Gastroserica stictica, Ahrens, Dirk & Pacholátko, Petr, 2003

Ahrens, Dirk & Pacholátko, Petr, 2003, New data on the distribution of species of Gastroserica Brenske, 1897, with descriptions of five new taxa from China and Laos (Coleoptera: Scarabaeidae: Sericini), Zootaxa 342, pp. 1-18 : 11-13

Gastroserica stictica sp. n. ( Figs 13–15 )

Type material: Holotypus: ɗ “Laos­ NE, Hua Phan prov., Ban Saluei, Phu Phan Mt., 20°15'N, 104°02'E, 1500­2000 m, D. Hauck leg. 26.iv.­11.v.2001 ” ( TICB).

Description. Length: 7.1 mm, length of elytra: 4.6 mm, width: 3.7 mm. Body oval, ventral surface, labroclypeus, legs, intervals three to five of elytra, lateral margins, and median stripe of pronotum yellowish­brown, antennal club, frons, elytral margins, lateral and sutural intervals, spots on intervals, and pronotal disc dark brown, dark portions with metallic­green shine, abdominal sternites and pygidium black, dorsal surface dull, with moderately dense erect setae mixed with dense and short setae.

Labroclypeus subrectangular and moderately broad, widest at middle, lateral margins almost straight and subparallel, anterior angles moderately rounded, lateral border and ocular canthus produced into a distinct obtuse angle, anterior margin moderately reflexed and not sinuate medially but weakly convex; surface feebly convex medially and moderately shiny, coarsely but moderately densely punctate, with a few fine punctures only and numerous long, erect setae; frontoclypeal suture distinctly impressed and weakly curved; smooth area in front of eye as wide as long; ocular canthus moderately long and slender, finely and sparsely punctate, with two terminal setae. Frons moderately shiny, with coarse and fine moderately dense punctures and erect setae, posteriorly dull. Eyes moderately large, ratio of diameter/ interocular width: 0.6. Antenna yellow, 10­segmented; club dark with four antennomeres equal in length, 1.5 times as long as the remaining antennomeres combined. Mentum elevated and flattened anteriorly.

Pronotum moderately long, widest at base, lateral margins in posterior half moderately convergent anteriorly, before posterior angles shallowly sinuate, in anterior third strongly convex and convergent, anterior angles not produced but strongly rounded, almost obsolete, posterior angles almost right­angled and weakly produced outward, anterior margin weakly convex medially, with a distinct and fine marginal line, basal margin without marginal line; surface with moderately dense and fine punctures, glabrous, with minute setae in punctures only; anterior and lateral borders setaceous; basal margin of hypomeron strongly produced ventrally, before base distinctly transversely sulcate. Scutellum long, apex weakly rounded, with fine and dense punctures, medially smooth, minute setae present in the punctures.

Elytra oblong, widest at middle, except intervals 3­5 dark brown, striae distinctly impressed and finely densely punctate, intervals weakly convex, sutural interval strongly convex and more elevated, with fine and sparse punctures which are almost concentrated along the striae, minutely setose in the punctures, odd intervals with single coarse punctures bearing strong erect setae, interior apical angle of elytra with a strong seta; intervals three and five with four dark and circular spots, interval four with a long spot at middle; epipleural edge moderately strong, ending at the strongly convex external apical angle of elytra, epipleura densely setaceous, apical border membraneous, without short microtrichomes.

Ventral surface dull, with large and dense punctures, with dense, short, adpressed setae; metacoxa partly glabrous, laterally with fine adpressed setae; each abdominal sternite with indistinct transversal row of coarse punctures bearing short strong setae between fine and dense punctation, all sternites with fine, short setae. Mesosternum between mesocoxae almost as wide as mesofemur with irregularly scattered, strong setae. Ratio of length of metepisternum/ metacoxa: 1/ 1.7. Pygidium long, apically produced and strongly convex, with fine and dense punctures bearing fine setae and a few robust punctures bearing robust setae, without smooth midline.

Legs moderately slender and shiny; femora finely densely punctate and setose, with two longitudinal rows of setae; anterior edge of metafemur acute, lacking an adjacent serrated line, posterior margin weakly convex, with a few fine setae medially, ventrally weakly widened in apical half and shortly serrate distally, dorsally serrate, with short setae. Metatibia moderately broad and short, at middle convexly widened, ratio width/ length: 1/ 3.5, dorsally sharply edged, with two groups of spines, the basal group at one third, apical one at two third of metatibial length, basally with a few single spines in punctures; lateral face longitudinally convex, with moderately dense and fine punctures, some of them longitudinally impressed, sparsely and finely setose; ventral edge serrated, with three strong and long spines, of which the distal one is more distant; medial face not punctate and smooth, apex interiorly near tarsal articulation sharply truncate. Tarsomeres dorsally glaborus and finely punctate, ventrally with sparse, short setae; metatarsomeres dorsally with strong longitudinal impressions, ventrally with a strongly serrated ridge, laterally with a strong longitudinal carina, first metatarsomere as long as the following two tarsomeres combined and more than twice as long as the upper tibial spur. Protibia short, bidentate, protarsal claws symmetrical.

Aedeagus: Figs 13–15 .

Diagnosis. G. stictica sp. n. has an external morphology which is very similar to that of G. namthana Ahrens and G. contaminata sp. n. It may be differentiated from both taxa by its longer antennal club in male as well as by the morphology of aedeagus: the phallobase has apically at the left side a long and broad apophysis, wich is apically in cross section s­shaped, the parameres are slender, very long (little longer than the phallobase) and medially moderately curved.

Derivatio nominis. From the latin word sticticus meaning punctate.

Figures

FIGURES 13 – 15: Gastroserica stictica sp. n. (Holotype: Laos, Hua Phan prov., Ban Saluei, Phu Phan Mt.); 13, 15 ­ Aedeagus lateral view, 14 ­ Parameres dorsal view. Scale: 0.5 mm.