postero-lateral projection well defined.

Abdominal tergites with basal margin convex; tergites II–V with trichomes at lateral sides of each segment (reduced on tergite V); tergite III–V with fine golden hairs (sparser on IV and V) directed posteriad, tergites VI and VII smooth. Abdominal paratergites III and IV devoid of black setae. Chaetotaxy of tergites III–V: 11–12, 8–9, 4–5. Male tergite VIII as in Fig. 1 a, sternite VIII as in Fig. 1 b, tergites IX–X as in Fig. 1 d.

Aedeagus as in Figs. 1 c, e.

Remarks. The pronotal lateral depressions of the new species are not obvious and the disk of pronotum is sparsely covered with soft hairs, which distinguish the new species from all other congeners.

Host ant. All three specimens of L. parva were found under a big stone in the nest of Formica sinensis Wheeler, 1913 .

Distribution. China (Tibet)

Etymology. The species epithet is derived from the Latin word " parvus " (very fine, small).

Figures

FIGURE 1. Details of Lomechusa parva. a— tergite VIII; b— sternite VIII; c— medial lobe of aedeagus in lateral view; d— tergites IX – X; e— medial lobe of aedeagus in dorsal view; f— pronotum (microsculpture omitted); g— antennae (soft hairs omitted). Scale: a – d, 0.2 mm; e, 0.125 mm; f, g, 0.5 mm.