Serica (Serica) jiangda 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 : 19-20

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

Fig. 6G–K

Type material examined. Holotype ♂ [ China] “ Jiangda , Xizang, 26.VII.1976, 3400m, leg. Han Yinheng / Asia Sericini 1332 spec.” ( IZAS) . Paratypes: 1 ♂, 1 ♀ [ China] “ Jiangda , Xizang, 26.VII.1976, 3400m, leg. Han Yinheng ” ( IZAS, ZFMK) , 1 ♂ [ China] “ Mangkang , Xizang, 12.VI.2004, leg. Ba Yibin, Shi Aimin” ( HBUM) .

Description of holotype. Length: 8.8 mm, length of elytra: 7.0 mm, width: 4.1 mm. Body oblong, including legs reddish brown, frons darker, antenna yellow, elytra with more or less large dark spots, punctures on elytra lighter, dorsal surface dull; elytra with sparse, short, adpressed white setae, otherwise glabrous.

Labroclypeus as wide as long, widest at base, lateral margin almost straight and moderately convergent anteriorly, anterior angles acute, anterior margin widely and deeply emarginate medially, margins strongly reflexed; surface flat, shiny, finely and densely punctate, with dense transverse wrinkles and a few long, erect setae behind anterior margin; frontoclypeal suture distinct, finely incised and weakly curved; smooth area anterior to eye large and convex, about 1.5 times as wide as long; ocular canthus moderately long and narrow triangular (1/4 of ocular diameter), smooth, with short terminal seta. Frons flat, entirely dull; surface with fine and irregularly dense punctures, with a few short setae on disc and beside eyes. Eyes large, ratio diameter/interocular width: 0.86. Antenna with nine antennomeres; antennomeres six and seven transverse and short; club with three antennomeres, three times as long as remaining antennomeres combined and strongly reflexed. Mentum anteriorly weakly elevated. Labrum transverse, short, moderately produced, moderately emarginate medially.

Pronotum moderately wide, widest at base, lateral margins in basal half almost straight and weakly convergent anteriorly, in anterior half convex and strongly convergent anteriorly, anterior angles weakly produced and rounded, posterior angles blunt, rounded at tip; anterior margin medially convex and with a complete, distinct marginal line; surface densely and finely punctate, with minute setae in punctures, otherwise glabrous; anterior and lateral margins with moderately long and sparse setae; hypomeron not carinate. Scutellum slender and long, dull, triangular, finely and densely punctate, on basal midline punctures widely absent.

Elytra oblong, widest at apical third, striae weakly impressed, finely and densely punctate, intervals flat, with fine, moderately dense punctures, dark spots completely smooth; all intervals with sparse, short, adpressed, white, partly scale-like setae; 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 dull, finely and not 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: 1/1.31. Pygidium moderately convex and dull, finely and densely punctate, smooth midline lacking, with a few moderately dense and short setae.

Legs slender; femora with two longitudinal rows of setae, coarsely and not densely punctate between the rows, with robust setae on basal half; 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 half as long as width of metafemur. Metatibia slender and long, widest at apex, ratio of width/length: 1/5.8; dorsal margin sharply carinate, with two groups of spines, basal group shortly before middle, apical group at three quarters of metatibial length, basally with a few single, robust setae; lateral face longitudinally concave, impunctate but robustly wrinkled; ventral margin serrated, with five irregularly distributed 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, minute setae, dorsally impunctate and without wrinkles; metatarsomeres laterally and dorsally carinate, with a strongly serrated ridge ventrally, ventrally glabrous; first metatarsomere distinctly shorter than following two tarsomeres combined and less than twice as long as dorsal tibial spur. 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, basal tooth of external claw normal.

Aedeagus: Fig. 6I–K . Habitus: Fig. 6G–H .

Diagnosis. Serica jiangda new species differs from S. schoenmanni Ahrens, 2005 by the apically more strongly bent right paramere (lateral view), and the left paramere, which is longer, medially wider, and straight.

Etymology. The name of this new species (noun in apposition) is derived from its type locality, Jiangda (Xizang, China).

Variation. Length: 7.7–8.9 mm, length of elytra: 6.4–7.1 mm, width: 3.9–4.2 mm. Female: Slightly larger in body size; antennal club short, as long as remaining antennomeres combined; claws of protarsomeres symmetric; eyes smaller, ratio diameter/interocular width: 0.57.

Figures

FIGURE 6. A–F: Serica xizang new species (holotype); G–L: S. jiangda new species (holotype); A, I: aedeagus, left side lateral view; D, L: aedeagus, right side lateral view; C, K: parameres, dorsal view; B, J: aedeagus, dorsal view; E, G: habitus, dorsal view; F, H: habitus, lateral view. Scale bar: 0.5 mm. Habitus images not to scale.