Serica (s. l.) longidentata Zhao & Ahrens, 2023

Zhao, Ming-Zhi & Ahrens, Dirk, 2023, New species of the tribe Sericini Kirby, 1837 from China, with further updates on their taxonomy and distribution (Coleoptera: Scarabaeidae: Sericinae), Zootaxa 5361 (2), pp. 181-220 : 200-203

Serica (s. l.) longidentata Zhao & Ahrens , new species

( Figs 8A , 9A )

Type material examined. Holotype. ♂ ( SCAU), “ 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. Ye XH, Zhan BX & Ma YS” . Paratypes. 10♂♂, 1♀ ( CZMZ, SCAU), “ 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. Ye XH, Zhan BX & Ma YS” ; 1♂ ( SCAU), “ 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. Ye XH, Zhan BX & Ma YS // Se-MS-2” ; 2♂♂ ( CZMZ), “ CHINA: GUANGDONG, Nanling Nature Reserve , 960 – 1189 m, 22–26.V.2021, Yun-Shu Ma leg.” ; 1♂ ( SCAU), “ CHINA: Hunan, Chenzhou , Guidong , Bamianshan Village , 2021. V.11–15, 25°58′44″N / 113°42′46″E ~ 1000 m, Ming-Zhi Zhao & Xin-Yang Jia, light trap ” .

Description of the holotype. General. Body elongated ovoid, moderately convex; body color dark brown, including mesofemur and metacoxa with greenish toment, pronotum and elytra with some darker patterns and strong coppery luster; labroclypeus dark green, legs reddish brown, palpi and antennae yellowish brown, shiny. Setae yellow, scale-like setae on pronotum and elytra pale.

Head. Labroclypeus subtrapezoidal, distinctly wider than long, widest at base, ratio of maximum length/ width: 1/ 1.78; lateral margins almost straight and weakly convergent anteriad, anterior angles broadly rounded at apex, anterior margin widely and distinctly emarginate; margins moderately reflexed; surface flat, with dense and coarse punctures, some punctures on anterior half each bearing a moderately long and erect seta; frontoclypeal suture finely incised, almost straight medially; smooth area anterior to eye large and flat, approximately 1.5 times as wide as long; ocular canthus moderately long and slender (1/3 of ocular diameter), with a minute terminal seta. Frons flat, with moderately dense and small punctures each bearing a moderately long and backwards-directed seta, mixed with some short semi-erect setae, inner margin of eye with some moderately long, erect setae. Eyes moderately large, ratio diameter/ interocular width: 0.61. Antenna with nine antennomeres; antennomeres 5 slightly wider than long, antennomere 6 transverse and short; club with three antennomeres, 1.6 times as long as remaining antennomeres combined and straight. Mentum strongly and transversely elevated anteriorly. Labrum strongly produced, widely and deeply concave medially.

Pronotum subtrapezoidal, widest before base; lateral margins evenly reflexed and strongly convergent anteriad; anterior angle moderately produced and acute at apex, posterior angle obsolete; hypomeron not carinate at base; anterior margin with a fine marginal line; surface with moderately dense and coarse punctures, sparsely bearing lanceolate setae, which are more oblong on disc, a longitudinal and impunctate area and an reflexed and less punctate area at each side glabrous, anterior and lateral margins with sparse and long erect setae.

Scutellum large, triangular, apex somewhat rounded; basomedially impunctate, other portions densely and coarsely punctate, sparsely bearing some lanceolate setae.

Elytra elongated, widest at apical quarter. Striae distinctly impressed, strial punctures dense and fine; intervals weakly convex, with dense and small punctures, dark spots impunctate, scarcely bearing some large and lanceolate setae, base between humeral convexity and scutellum with an aggregation of small and lanceolate setae, being oblong near prominent humeral convexity. Epipleura ending at moderately curved external apical angle of elytron, with a row of moderately dense and long to moderately long erect setae, apex with a moderately long erect seta, apical margin with a very fine membranous rim composed of microtrichomes.

Ventral thoracic surface. Ventral thoracic surface and metacoxae with moderately dense and small punctures, most of the punctures each bearing a short and semi-erect seta, disc of meso- and metasternum with denser punctures and longer setae, metasternum posteromedially with a sparsely punctate and glabrous area, metacoxae scarcely setose. Mesosternum between mesocoxae slightly narrower than mesofemur. Ratio of length of metepisternum/ metacoxa: 1/ 1.34.

