Exochomoscirtes arunachalensis, Ruta & Yoshitomi, 2010

Ruta, Rafał & Yoshitomi, Hiroyuki, 2010, Revision of the genus Exochomoscirtes Pic (Coleoptera: Scirtidae: Scirtinae) 2598, Zootaxa 2598 (1), pp. 1-80 : 74-75

Exochomoscirtes arunachalensis sp. nov.

( Figs. 14F , 61 )

Type material. Holotype, male ( NHM): “NE INDIA, ARUNACHAL PR. / 8 km S Jamiri- SESSA vicinity / 27°07’–09’ N 92°34’ E, 350m / L. Dembický leg., 25.v.–4.vi.2005 ” [printed label]; “BMNH {E} / 2006-48 / L. Dembicky ” [printed label].

Diagnosis. Inconspicuous brownish-black species with slightly lighter sutural portion of elytra. It differs from the other species of the genus in having a relatively large, well developed penis and a wide mesal process of the tegmen and the parameres with peculiar hook-like structures at their apices.

Description. Holotype, male. Body oval, TL/EW 1.3, somewhat flattened, covered with black setae. Head brownish black, pronotum dark brown with brownish sides, elytra black with brown suture. Ventrum brown, legs yellowish-brown with the exception of metafemora which are brownish-black. Mouthparts and antennae yellowish, antennae darkening apically.

Head covered with small and relatively sparse punctures, punctures separated by ca. 2.0 diameters. Eyes big, protuberant; head 1.7 X wider than interocular space. Antennae filiform, apical antennomere missing in the holotype. Antennomeres 2 and 3 of subequal lengths, antennomere 3 slightly shorter, antennomere 4 as long as antennomeres 2 and 3 combined. Palpomeres of maxillary palpi moderately widened.

Pronotum slightly convex, covered with subtle punctation, punctures small and shallow, separated by ca. 2.0–3.0 diameters, anterolateral corners obtuse, slightly projecting anteriorly; lateral margins straight; posterolateral corners almost right-angled; base of pronotum subtrapezoidal, with complete groove along basal margin; PW/PL 2.4. Scutellum punctured as on pronotum, equilaterally triangular. Angle between pronotum and elytra not marked in dorsal outline.

Elytra oval, lateral margins not explanate, without traces of longitudinal ridges, widest a bit before the middle, punctation stronger than on pronotum, punctures separated by ca. 1.0–1.5 diameters; humeri well marked; EL/EW 1.2; EL/PL 4.5; EW/PW 1.5.

Legs moderately long. Hind tibial spurs well developed, dorsal one slightly curved, unmodified, slightly shorter than tarsomere 1, twice as long as ventral one; ventral spur slightly curved.

Apex of ventrite 5 truncate.

Sternite 9 (L 0.55, W 0.27) rectangular, with sparse setae at apical margin; tergite 8 (L 0.67, W 0.35) with basally diverging apodemes and a row of dense setae on apical margin; tergit 9 (L 0.75, W 0.30) with strongly reduced apical portion and long apodemes; tegmen (L 0.85, W 0.50) with long, straight, apically hooked parameres and large mesal process which widens apically; penis (L 0.66, W 0.17) large, apical portion of trigonium curved ventrad.

Female unknown.

Measurements. Male (n = 1): TL 3.10, PL 0.65, PW 1.55, EL 2.90, EW 2.35.

Distribution. Arunachal Pradesh, NE India.

Etymology. After Arunachal Pradesh, where the holotype was collected.

Figures

FIGURE 14. Habitus illustrations of Exochomoscirtes. A) E. dilaticornis sp. nov., female; B) E. pectinatus sp. nov.; C) E. longispinus sp. nov.; D) E. nipponicus sp. nov.; E) E. nahangensis sp. nov.; F) E. arunachalensis sp. nov.; G) E. meghalayensis sp. nov. Scale bar = 2.0 mm.

FIGURE 61. Exochomoscirtes arunachalensis sp. nov., male. A) sternite 9; B) tergite 8; C) tergite 9; D) tegmen; E) paramere, detail; F) penis. Scale bar = 0.5 mm (with the exception of fig. E).