Megatyrus femoralis Yin and Li

Yin, Zi-Wei & Li, Li-Zhen, 2014, New species and new record of Megatyrus Hlaváč & Nomura (Coleoptera: Staphylinidae: Pselaphinae) from Asia, Zootaxa 3815 (3), pp. 435-440 : 436-438

Megatyrus femoralis Yin and Li , new species

( Figs 1–2 )

Type material (1 ♂, 2 ♀♀). Holotype: ♂, NEPAL: labeled ‘E. NEPAL: KOSI, Val. Arun ss/Num, 1,100 m, 21.IV.84, Löbl-Smetana / Holotype [red] ♂, Megatyrus femoralis sp. n., det. Yin & Li, 2014, MHNG’. Paratype: 2 ♀♀, NEPAL: same collection data as the holotype, each with a paratype label similar to that of holotype except ‘ Paratype [yellow] ♀’.

Diagnosis. Length 3.59–3.63 mm. Male with first antennomeres protruding on lateral margins; profemora thickened, apical portion of protibiae protuberant; mesotrochanters and metacoxae protuberant on ventral margins; aedeagus stout, with median lobe obliquely truncate at apex, endophallus composed of three sclerites. Female with transverse genital complex.

Description. Male ( Fig. 1 A). Length 3.63 mm. Head longer than wide, HL 0.81 mm, HW 0.75 mm; eyes each composed of about 45 facets; venter with tuberculate lateral projections ( Fig. 2 D); maxillary palpi ( Fig. 2 C) with palpomeres II–IV each lengthily pedunculate in basal halves, apical halves enlarged; palpomeres IV lacking palpal cone; scapes ( Fig. 2 B) short and thick, angularly projecting on lateral margins; clubs ( Fig. 2 A) simple, formed by enlarged three apical antennomeres. Pronotum longer than wide, PL 0.80 mm, PW 0.73 mm, lateral margins nearly parallel. Elytra wider than long, EL 1.06 mm, EW 1.52 mm. Short metaventral process ( Fig. 2 E) present, rounded apically. Profemora ( Fig. 2 F) thickening through length, protibiae ( Fig. 2 G) curved mesally at apical fourth, and strongly protruding ( Fig. 2 H) at apices; mesotrochanters ( Fig. 2 I) with large triangular ventral projection; ventral margins of metacoxae ( Fig. 2 J) greatly expanded, expansion curved at apices. Abdomen broad at base and narrowing apically, AL 0.96 mm, AW 1.44 mm; tergite IV (first visible tegite) with median discal carina extending through tergal length, tergites V–VI successively shorter, length of tergite VII subequal to that of tergite IV, tergite VIII ( Fig. 2 K) transverse, narrowing from middle toward apex, posterior margin nearly truncate, slightly wavy; sternite VIII ( Fig. 2 L) transverse, posterior margin shallowly and roundly concave at middle, sternite IX ( Fig. 2 M) semi-membranous. Aedeagus ( Figs 2 N–P) length 0.60 mm; median lobe short and broad, obliquely truncate at apex; parameres largely reduced; endophallus composed of two short, thick, and one long, slender sclerites.

Female ( Fig. 1 B). Scapes simple; antennal clubs less distinct than those of male; maxillary palpi identical to those of male. Each eye composed of about 40 facets. Profemora, protibiae, mesotrochanters, and metacoxae simple; lacking metaventral processes. Tergite VIII ( Fig. 2 Q) with lateral margins prolonged posteriorly, posterior margin broadly and roundly concave at middle; sternite VIII ( Fig. 2 R) transverse, posterior margin slightly protruding medially. Genital complex ( Fig. 2 S) width 0.47 mm, transverse, with pair of membranous lateral lamina.

Measurements of female: BL 3.59–3.69 mm, HL 0.84–0.85 mm, HW 0.73–0.74 mm, PL 0.73–0.77 mm, PW 0.69–0.73 mm, EL 0.88–0.90 mm, EW 1.38–1.41 mm, AL 1.14–1.17 mm, AW 1.41–1.52 mm.

Comparative notes. Males of Megatyrus femoralis can be quickly separated from those, if known, of all congeners by the distinctive thickened profemora, and by the greatly protruding apical portion of the protibiae. The forms of the maxillary palpi, metaventral processes, mesotrochanters, metacoxae, and aedeagus are useful in case other species are found near the type locality. Females of M. femoralis can be identified by association with the male, and can be separated from those Megatyrus species based only on female material by the forms of maxillary palpi, tergite VIII, sternite VIII, and the genital complex.

Distribution. East Nepal: Koshi. The present record extends the known range of Megatyrus about 1,200 km to the west.

Etymology. The specific name refers to the male thickened femora, which is species characteristic.

Figures

FIGURE 1. Habitus of Megatyrus femoralis. A. Male. B. Female. Scales (mm): 1.0.

FIGURE 2. Diagnostic characters of Megatyrus femoralis (A – P. Male. Q – S. Female.). A. Antennal club. B. Scape. C. Maxillary palpus. D. Head, in lateral view. E. Metaventral process, in lateral view. F. Profemur. G. Protibia. H. Apical portion of protibia. I. Mesotrochanter and mesofemur. J. Metacoxa, metatrochanter, and metafemur. K, Q. Tergite VIII. L, R. Sternite VIII. M. Sternite IX. N. Aedeagus, in dorsal view. O. Same, in lateral view. P. Same, in ventral view. S. Genital complex. Scales (mm): A, D, F, G, I, J = 0.3; C, K, L, N, O, P, Q, R = 0.2; B, E, H, M, S = 0.1.