Gynaecoserica rostrata, 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 : 1573-1575

publication ID	https://doi.org/ 10.1080/00222930902968809
persistent identifier	https://treatment.plazi.org/id/0399C459-DB6E-6F1F-FDAC-FE575AB60F16
treatment provided by	Felipe
scientific name	Gynaecoserica rostrata
status	sp. nov.

Treatment

Gynaecoserica rostrata sp. nov.

( Figures 5D–F View Figure 5 , 9A View Figure 9 )

Type material examined

Holotype. Ƌ “ Burma ( Myanmar) SW Shan state Taunggyi J. Rejsek 1.- 18.6.1997 ” ( BMNH). Paratypes. 1 Ƌ “ Burma ( Myanmar) SW Shan State; Taunggyi; 1.-18.VI.1997; J. Kaláb leg.” ( CA), 1 Ƌ “ Thai, N, Mae Hong Son prov. , SE of Soppong, 1500 m, 19°27¢N, 98°20¢E, 23–27.v.1999, M. Riha leg.” ( TICB).

Description

Length 4.0 mm, length of elytra 2.5 mm, width 2.3 mm. Body oblong oval, surface dark reddish brown, elytra partly yellowish, dorsal surface except head dull and erectly setose.

Labroclypeus only slightly wider than long, widest at base, lateral margins basally weakly curved, anteriorly very strongly curved and strongly convergent to strongly rounded anterior angles, lateral border and ocular canthus producing a distinct blunt angle, margins weakly reflexed, anterior margin straight; surface medially convex, finely and densely punctate, distance between punctures a little wider than their diameter, with a few coarse punctures behind anterior margin each bearing an erect seta; frontoclypeal suture feebly incised and medially weakly curved; smooth area in front of eye approximately 1.5 times as wide as long; ocular canthus short and slender, smooth, with a fine terminal seta. Frons shiny, only posteriorly dull, with fine, moderately dense punctures, sparsely erectly setose. Eyes small, ratio of diameter: interocular width 0.52. Antenna yellow, with 10 antennomeres; club with four antennomeres, club as long as the remaining antennomeres combined, sixth antennomere weakly transversely produced. Mentum weakly elevated and flattened anteriorly.

Pronotum moderately wide, widest at base, lateral margins weakly curved and weakly convergent anteriorly, in anterior half more strongly convergent towards the strongly produced and sharp anterior angles, posterior angles blunt, anterior margin strongly convexly produced medially, with a broad smooth marginal line, basal margin without marginal line; surface with dense and coarse punctures, with microscopic setae in punctures and a few longer robust setae laterally only; anterior and lateral borders setaceous; hypomeron distinctly margined at base but not ventrally produced. Scutellum short and triangular, with very fine, dense punctures, on base medially smooth, microscopic setae present in the punctures.

Elytra moderately long and oval, widest at middle, second and third interval as well apical declivity yellowish brown, striae feebly impressed, finely and densely punctate, intervals almost flat, with fine and moderately dense punctures concentrated along the striae, punctures with fine microscopic setae, additionally all intervals along the striae with single coarse punctures each bearing a robust white erect seta, interior apical angle of elytra with a strong 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 with a shiny smooth sclerotized bor- der, which is one-sixth as long as sternite, last sternite medially a little shorter than the penultimate one. Mesosternum between mesocoxae as wide as mesofemur, with irregularly scattered very strong setae. Ratio of length of metepisternum: metacoxa 1: 1.52. Pygidium moderately convex medially, coarsely and densely punctate, with smooth midline, with moderately dense robust light setae.

Legs robust and short; femora dull, with two longitudinal rows of setae, finely and sparsely punctate; metafemur shiny, sharply margined anteriorly and without a submarginal serrate line, posterior margin weakly convex and glabrous, ventrally only weakly widened in apical half and not serrate, dorsally finely serrate, with short setae. Metatibia moderately slender and moderately long, medially convexly widened, widest at middle, ratio width: length: 1: 3.0, dorsally weakly carinate, 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, almost smooth, with very sparse and coarse punctures on ventral portion only, glabrous; ventrally edged and serrate, with three strong, equidistant spines, internal face not 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 as long as the following two tarsomeres combined and twice as long as the upper tibial spur. Protibia very short, bidentate, protarsal claws symmetrical.

Aedeagus shown in Figure 5 View Figure 5 (D–F).

Variation

Length 4.0– 4.3 mm, length of elytra 2.5–2.7 mm, width 2.3–2.4 mm. Coloration of elytra variable, also uniformly brown. Density of pilosity of pronotum and elytra may vary considerably, in paratypes it is much denser (similar to G. hirsuta ), pilosity may be erased (as in the holotype). Female unknown.

Diagnosis

Gynaecoserica rostrata sp. nov. is externally similar to G. hirsuta sp. nov. and G. nahangensis sp. nov. It may be differentiated from G. nahangensis by the antennal club of the male, which has four antennomeres only, and by the apically hooked right apophysis of the phallobase. The latter feature also distinguishes it from G. hirsuta .

Etymology

From Latin rostrata , provided with a hook, with reference to the shape of the apophysis of the phallobase.