Pachyserica zhanbaoxiangi 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 : 50-51

Pachyserica zhanbaoxiangi Ahrens, Zhao, Pham & Liu , new species

Fig. 21F–K

Type material examined. Holotype ♂ “ CHINA: Guangdong, Shaoguan , Nanling N. R., nr. Shikengkong, N 24°55′40″, E 112°59′2″, 1660 m, 30.V–4.VI.2022 (at light), lgt. X.-H. Ye, B.-X. Zhan & Y.-S. Ma ” ( SCAU).

Description of holotype. Length: 9.2 mm, length of elytra: 6.6 mm, width: 4.6 mm. Body oblong and convex, including legs entirely reddish brown, antennae yellowish brown, pronotum and ventral surface darker, frons and elytral intervals dark green, dorsal surface dull, head and pronotum with yellow, long, erect setae, with adpressed, lanceolate or oblong, white setae, elytra additionally with a few longer, lanceolate or fine semierect setae.

Labroclypeus subrectangular, distinctly wider than long, widest at base, lateral margins straight and subparallel, strongly convergent near broadly rounded anterior angles; anterior margin very weakly emarginated and strongly reflexed; lateral margins weakly reflexed; surface flat, dull, finely and irregularly punctate, with dense, long and erect setae; frontoclypeal suture distinct, finely incised and weakly elevated, weakly curved; smooth area anterior to eye slightly wider than long, moderately shiny; ocular canthus moderately long and narrow (slightly longer than 1/3 of ocular diameter), with three moderately long setae in apical half. Frons flat, on anterior half with moderately dense punctures and few minute, adpressed and lanceolate setae, behind eyes lanceolate seta also present but much denser, with sparse, long and erect setae behind frontoclypeal suture and besides eyes. Eyes large, ratio diameter/interocular width: 0.7. Antenna with ten antennomeres; antennomeres three and four almost as wide as long, antennomeres five to seven transverse and short, club with three antennomeres, 1.2 times as long as remaining antennomeres combined and straight. Mentum weakly elevated, flattened anteriorly. Labrum moderately produced, shallowly but broadly emarginate medially.

Pronotum trapezoidal, distinctly wider than long, widest at base, lateral margins slightly concave in basal half and strongly convergent anteriorly, in anterior half slightly convex and strongly convergent anteriorly; anterior angles not produced, broadly rounded in tip; posterior angles almost right-angled, somewhat rounded at tip; anterior margin straight, with distinct and complete anterior marginal line; surface densely and finely punctate, a shallow median groove on its posterior half and a transverse portion at each side impunctate, each puncture bearing a short, adpressed, lanceolate seta, setae laterally denser and thicker; anterior and lateral margins with dense, long, erect setae; hypomeron distinctly carinate, carina strongly produced ventrally. Scutellum long, triangular, finely and densely punctate, with adpressed, scale-like setae, basomedial and apical areas impunctate and glabrous.

Elytra oval, widest at posterior third, striae distinctly impressed, finely and densely punctate, intervals weakly convex, dark green almost from base to apex, generally smooth and glabrous, not interrupted by aggregations of fine punctures, punctures on intervals bearing each an adpressed, lanceolate seta, additionally with few longer, semi-erect setae and some fine, erect ones; 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 densely punctate, metasternum laterally and metepisternum with dense, adpressed, scale-like setae and fine, erect setae, metasternal disc and anteriorly additionally with fine, erect setae, hypomeron basally and metacoxa laterally with same scale-like setae but smaller in size; metacoxa laterally additionally with a few robust setae; abdominal sternites finely and moderately densely punctate, with a transverse row of large punctures, each bearing a short seta, with dense, adpressed, scale-like setae laterally. Mesosternum between mesocoxae almost as wide as mesofemur. Ratio of length of metepisternum/metacoxa: 1/1.45. Pygidium moderately convex, dull, with a wide, impunctate midline, otherwise finely and densely punctate, with dense, adpressed scale-like setae in basal half and with dense, erect long setae in apical half.

Legs slender; femora with two longitudinal rows of setae, finely and densely punctate; metafemur moderately shiny, anterior margin acute, without a continuously serrated line behind anterior margin; ventral posterior margin serrated in apical half and weakly 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: 1/3.9; dorsal margin sharply carinate, with two groups of spines, basal group before middle, apical group at three quarters of metatibial length, basally with a few single, robust setae; lateral face longitudinally concave, finely and densely punctate, with longitudinal wrinkles; ventral margin serrated, with three robust setae, apical two ones more distant; medial face longitudinally grooved and glabrous; apex interiorly near tarsal articulation concavely truncate, finely serrated. Tarsomeres dorsally smooth, ventrally with sparse, minute setae; meso- and metatarsomeres with a fine serrated ridge ventrally; metatarsomeres laterally carinate, glabrous ventrally; first metatarsomere as long as following two tarsomeres combined and distinctly longer than dorsal tibial spur. Protibia short, bidentate, external margin smooth; anterior claws symmetrical, basal tooth wider than the apical one.

Aedeagus: Fig. 21H–K . Habitus: Fig. 21F, G . Female unknown.

Diagnosis. Pachyserica zhanbaoxiangi new species differs from the most similar P. janbezdeki Ahrens, 2006 by the distinctly narrower basal lobe of right paramere.

Etymology. This species (noun in genitive case singular) is named after one of the collectors, Mr. Bao-Xiang Zhan (Guiyang, China).

New records (in alphabetical order)

Figures

FIGURE 21. A–E: Pachyserica sanqingshanensis new species (holotype); F–K: P. zhanbaoxiangi new species (holotype); A, H: aedeagus, left side lateral view; C, K: aedeagus, right side lateral view; B, J: parameres, dorsal view; I: aedeagus, dorsal view; D, F: habitus, dorsal view; E, G: habitus, lateral view. Scale bar: 0.5 mm. Habitus images not to scale.