Abdomen. Abdominal ventrites with moderately dense and fine punctures each bearing a minute seta, each ventrite with a transverse row of spiniform and short recumbent setae, medially with some semi-erect and moderately long setae, ultimate ventrite medially with a tuft of moderately long setae and laterally with scattered short setae. Ultimate ventrite medially nearly twice as long as penultimate one. Abdominal ventrites strongly curved in lateral view. Pygidium strongly convex, with impunctate midline, posterior margin moderately reflexed; surface with scattered and small punctures, disc with sparse and lanceolate seta, some moderately to long setae presented laterally and somewhat aggregated preapically.

Femora. Profemur dull at dorsal third, with a row of moderately long setae near dorsal margin. Mesofemur dull, two longitudinal rows of moderately dense punctures each bearing a short to moderately long seta. Metafemur shiny, two longitudinal rows of moderately dense punctures each bearing a short seta; anterior margin moderately sharp, ventral posterior margin finely serrate at apical third, dorsal posterior margin completely serrate, a row of moderately long setae situated between the latter two margins.

Tibiae. Protibia moderately long, bidentate, tibial teeth protruding and acute, lateral margin with several small teeth at basal half. Metatibia slender, widest before apex, ratio of width/length: 1/4.38; dorsal margin sharply carinate except for basal sixth; lateral face longitudinally wrinkled, dorsally with three groups of robust setae touching the dorsal carina, basal group at one sixth, mesial one at one third, distal group at three quarters of metatibial length, basally with several smaller setae; ventral margin serrate except for base, with three spiniform setae of which distal two are widely distant, base with several short setae; medial face impunctate; apex interiorly serrate, near tarsal articulation nearly truncate.

Tarsi. Protarsomeres short, pro- and mesotarsomeres with moderately dense and minute setae ventrally. Meso- and metatarsomeres serrate ventrally. Metatarsomeres carinate dorsally and laterally, with another weaker carina between dorsal and lateral carinae, first metatarsomere slightly shorter than following two tarsomeres combined and twice as long as dorsal tibial spur. Protarsal claws asymmetric, basal tooth of the inner claw distinctly wider, anterior apical angle short lobiform, posterior apical angle sharply pointed, with a blunt, additional basal tooth, the basal tooth of the outer claw normally developed.

Male genitalia. Fig. 9A .

Variation. Male. Highly similar to holotype in all external and genital features. Female. Combined length of antennomeres 1 to 6 slightly longer than in male, and longer than antennal club of itself; eyes smaller than in male, ratio diameter/ interocular width: 0.57; protarsal claws symmetrical, similar to outer protarsal claw of male but ventral lobe slightly wider.

Measurements. Length: 10.2–11.9 mm in males (holotype 11.9 mm), 11.3 mm in female; length of elytra: 7.9–8.9 mm in males (holotype 8.9 mm), 8.7 mm in female; width: 5.4–6.2 mm in males (holotype 6.0 mm), 6.4 mm in female.

Diagnosis. Serica longidentata Zhao & Ahrens , new species is very similar to S. dissimillima Ahrens, Fabrizi & Liu, 2022 in external appearance and shape of aedeagus. In the new species, the antennal club is longer (ratio length of club/ remainder antennomeres combined: 1.2 in S. dissimilima ). The inner lobe of right paramere has an elongated carina apically, which bears an acute tooth at base, while there is a small and acute tooth at apex in S. dissimilima . Additionally, inner margin of right paramere slightly protrudes before middle in the new species, whereas it is straight in S. dissimilima .

Etymology. The species name is derived from a combination of the Latin prefix “ longi- ” and the adjective “ dentatus ”, referring to the carinated preapical tooth of right paramere (adjective in nominative case singular).

Figures

FIGURE 8. Habitus indorsal view.A, Serica (s. l.) longidentata Zhao &Ahrens,new species,holotype; B, S. (s. l.) callosericoides Zhao & Ahrens, new species, holotype; C, S. (Taiwanoserica) liboyani Zhao & Ahrens, new species, holotype; D, S. (T.) yangzaichuni Zhao & Ahrens, new species, holotype. Scale bar = 5 mm.

FIGURE 9. Aedeagus. A, Serica (s. l.) longidentata Zhao & Ahrens, new species, holotype; B, S. (s. l.) callosericoides Zhao & Ahrens, new species, holotype; C, S. (Taiwanoserica) liboyani Zhao & Ahrens, new species, holotype; D, S. (T.) yangzaichuni Zhao & Ahrens, new species, holotype. a, aedeagus in left lateral view; b, parameres in dorsal view; c, aedeagus in right lateral view. Scale bar = 1 mm.