Crataraea myrmecophila, Assing, 2014

Assing, V., 2014, A Crataraea species associated with Formica chinensis (Coleoptera: Staphylinidae: Aleocharinae), Linzer biologische Beiträge 46 (1), pp. 525-530 : 526-529

Crataraea myrmecophila nov.sp. ( Figs 1-11 )

T y p e m a t e r i a l: Holotype [with two Formica workers attached to the pin]: "China: Qinghai Prov. [CH11-09a], Daban Shan , 62 km NNW Honggu, creek valley, 2236 m, Picea , Populus, Betula forest, 26°51'28.4''N, 102°37'07.6''E, / Formica nest, sifted [ CH 11-09a], 26.VI.2011, leg. M. Schülke, Formica chinensis Wheeler, 1913, det. B. Seifert [Nestprobe] / Holotypus Crataraea myrmecophila sp.n. det. V. Assing 2014" (cAss) . Paratypes: 2, 3 [each of them with a Formica worker attached to the pin]: same data as holotype (cSch, cAss) ; 5: same data as holotype, but "[ CH 11-9d] ... 29.VI.2011 " (cSch, cAss); 1: same data as holotype, but "[ CH 11- 9g] ... 15.VII.2011 " (cSch) .

E t y m o l o g y: The specific epithet (adjective) alludes to the hypothesized myrmecophily of this species.

D e s c r i p t i o n: Body length 2.7-3.6 mm; length of forebody 1.2-1.5 mm. Habitus as in Fig. 1 . Coloration: head blackish-brown to blackish; pronotum and elytra brown to dark-brown, the latter with the posterior sutural portion often somewhat paler; abdomen dark-brown, with the posterior margins of the segments reddish; legs and antennae darkyellowish.

Head ( Fig. 2 ) weakly transverse; punctation sparse and extremely fine, barely noticeable in the microreticulation ( Fig. 8 ). Eyes weakly convex, slightly shorter than postocular region in dorsal view. Antenna ( Fig. 2 ) incrassate apically; antennomeres IV-X strongly transverse, IV more than 1.5 times as wide as long, V-X at least twice as wide as long.

Pronotum ( Fig. 2 ) strongly transverse, approximately 1.5 times as broad as long and 1.4 times as broad as head; punctation sparse and very fine; interstices with shallow, but distinct microreticulation ( Fig. 9 ).

Elytra ( Fig. 2 ) approximately as long as pronotum; punctation much more distinct than that of head and pronotum ( Fig. 3 ); interstices with shallow microsculpture. Hind wings fully developed. Metatarsomere I slightly longer than the combined length of II and III.

Abdomen narrower than elytra; punctation moderately dense and moderately fine, rather sparse on tergites VII-VIII; tergites III-V shallowly impressed anteriorly; posterior margin of tergite VII with palisade fringe; posterior margin of tergite VIII weakly convex in both sexes.

: sternite VIII ( Fig. 10 ) distinctly transverse, posterior margin convexly produced and with long marginal setae in the middle; median lobe of aedeagus ( Figs 4-6 ) slightly more than 0.45 mm long, somewhat angled ventrally in lateral view.

: sternite VIII ( Fig. 11 ) distinctly transverse, posterior margin convex (except for the weakly concave middle) and with row of short modified marginal setae; spermatheca as in Fig. 7.

C o m p a r a t i v e n o t e s: The new species is easily distinguished from C. suturalis by numerous characters, particularly the smaller body, the smaller eyes, the much less pronounced microreticulation of the head, pronotum, and abdomen, the more transverse antennomere III, the more transverse pronotum, the posteriorly less strongly and more broadly produced male sternite VIII, the differently shaped median lobe of the aedeagus, and by the longer and nearly straight proximal portion of the spermathecal capsule. For illustrations of the habitus and the sexual characters of C. suturalis see figures 36 and 192a-c in KLIMASZEWSKI et al. (2013). According to EPPELSHEIM (1888), C. solskyi from Uzbekistan has reddish elytra, a reddish abdominal apex, an extremely densely punctate and consequently nearly matt forebody, and antennae of different morphology (antennomere IV as long as broad; antennomeres V-X weakly transverse).

D i s t r i b u t i o n a n d n a t u r a l h i s t o r y: Crataraea myrmecophila is the first representative of the genus to be recorded from the East Palaearctic region east of Middle Asia. The type locality is situated in the Daban Shan in Qinghai province, China. The specimens were exclusively sifted from nests of Formica chinensis in a mixed forest at an altitude of approximately 2340 m. The fact that the species was found in several ant nests, but was absent from sifted leaf litter samples in the same locality suggests that it is actually associated with the ant and not an accidental guest.

Figures

Figs 1-7: Crataraea myrmecophila nov.sp.: (1) habitus; (2) forebody; (3) right elytron; (4-5) median lobe of aedeagus in lateral view; (6) ventral process of median lobe in ventral view; (7) spermatheca. Scale bars: 1-2: 1.0 mm; 3-7: 0.2 mm.

Figs 8-11: Crataraea myrmecophila nov.sp.: (8) vertex; (9) median portion of pronotum; (10) male sternite VIII; (11) female sternite VIII. Scale bars: 0.1 mm.