Serica (s. l.) nhiae 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 : 32-33

Serica (s. l.) nhiae Ahrens, Zhao, Pham & Liu , new species

Fig. 13A–F

Type material examined. Holotype ♂ “N VIETNAM — Lao Cai province, Hoang Lien Natl Park surr. Sa Pa pass, at light (~ 1900m) 27.V.2011 / L. Bartolozzi, S. Bambi, F. Fabiano, E. Orbach leg. (Num. Maggazzino 2909)” ( MZUF / VNMN).

Description of holotype. Length: 10.6 mm, length of elytra: 8.4 mm, width: 6.3 mm. Body elongate eggshaped, dark reddish brown, partly with greenish toment, elytra with dark spots, even intervals almost completely dark, antenna yellowish, legs brown; dorsal surface dull and densely covered with short yellow setae being bent posteriorly.

Labroclypeus subtrapezoidal, distinctly wider than long, widest at base, lateral margins convex and strongly convergent anteriorly, anterior angles acute; anterior margin deeply and widely emarginate medially; margins weakly reflexed; surface flat and shiny, finely and densely punctate, shortly, finely and densely setose, behind anterior margin glabrous; frontoclypeal suture finely incised, weakly convex; smooth area anterior to eye large and flat, as wide as long; ocular canthus moderately long and slender (1/3 of ocular diameter), with a few fine punctures bearing each a short seta. Frons completely dull and flat, with fine and very dense punctures, evenly covered with short yellow setae being bent backwards and longer erect setae. Eyes small, ratio diameter/ interocular width: 0.49. Antenna with ten antennomeres; antennomeres three to five as wide as long, antennomeres six and seven transverse and short; club with three antennomeres, as long as remaining antennomeres combined and straight. Mentum weakly elevated, anteriorly flattened. Labrum transverse, elyptical, produced along middle, moderately emarginate medially.

Pronotum subtrapezoidal, widest shortly before base, lateral margins evenly convex and strongly convergent anteriorly; anterior angles distinctly produced and acute; posterior angles strongly rounded; anterior margin medially with a fine marginal line and very weakly produced medially; surface densely and coarsely punctate, with dense short yellow setae bent posteriorly; lateral margins sparsely setose; hypomeron carinate at base, weakly produced ventrally. Scutellum large, triangular, finely and very densely punctate, basal midline smooth, pilosity as in lateral pronotum.

Elytra oval, widest at middle, striae indistinctly impressed, finely and densely punctate; intervals flat, with fine, very dense punctures; dark spots impunctate or with less dense punctures, with fine, short pilosity as in pronotum, without longer, erect setae; epipleural edge fine, ending at moderately curved external apical angle of elytra, epipleura densely setose, apical margin without a very fine membranous rim composed of minute microtrichomes (magnification 100x).

Ventral surface dull, finely and densely punctate, including metacoxa and abdominal sternites densely shortly setose; abdominal sternites with a transverse row of coarse punctures, each bearing a long seta, otherwise shortly setose as rest of ventral surface; ultimate sternite at middle 1.5 times as long as penultimate one. Mesosternum between mesocoxae half as wide as the slender mesofemur. Ratio of length of metepisternum/ metacoxa: 1/ 1.39. Pygidium strongly convex and dull, finely and densely punctate, smooth midline narrow, with dense short setae.

Legs slender; femora with two longitudinal rows of setae, coarsely and densely punctate between the rows, with robust setae on basal half; metafemur shiny, anterior margin acute, without a continuously serrated line behind anterior edge, posterior margin ventrally 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/ 4.8, dorsally 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; external face impunctate, with dense superficial longitudinal wrinkles; ventral margin serrated, with two very widely separated robust setae; medial face glabrous and smooth; apex interiorly near tarsal articulation concavely truncate. Tarsomeres ventrally with sparse, minute setae, dorsally smooth. Metatarsomeres ventrally glabrous, laterally and dorsally carinate, with a strongly serrated ridge ventrally; first metatarsomere little shorter than following two tarsomeres combined and almost twice as long as dorsal tibial spur; mesotarsomeres not carinate. Protibia moderately long, bidentate, external margin serrate, with a few small teeth at base; anterior claws asymmetrical, basal tooth of inner claw concavely excavate at apex.

Aedeagus: Fig. 13A–D . Habitus: Fig. 13E, F . Female unknown.

Diagnosis. Serica nhiae new species differs from all other species of the S. velutina group by the shape of parameres: both are curved dorsally (lateral view), the right paramere has a large concave basal lobe; the left paramere is at apex evenly but sharply narrowed.

Etymology. The new species (adjective in genitive case singular) is named after Dr. Nhi Thi Pham in gratitude for her support for Phu Pham.

Figures

FIGURE 13. A–F: Serica nhiae new species (holotype); G–K: S. (T.) yexiaohani new species (holotype); A, I: aedeagus, left side lateral view; D, K: aedeagus, right side lateral view; B, J: parameres, dorsal view; C: aedeagus, dorsal view; E, G: habitus, dorsal view; F, H: habitus, lateral view. Scale bar: 0.5 mm. Habitus images not to scale.