Sarothrias sinicus Bi & Chen

Bi, Wen-Xuan, Chen, Chang-Chin & Lin, Mei-Ying, 2015, First record of Jacobsoniidae (Coleoptera) from China with description of a new species of Sarothrias Grouvelle, ZooKeys 496, pp. 53-60 : 54-57

Taxon classification Animalia Coleoptera Jacobsoniidae

Sarothrias sinicus Bi & Chen sp. n. Figs 1-4, 5

Type material.

Holotype: male, "China: Xizang, Motuo / Baricun / 2014.VII.27 1850 m / leg. Wen-Xuan Bi" [white label printed]. The holotype was deposited in the Insect Collection of Shanghai Normal University, Shanghai, China (SNUC).

Diagnosis.

This new species can be separated from most congeners by the elytra, which are predominantly shiny, and elytral row 5 unimpressed; the pronotum is devoid of squamiform setae. It differs from Sarothrias hygrophilus Pal by the elytra, with row 1 largely represented by fine punctures, row 2 interrupted by punctures after basal quarter, and with supplementary series (s1) between rows 3 and 4; the pronotum has secretions on the lateral margins instead of on the side below the protrusions. It also resembles Sarothrias papuanus Ślipiński but can be easily distinguished by the elytra, bearing four squamiform setae in the distal half of row 2, row 3 merging with row 2 and with s1 between rows 3 and 4; the pronotum is devoid of secretions.

Description.

Male (Figs 1-3). Body length 2.20 mm, elongate, convex, dark-brown, dorsal surface largely shiny except whitish secretions in parts of pronotum and elytra; legs, excluded tarsi, pubescent and covered with yellowish secretions except two narrow longitudinal shiny band at both sides of femora and tibiae, tarsi brown; wings fully developed.

Head broader than long, width across eyes 0.45 mm, clypeus smooth, rounded anteriorly, fronto-clypeal suture clearly visible; frons slightly broad anteriorly with sides moderately raised, sparsely and distinctly setigerous punctured; eyes large, rounded, nearly as long as half of head length, coarsely facetted. Antenna length 0.88 mm, scape slightly elongate, antennomeres 2-11 transverse, with secretions on antennomeres 1-8, squamiform setae at apex of scape and on antennomeres 2-10 and normal setae on antennomeres 9-11.

Pronotum length 0.67 mm, width 0.48 mm, subparallel-sided, widest near middle; anterior margin rounded; disc with a shallow median groove, extending from the anterior one-fifth to little above base, slightly broad posteriorly; punctures on disc of similar size, shape and distribution to those on head; median groove, lateral margins and one-sixth of pronotal base with secretions. Scutellum invisible.

Elytra length 1.38 mm, width 0.79 mm, fusiform, widest slightly after middle; basal transverse bulge well developed, with subbasal band of secretions on which three subbasal depressions on each elytron, each depression with one squamiform setae posteriorly. Each elytron with striae or fine puncture forming 8 rows and 3 supplementary series (Fig. 4) of which 6 rows and 2 supplementary series are visible in dorsal view; rows 1 to 3 impressed at basal quarter and continued as a row of fine punctures, row 2 once again impressed after middle and connected with row 1 subapically, row 3 joined row 2 at apical one-third, rows 4 and 5 represented by fine punctures and disappearing anterior to apical one-third, row 6 largely impressed but intercepted by single puncture at basal one-third, rows 7 and 8 impressed, of which the former extending subapically and the latter starting at basal quarter and extending half of elytra length; three supplementary series (s1, s2, s3) represented by fine punctures, of which s1 present between rows 3 and 4 which starting at basal quarter and joined row 4 anterior to basal half, s2 (=s in Poggi 1991) present between rows 5 and 6 which starting at basal one-sixth and ending subapically, s3 separate from row 7 at basal two-fifths and ending subapically between row 6 and 7; apical half of row 2 and entire length of row 6 with secretions, of which the former secretionary row with four squamiform setae asymmetrically arranged.

Prosternum and mesoventrite largely covered with secretions. Metaventrite covered with the same secretions after mesocoxal insertions (cavities) and between metacoxal insertions, other parts shiny with very sparser and fine punctures; with deep median impression in apical half which with rounded sides and not delimited by lateral ridges. Legs moderately long, tarsi 3-segmented.

Ecological notes.

Adult Sarothrias have been collected in leaf litter and rotten wood, but the larvae are as yet unknown ( Lawrence and Leschen 2010). The only specimen of the new species was collected by beating a branch with dead leaves on the way from Baricun (= Bari village) to Renqinbeng (= Renqinbeng Temple), Motuo, Xizang at altitude of 1850 m (Fig. 5). The vegetation types are subtropical evergreen broadleaf forest which has been well protected, although slightly disturbed by locals by grazing. A variety of staphylinids, endomychids and cerambycids were collected at the same time. Another mysterious termitophilous lucanid, Penichrolucanus cryptonychus (Zhang, 1988), which is located in the same area and known only from its original description shares a similar generic distribution with Sarothrias .

Distribution.

China: Xizang (Tibet) Autonomous Region, Motuo County.

Etymology.

The new species is named after the country of the type locality.