Lobrathium rutilum, Solodovinikov, Xiao-Yan Li Alexey & Zhou, Hong-Zhang, 2013

Solodovinikov, Xiao-Yan Li Alexey & Zhou, Hong-Zhang, 2013, Four new species of the genus Lobrathium Mulsant & Rey (Coleoptera: Staphylinidae: Paederinae) from China, Zootaxa 3635 (5), pp. 569-578 : 573-574

2. Lobrathium rutilum sp. n.

( Figs. 2 A–E, 5B).

Type material. Holotype, 3, CHINA: Hubei Province, Shennongjia Gangou, 1610 m, 1–8. VIII. 1998, leg. Xiaodong Yu (IZCAS).

Description. Length: 9.20 mm; width: 1.25 mm. Body parts (all in mm): HL 1.42; AL 2.80; PL 1.33; ELL 1.36; HW 1.23; PW 1.15; ELW 1.25; ABW 1.09.

Body, including antennae and legs, brownish red with luster.

Head with distinct posterior angles, rather parallel-sided, with HL/HW = 0.9, vertex slightly convex, anterolateral margin narrow. Eyes rather small and even; HL/EL = 14.2, diameter of eye shorter than gena and much shorter than temple (gena eye temple = 0.29: 0.10: 1.03 mm). Vertex and middle front smooth and glossy with punctures sparse but large.

Pronotum oblong with PL/PW = 1.2 and punctation consisting of punctures larger than such on head. Scutellum U–shaped, longer than wide, surface without luster but with larger setiferous punctation.

Elytra as long as wide, ESL/ELL = 0.7 with uneven surface, epipleural ridge absent in the basal fifth of elytral length, punctures dense and coarse, diameter of punctures similar but denser than punctures on pronotum, each puncture with an oblique yellowish brown seta, intervals between punctures larger than diameter of a puncture. Hind wings rather reduced, shorter than elytra.

Abdomen widest at segment VI (4th visible), narrower than head, pronotum or elytra; setiferous punctures on tergites fine and dense, each bearing black setae, punctures denser laterally; punctures on sternites of the same size, with pale setae. Middle areas of sternites III –VI slightly convex with sparse punctures.

Aedeagus ( Figs. 2 C–E) slightly asymmetrical, length/width = 2.5. Dorsal plate of median lobe small, of irregular shape, gradually broadened posteriad, with sinuate apex. Ventral process strongly sclerotized and straight ( Figs. 2 D, E).

Male secondary sexual characters: sternite VII with slightly depressed middle area and shallowly emarginated posterior margin; hind margin of sternite VIII ( Fig. 2 A) with deeply rounded and broad notch and rather dense, hard hairs and, medially, with dense thorns; sternite IX ( Fig. 2 B) with base and setiferous part symmetrical.

Females unknown.

Etymology. The specific epithet is the Latin adjective rutilum (brownish red) that refers to the coloration of this species.

Remarks. This new species can be easily distinguished from all other species of Lobrathium by the following characteristics: 1) robust, long and brownish red body; 2) the posterior part of elytra without color spots; 3) straight and slender ventral process of the aedeagus ( Figs. 2 D–E). Although L. rotundiceps (Koch) also has red body and elytra without color spots, its head is about as long as wide and rounded in dorsal view (Zheng 1988; Assing 2012). The new species, on the contrary, has quadrate-like head in dorsal view that is distinctly longer than wide.

Distribution. The only known specimen of Lobrathium rutilum sp. n. was found in the northwest of Hubei Province in Shennongjia Nature Reserve in the mountains with well developed forest and grass vegetation. It was collected in August by pitfall trap with the mixture of sugar, vinegar, water and alcohol at the altitude of 1600 m.

Figures

FIGURE 2. Lobrathium rutilum sp. n. from Hubei. A. sternite VIII, male; B. sternite IX, male; C. apex of aedeagus, dorsal view; D. aedeagus, lateral view; E. aedeagus, ventral view. Scale = 0.5 mm.