Serica (Serica) gwangjuensis Ahrens, Zhao, Pham & Liu, 2024

Ahrens, Dirk, Zhao, Ming-Zhi, Pham, Phu Van & Liu, Wan-Gang, 2024, Taxonomic updates on Pachyserica Brenske, 1898 and Serica MacLeay, 1819 reveal 38 new species and new challenges of Sericini systematics regarding DNA barcodes and genus-level diagnostic key characters (Coleoptera: Scarabaeidae: Sericinae), Zootaxa 5491 (1), pp. 1-89 : 7-8

Serica (Serica) gwangjuensis Ahrens, Zhao, Pham & Liu , new species

Fig. 1A–E

Type material examined. Holotype ♂ “ 06.07.2010 Mudeungsan, Gwangju ( Südkorea) leg. T. Kölkebeck / Asia Sericini spec. 862” ( ZFMK) . Paratypes: 1 ♂, 3 ♀♀ “ 06.07.2010 Mudeungsan , Gwangju ( Südkorea) leg. T. Kölkebeck ” ( ZFMK) , 4 ♂♂, 1 ♀ “ 27.06. 2010 Beomeosa , Busan ( Südkorea) leg. T. Kölkebeck ” ( ZFMK) , 1 ♂ “ Republic of Korea Gyeongsangnam-do Jirisan N.P. N35°22.241′, E127°46.853′ 12.– 15.6.2018, 581m Walter Grosser lgt.” ( ZFMK) .

Description of holotype. Length: 7.5 mm, length of elytra: 5.5 mm, width: 4.1 mm. Body oblong, including antenna and legs yellowish brown, eyes and frons blackish, elytra without dark spots, dorsal surface shiny and finely shortly setose.

Labroclypeus little wider than long, widest at base, lateral margins convex and strongly convergent, anterior angles almost blunt, anterior margin deeply but narrowly emarginate medially, anterior and lateral margins weakly reflexed; surface flat and shiny, finely and densely punctate, distance between punctures smaller than their diameter, partly producing some very superficial transverse wrinkles; surface throughout with dense, long, erect setae; frontoclypeal suture indistinctly incised, slightly elevated and weakly curved; smooth area anterior to eye moderately large and weakly convex, approximately 1.2 times as wide as long; ocular canthus moderately long and slender (1/4 of ocular diameter), smooth, with one very short terminal seta. Frons flat and shiny; surface with fine and dense punctures and fine, dense, erect pilosity as in labroclypeus and the rest of the body surface. Eyes moderately large, ratio diameter/interocular width: 0.65. Antenna with nine antennomeres; antennomeres three and four slightly longer than wide, antennomeres five and six transverse and short; club with three antennomeres, 2.3 times as long as remaining antennomeres combined and reflexed. Mentum weakly elevated, anteriorly flattened. Labrum transverse, short, moderately produced, deeply emarginate medially.

Pronotum subtrapezoidal, wider than long, widest at base, lateral margins moderately evenly convex and strongly convergent anteriorly, anterior angles weakly produced, blunt, posterior angles blunt, weakly rounded at tip; anterior margin medially with a complete but fine marginal line and strongly convexly produced; surface densely and finely punctate, with fine, dense, posteriorly bent setae; anterior and lateral margins with moderately long and sparse setae; hypomeron carinate at base. Scutellum slender and long, triangular, apex well rounded, finely and evenly, densely punctate, with short setae as in pronotum.

Elytra oblong, widest at apical third, striae strongly impressed, finely and densely punctate, intervals convex, with fine, dense punctures concentrated along striae, uniformly yellow, with the sutural and epipleura slightly darker; punctures on intervals with fine, short setae which are bent posteriorly; epipleural edge fine, ending at moderately curved external apical angle of elytra, epipleura densely setose, apical border chitinous, without membranous rim of fine microtrichomes (magnification 100x).

Ventral surface moderately dull, partly weakly shiny, finely and densely punctate, moderately densely setose; metacoxa glabrous, with a few long setae only laterally; abdominal sternites finely and densely punctate, with a transverse row of coarse punctures, each bearing a short seta. Mesosternum between mesocoxae half as wide as the slender mesofemur. Ratio of length of metepisternum/metacoxa: 1/1.54. Pygidium weakly convex and weakly shiny, finely and densely punctate, smooth midline lacking, with partly dense, fine and short setae (similar to those in the rest of dorsal surface).

Legs slender; femora with two longitudinal rows of setae, between rows finely and not densely punctate; metafemur shiny, anterior margin acute, without a continuously serrated line behind anterior margin, ventral posterior margin serrated in apical half and not widened, dorsal posterior margin completely serrated, in basal half with a few long setae which are more than half as long as width of metafemur. Metatibia slender and long, widest at apex, ratio of width/length: 1/4.6; dorsal margin sharply carinate, with two groups of spines, basal group at first third, apical group at two thirds of metatibial length, basally with a few single, robust setae; lateral face longitudinally concave, superficially punctate, entirely covered with irregular wrinkles; ventral margin serrated, with two widely separated robust setae; medial face with a shallow longitudinal groove medially, sparsely punctate and glabrous; apex interiorly near tarsal articulation distinctly but bluntly truncate. Tarsomeres ventrally with sparse, very minute setae, meso- and metatarsomeres missing in the holotype; protibia moderately long, bidentate, external margin with a few small teeth in base half; anterior claws asymmetrical, basal tooth of inner claw small and lobiform.

Aedeagus: Fig. 1A–C . Habitus: Fig. 1D–E .

Diagnosis. Serica gwangjuensis new species is in shape of genitalia similar to S. hirsuta Kim & Kim, 2003 . Serica gwangjuensis new species differs from the latter by the narrower right paramere which is sharply pointed at apex and the almost reduced, small, sickle-shaped left paramere, which is barely visibly under the phallobasal membranes.

Etymology. The name of this new species (adjective in singular nominative case) is derived from its type locality, Gwangju.

Variation. Length: 7.4–7.6 mm, length of elytra: 5.4–5.6 mm, width: 4.0– 4.1 mm. Meso- and metatarsomeres dorsally with longitudinal wrinkles; metatarsomeres laterally and dorsally carinate, with a strongly serrated ridge ventrally, ventrally glabrous; first metatarsomere little shorter than following two tarsomeres combined and almost twice as long as dorsal tibial spur. Female: Antennal club distinctly shorter than remaining antennomeres combined, eyes smaller than in male: ratio diameter/interocular width: 0.46.

Figures

FIGURE 1. A–E: Serica gwangjuensis new species (holotype); F–J: S. assingi new species (holotype); A, H: aedeagus, left side lateral view; C, J: aedeagus, right side lateral view; B, I: parameres, dorsal view; D, F: habitus, dorsal view; E, G: habitus, lateral view. Scale bar: 0.5 mm. Habitus images not to scale.