Gynaecoserica schima, Ahrens & Fabrizi, 2009

Ahrens, Dirk & Fabrizi, Silvia, 2009, A review of the genus Gynaecoserica Brenske, 1896 (Coleoptera, Scarabaeidae, Sericini), Journal of Natural History 43 (25 - 26), pp. 1505-1584 : 1575-1576

Gynaecoserica schima sp. nov.

( Figures 5G–J , 9A )

Type material examined

Holotype. Ƌ “N. Burma: Adung Valley . 6.v.1931 6,000 ft. F. Kingdon Ward B.M. 1932-196./ On flowers of Schima / 483 Sericini Asia spec.” ( BMNH) . Paratypes. 2 ♀♀ – same data as holotype ( BMNH, CA) .

Description

Length 5.7 mm, length of elytra 4.0 mm, width 3.1 mm. Body oblong, reddish brown, frons darker, antenna yellowish brown, dorsal surface dull, sparsely setose.

Labroclypeus subrectangular, widest at base, lateral margins in basal half subparallel, strongly curved and convergent to the strongly rounded anterior angles, lateral border and ocular canthus producing a distinct blunt angle, margins weakly reflexed, anterior margin very shallowly sinuate medially; surface weakly convex medially and moderately shiny, finely and very densely punctate, distance between punctures less than their diameter, with a few coarser punctures behind anterior margin bearing long, erect setae; frontoclypeal suture indistinctly incised, medially moderately curved; smooth area in front of eye approximately as wide as long; ocular canthus short and moderately slender, finely and densely punctate, with a fine terminal seta. Frons shiny, posteriorly dull, with fine and irregularly dense punctures, beside eyes and behind frontoclypeal suture with a few erect setae. Eyes rather small, ratio of diameter: interocular width 0.5. Antenna yellow, in holotype only antennomere 1 and 2 present. Mentum weakly elevated and flattened anteriorly.

Pronotum widest at base, lateral margins in basal half straight and weakly convergent anteriorly, in middle slightly curved and in anterior half straight and convergent anteriorly, anterior angles moderately produced and sharply pointed, posterior angles blunt, anterior margin convexly produced medially, with a fine marginal line, basal margin without marginal line; surface with moderately dense and fine shallow punctures, each puncture bears a minute seta; anterior and lateral borders thinly setaceous; hypomeron distinctly margined at base but not ventrally produced. Scutellum long and narrow, triangular, with fine, dense punctures, on base medially smooth, microscopic setae present in the punctures.

Elytra oblong, widest in apical third, striae distinctly impressed and finely densely punctate, intervals moderately convex, with fine, sparsely scattered punctures concentrated along the striae, punctures with microscopic setae only, but odd intervals with single white scale-like adjacent setae; interior apical angle of elytra with a robust seta; epipleural edge fine ending at the strongly curved external apical angle of elytra, epipleura densely setaceous, apical border without short microtrichomes.

Ventral surface dull, with fine and moderately dense punctures, sparsely setose, metacoxa only laterally with a few strong adjacent setae; each abdominal sternite with indistinct transverse row of coarse punctures bearing short setae between fine, dense punctation, penultimate sternite apically without a shiny smooth sclerotized border, last sternite medially almost as long as penultimate one. Mesosternum between mesocoxae as wide as mesofemur, with irregularly scattered very strong setae. Ratio of length of metepisternum: metacoxa: 1: 1.28. Pygidium moderately convex, basal portion shiny and almost smooth, apical portion dull, coarsely but sparsely punctate, with smooth midline and with a few erect long and short setae.

Legs slender and moderately long; femora dull, with two longitudinal rows of setae, finely and sparsely punctate; metafemur shiny and moderately and densely punctate, sharply margined anteriorly and without a submarginal serrate line, posterior margin weakly convex and glabrous, its external part only weakly widened in apical half and not serrate, internally very finely serrate, with a few long setae. Metatibiae including tarsi lacking in holotype. Protibia moderately long, bidentate, protarsal claws symmetrical.

Aedeagus shown in Figure 5 (G–J).

Variation

Length 5.2–5.7 mm, length of elytra 3.8–4.0 mm, width 3.1–3.2 mm. Female: antennal club with three antennomeres, distinctly shorter than the remaining antennomeres combined. Pronotum at the sides with white adjacent setae and medially with numerous setae bent backwards. Metatibia slender and moderately long, uniformly widened toward apex, ratio width: length 1: 3.1, dorsally moderately edged, in basal half longitudinally convex, with two groups of spines, basal one at one-third, apical one at two-thirds of metatibial length, basally with a few single, fine spines in the punctures; external face longitudinally convex, with moderately dense and coarse punctures, glabrous; ventrally edged and serrate, with three strong equidistant spines, internal face finely sparsely punctate and smooth, apex interiorly near tarsal articulation sharply and deeply truncate. Tarsomeres dorsally glabrous and impunctate, ventrally with sparse, short setae; metatarsomeres ventrally with a strongly serrate ridge, beside which is a fine longitudinal carina, first metatarsomere distinctly shorter than the following two tarsomeres combined and one third longer than the upper tibial spur.

Diagnosis

Significant characters of the male antennal club are not available for examination, so G. schima sp. nov. may be differentiated from species with similar habitus, G. pellecta , G. amara sp. nov., G. alma sp. nov. and G. obliqua sp. nov., and the species described immediately below, only by the shape of the parameres, which are very long, slender and curved ventrally.

Etymology

Named according to the tree genus Schima, from which the type specimen was collected.

Figures

Figure 5. (A–C) Gynaecoserica obliqua sp. nov. (holotype), (D–F) G. rostrata sp. nov. (holotype), (G–J) G. schima sp. nov. (holotype), (K–M) G. seinghkuensis sp. nov. (holotype), (N–P) G. vogleri sp. nov. (holotype), (Q–S) G. ziyardamensis sp. nov. (holotype). (A, D, G, K, N, Q) Aedeagus, left side lateral view; (C, F, J, M, P, S) aedeagus, left side lateral view; (B, E, I, L, O, R) parameres, dorsal view; (H) parameres, subdorsal view. Scale bars 0.5 mm.

Figure 9. Distribution of Gynaecoserica species (A, upper panel; B, lower panel). “?” in (B) indicates the not precisely localized collecting locality of G. gisionensis sp. nov. in Vientiane province in Laos.