Serica (Serica) hongyii 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 : 17-18

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

Fig. 5H–M

Type material examined. Holotype ♂ “ CHINA: TIBET, Nyingchi, Motuo , 90k, 1700 m, 29.628135° N, 95.483992° E, 15.VII.2023, Zheng Xu-Hong-Yi, Chen Zhi-Teng, Gong De-Wen leg.” ( SCAU) . Paratypes: 1 ♂, 1 ♀ “ CHINA: TIBET, Nyingchi, Motuo , 90k, 1700 m, 29.628135° N, 95.483992° E, 15.VII.2023, Zheng Xu-Hong-Yi, Chen Zhi-Teng, Gong De-Wen leg.” ( CZMZ) .

Description of holotype. Length: 7.8 mm, length of elytra: 5.4 mm, width: 3.7 mm. Body oblong, dark yellowish brown, antennae and legs yellow, elytra with dense, small, dark spots; except shiny head dorsal surface dull, sparsely setose, usually with lanceolate, white, adpressed setae and fine, long, erect, yellow setae.

Labroclypeus subrectangular, 1.2 times wider than long, widest at middle, lateral margins weakly convex and convergent anteriorly and posteriorly, more strongly convergent before produced anterior angles which are blunt at tip, anterior margin deeply emarginate medially; margins strongly reflexed near anterior angles, otherwise weakly reflexed; surface uneven, shiny, finely and densely punctate, smooth and glabrous on basomedial portion, with a few long, erect setae behind anterior margin; frontoclypeal suture finely incised, flat, weakly curved; smooth area anterior to eye large and convex, approximately 1.5 times as wide as long; ocular canthus short and narrow (1/4 of ocular diameter), smooth, with one short terminal seta. Frons shiny, basal half with dull toment, with an elevated midline behind frontoclypeal suture, with fine but irregularly scattered punctures, with a few erect setae beside eyes and before dull portion. Eyes very large, ratio diameter/ interocular width: 1.0. Antenna yellowish with ten antennomeres; antennomeres three to seven transverse and short; club with three antennomeres, 1.6 times as long as remaining antennomeres combined and convex. Mentum strongly elevated, anteriorly flattened, with very dense, robust setae. Labrum transverse and short, confined to the labroclypeal emargination, deeply emarginated medially.

Pronotum narrow, heart-shaped, widest at middle, concavely narrowed basally, in anterior half lateral margins weakly convex and strongly convergent anteriorly, anterior angles not produced and broadly rounded, posterior angles acute; anterior margin with a fine and complete marginal line; surface densely and finely punctate, midline impunctate at basal half, otherwise on disc irregularly impunctate, with several sparse, white spots formed by an aggregation of a few oblong scales, other punctures each bearing a minute seta; anterior and lateral margins sparsely setose with long, fine, and recumbent setae; hypomeron carinate. Scutellum triangular, dull, coarsely and densely punctate, glabrous, at base impunctate, glabrous.

Elytra oblong, widest at middle, striae indistinctly impressed, finely and densely punctate, intervals weakly convex, with fine, moderately dense punctures, intervals with sparsely scattered adpressed, lanceolate setae and a few fine, long, semierect setae, with dark spots completely impunctate; epipleural edge fine, ending at moderately curved external apical angle of elytra, with a small dent at apical border; epipleura sparsely setose, apical border narrowly membranous, with a very fine membranous rim of fine microtrichomes (magnification 100x).

Ventral surface dull, with large and dense punctures, hypomeron with a few long setae, mesosternum and anterior border of metepisternum densely setose, metasternum on disc sparsely punctate and with a few long setae, metacoxa laterally with a few robust setae, otherwise glabrous; abdominal sternites finely and moderately densely punctate, with a transverse row of coarse punctures, each bearing a long seta. Mesosternum between mesocoxae half as wide as mesofemur. Ratio of length of metepisternum/metacoxa: 1/1.5. Pygidium weakly convex and dull, finely and densely punctate, with smooth darker midline, with short and adpressed, fine setae, lateral and apical margins with moderately dense, long, erect setae.

Legs very slender and long; all femora shiny, with two longitudinal rows of fine, short setae, smooth and glabrous between the rows; metafemur with acute anterior margin, without a continuously serrated line behind anterior margine, posterior margin serrated ventrally in apical half and not widened, completely serrated dorsally, 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: 1/5.0; dorsal margin not 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; external face slightly longitudinally concave, nearly impunctate, with numerous longitudinal wrinkles; ventral margin serrated, with four robust equidistant setae; medial face longitudinally concave, with sparse, fine punctures, apex interiorly near tarsal articulation distinctly but bluntly truncate, finely serrated. Tarsomeres ventrally with sparse, short setae, dorsally smooth; protarsomeres thickened, with robust setae ventrally, metatarsomeres laterally carinate, with a strongly serrated ridge ventrally; first metatarsomere equally as long as following two tarsomeres combined and twice as long as dorsal tibial spur. Protibia long, bidentate, external margin with a few small teeth in basal two thirds, anterior claws asymmetrical, basal tooth of inner claw enlarged and lobiform, with a small tooth at its external face, the long and strongly curved apical tooth in base strongly bent externally.

Aedeagus: Fig. 5J–M . Habitus: Fig. 5H, I .

Diagnosis. Serica hongyii new species is similar to S. zianii Sreedevi, Speer, Fabrizi & Ahrens, 2018 and S. xizang new species judging from the male genitalia. It can be distinguished by the narrow base of pronotum (distinctly narrower than base of elytra in the new species but equally wide in the other two species), protarsomeres thickened in male (not thickened in the other two species) and distinctly shorter right paramere.

Etymology. This species (noun in genitive case singular) is named after one of its collectors, Mr. Xu-Hong-Yi Zheng (Nanjing Normal University, China).

Variation. Length: 7.9–8.2 mm, length of elytra: 5.3 mm, width: 3.6–4.1 mm. Female: Body oval; eyes small, ratio diameter/interocular width: 0.66, antennal club little shorter than remaining antennomeres combined; legs shorter, protarsomeres not thickened, anterior claws symmetrical, basal tooth of inner claw normal.

Figures

FIGURE 5. A–G: Serica cuona new species (holotype); H–M: S. hongyii new species (holotype); A, J: aedeagus, left side lateral view; D, M: aedeagus, right side lateral view; C, K: parameres, dorsal view; B, L: aedeagus, dorsal view; E, H: habitus, dorsal view; G, I: habitus, lateral view; F: head, dorsal view. Scale bar: 0.5 mm. Habitus images not to scale.