Horaeomorphus xiweii Zhou & Yin, 2018

Zhou, De-Yao & Yin, Zi-Wei, 2018, A new species and a new record of Horaeomorphus Schaufuss (Staphylinidae: Scydmaeninae: Glandulariini) from China, Zootaxa 4462 (1), pp. 141-144 : 141-144

Horaeomorphus xiweii Zhou & Yin , sp. nov. ( Figs 1 , 2D‒E )

Type material. Holotype: CHINA: ♂, ‘ China: Yunnan, Tengchong County (D ṖH), Diantan Town (AEẘffi), Dadong-shan-he (IJḂƜÑ), 25°31'42.67"N, 98°22'54.24"E, 2000m, 2016. vii.4, Zi-Chun Xiong leg’ ( SNUC). Paratypes: CHINA: 2 ♀♀, same label data as the holotype ( SNUC).

Diagnosis of male. Body moderately large and strongly elongate; pronotum with a row of five dorsal pits connected by a shallow groove; metatrochanter unmodified; aedeagal endophallus strongly asymmetric.

Description. Male. BL 2.68 mm; body ( Fig. 1A ) moderately large, convex, dark reddish-brown, legs and palpi slightly lighter.

Head broadest at large, finely faceted and moderately convex eyes, HL 0.40 mm, HW 0.53 mm; tempora rounded, about as long as length of eye in dorsal view; vertex strongly transverse and weakly convex, with pair of small but distinct pits located near posterior margins of supra-antennal tubercles; frons weakly convex; supra-antennal tubercles strongly raised. Punctation on vertex and frons sparse, small but distinct; setae moderately long, sparse. Antennae ( Fig. 1H ) short, AnL 1.21 mm, relative lengths of antennomeres: 1.36: 1.0: 1.36: 1.27: 1.09: 1.0: 1.0: 1.0: 1.18: 1.09: 1.91.

Pronotum longer than wide, widest slightly in front of middle, PL 0.74 mm, PWm 0.61 mm, PWb 1.50 mm; anterior and lateral margins rounded, sides posteriorly nearly straight up to sub-basal constriction; base with row of five dorsal pits connected by shallow antebasal groove, and with one pair of lateral impressions each located laterally in the constriction. Punctation on disc distinct, punctures at middle separated by spaces about as wide as 1‒1.5 × diameters of puncture; setation moderately long, suberect.

Elytra elongate, more convex than pronotum, distinctly impressed dorsally at middle and widest at about anterior third. EL 1.53 mm, EW 0.95 mm, EI 1.62. Humeral calli distinct. Punctures fine, more distinct than those on pronotum, sharply marked and separated by spaces 1‒2 × as wide as puncture diameters; setation moderately dense. Hindwings fully developed.

Aedeagus ( Fig. 1B‒D ) slender, AeL 0.54 mm; endophallus ( Fig. 1E‒F ) strongly asymmetric, with curved axial component protruding from distal sclerotized complex surrounded by pair of asymmetric lateral lobes with their roots connected by membranous structure; apical third covered by broad hexagonal structure with deeply emarginate apical margin, with transverse trapezoidal sclerite having its apical margin emarginated; parameres ( Fig. 1G ) slender, slightly shorter in length to median lobe, each with three apical setae and three to four subapical setae.

Female. Similar to male, but with smaller body; mesotibiae with apical half of inner margin slightly less curved than those in males. BL 2.60‒2.63 mm, HL 0.40 mm, HW 0.52‒0.53 mm, AnL 1.20 mm, relative lengths of antennomeres: 1.5: 1.0: 1.4: 1.3: 1.2: 1.1: 1.1: 1.1: 1.3: 1.2: 2.3. PL 0.73‒0.74 mm, PWm 0.59 mm, PWb 0.48‒0.49 mm; EL 1.47‒1.49 mm, EW 0.93 mm, EI 1.59‒1.61, spermatheca ( Fig. 1J ) oval, SpL 0.11 mm, with moderately large accessory gland, ductus spermathecae with its insertion to spermatheca covered by corneous sclerite; bursa copulatrix (shown in Fig. 1I ) contains transverse sclerite, with its two ends connected by arched structure.

Comparative notes. Among all Horaeomorphus species, H. xiweii is most similar to H. biwenxuani Zhou & Zhang from Xizang (= Tibet) by sharing an asymmetric aedeagal endophallus with a similarly curved central axial component that is surrounded by a pair of lateral acute sclerites. The new species can be readily separated from H. biwenxuani by the relatively much less elongate antennomeres II‒V, presence of five pronotal antebasal pits (three in H. biwenxuani ), simple male metatrochanters (in H. biwenxuani the metatrochanter is subtriangular, with the distal edge produced into a short spine), and the endophallus with a dorsal hexagonal sclerite (sclerite absent in H. biwenxuani ).

Distribution. Southwest China: Yunnan.

Etymology. The specific epithet is dedicated to Wei Xi, a close friend of Zi-Chun Xiong who collected the type series.

Bionomics. The adults were collected from under bark of a dead pine ( Fig. 2E ) in a mixed forest ( Fig. 2D ).

Figures

FIGURE 1. Horaeomorphus xiweii sp. n. A. Male, dorsal habitus. B–D. Aedeagus, in ventral (B), lateral (C), and dorsal (D) view. E. Endophallus, enlarged, in dorsal view. F. Same, schematic. G. Apical portion of paramere. H. Right antenna of male, in dorsal view. I. Female terminalia, in dorsal view. J. Spermatheca, in lateral view. K–L. Mesotibiae of male (K), and female (H). Abbreviations: bc, bursa copulatrix.

FIGURE 2. A. dorsal habitus of Horaeomorphus solodovnikovi from Yunnan. B–C. Aedeagus, in ventral (B), and lateral (C) view. D– E. Surrounding environment (D), and habitat (E) where H. xiweii was collected.