Pachyserica albopunctata 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 : 184-187

Pachyserica albopunctata Zhao & Ahrens , new species

( Figs 1C–D , 2E )

Type material examined. Holotype. ♂ ( SCAU), “ Guangdong, Nanling Nature Reserve , 2016-VI-29–31 ”.

Paratypes. 3♂♂, 1♀ ( SCAU), “ Guangdong, Nanling Nature Reserve , 2016-VI-29–31 ” ; 1♂, 1♀ ( SCAU), “ Guangdong, Nanling Nature Reserve, 2017-V-31 ” ; 2♂♂ ( SCAU, CZMZ), “ Nanling Nature Reserve , 2021.05.22 – 25” ; 1♂ ( CZMZ), “ CHINA, Guangdong, Shaoguan City , Shixing County, Chebaling Nature Reserve 2008-7-22 ~28” ; 1♂, 1♀ ( CZMZ), “ CHINA: Guangdong, Lianzhou , Sanshui Yao Co. nr. Xinba Vill. 25°7′N, 112°21′E, cca. 580 m, 5-7.VI.2023 light trap Ming-Zhi Zhao leg.” ; 1♂ ( CAU), “[China] Cujiang, Longsheng, Guangxi, 24.VI. 1982, 800 m, leg. Ji-Kun Yang ” .

Description of the holotype. General. Body shape ovoid, strongly convex, without metallic luster; antennae, palpi, and legs (except for all coxae, and part of pro- and mesofemora) shiny. Body generally reddish brown with grass greenish toment, apical half of elytra somewhat paler; shiny portions of legs iridescent; antennae yellow. Setae pale.

Head. Labroclypeus trapezoidal, ratio of maximum length/ width: 1/ 1.6; lateral margins curved and weakly convergent anteriad, anterior angle broadly rounded, anterior margin straight; margins weakly reflexed; disc bulging, with moderately dense and large punctures, several minute erect seta situated near margin, and some punctures on disc each bearing an oblong seta; frontoclypeal suture finely incised, curved medially; smooth area anterior to eye large and flat, twice as wide as long; ocular canthus moderately long (slightly shorter than 1/3 of ocular diameter), bearing two erect and short setae. Frons flat, with dense and large punctures, each puncture bearing an oblong seta, inner margin of eye with several short erect seta. Eyes very large, ratio diameter/ interocular width: 1.51. Antenna with ten antennomeres; antennomere 7 transverse and short; club straight, with three antennomeres, 0.8 times as long as remaining antennomeres combined. Mentum moderately and transversely elevated anteriorly. Labrum strongly produced, distinctly concave medially.

Pronotum subtrapezoidal, widest at base; lateral margins evenly curved and strongly convergent anteriad; anterior and posterior angles both rectangular; hypomeron carinate at base and strongly produced ventrally, anterior margin with a complete and fine marginal line; disc with a large cruciform and impunctate area, other portions with dense and large punctures, each puncture bearing an oblong seta, anterior and lateral margins with long recumbent setae.

Scutellum elongated triangular, apex rounded; longitudinal medial portions impunctate, other portions with dense and small punctures, each bearing an oblong seta.

Elytra oval, widest shortly after middle. Striae finely impressed, strial punctures dense and large; intervals weakly convex, with moderately dense and small punctures each bearing an oblong seta, usually interrupted by some impunctate sections, elytral surface sparsely bearing some large, spatulate or oblong setae, a single semi-erect long setae situated beside scutellum. Epipleura wide, ending after the distinctly curved external apical angle, with a row of dense and short setae, interspersed with some minute and oblong setae; elytral apex with an erect and short seta, posterior margin with a fine membranous rim composed of microtrichomes.

Ventral thoracic surface. Hypomeron with moderately dense punctures each bearing an oblong or spatulate seta; ventral mesothoracic surface densely punctate, with recumbent short setae; metasternum with dense and large punctures, each puncture bearing an erect short seta, medial portions with moderately dense, erect short setae; metepisternum and metacoxa punctate as metasternum, covering dense and elliptical setae, mixed with a few short setae laterally. Mesosternum between mesocoxae vertically produced and slightly narrower than width of the mesofemur. Ratio of length of metepisternum/ metacoxa: 1/ 1.34.

Abdomen. Abdominal ventrites with dense and large punctures, each bearing a spatulate seta, each ventrite with a sparse and transverse row of short spiniform setae. Ultimate ventrite medially almost as long as penultimate one, with scattered and long setae, spiniform setae devoid, posterior margin of ultimate ventrite with very dense and short setae medially. Pygidium moderately convex, with a fine midline, posterior margin weakly reflexed; surface with moderately dense and large punctures, each puncture bearing a large and oblong seta, interspersed with sparse and long setae, central area impunctate.

Femora. Profemur dull at dorsal third, with a row of moderately long setae near dorsal margin. Mesofemur dull, two longitudinal rows of sparse punctures each bearing a short seta, with a transverse ridge near anterior margin. Metafemur with sparse and small punctures, with two rows of large punctures at anterior margin and before midline, each puncture bearing a short seta; anterior margin moderately sharp, ventral posterior margin serrate at apical third, dorsal posterior margin completely serrate, several short setae situated between the latter two margins.

Tibiae. Protibia moderately long, bidentate, tibial teeth acute. Metatibia widest shortly before apex, ratio of width/ length: 1/ 3.96; dorsal margin carinate; lateral face longitudinally striolate and finely punctate, dorsally with two groups of spiniform setae not touching the dorsal carina, basal group at two fifths, distal group at two thirds of metatibial length, basal fifth with two short setae; ventral margin serrate except for basal quarter, with three long spiniform setae of which distal two are more distant; medial face impunctate; apex interiorly serrate, near tarsal articulation shallowly concave.

Tarsi. Protarsomeres short, pro- and mesotarsomeres with sparse and minute setae ventrally. Mesotarsomeres finely serrate ventrally. All metatarsomeres carinate laterally and serrate ventrally, metatarsomere 1 as long as following two tarsomeres combined and twice as long as dorsal tibial spur. Protarsal claws weakly asymmetric, basal tooth of outer claw wider and distinctly shorter than the distal one, that of inner claw truncate at apex, with a blunt, additional basal tooth. Basal teeth of meso- and metatarsal claws more acute than that of outer protarsal claw.

Aedeagus. Fig. 2E .

Variation. Female. Antennal club distinctly shorter, 0.6 times as long as remaining antennomeres combined; pygidium conically convex at disc; eyes smaller than in male, ratio diameter/ interocular width: 0.48; protarsal claws symmetric, basal tooth acute as distal one.

Measurements. Length: 9.7–10.5 mm in males (holotype 10.4 mm), 9.7–11.0 mm in females; length of elytra: 6.6–7.0 mm in males (holotype 6.8 mm), 6.3–7.2 mm in females; width: 5.4–5.8 mm in males (holotype 5.7 mm), 5.4–5.8 mm in females.

Diagnosis. The new species is easily characterized from all other Pachyserica species by its peculiar shape of male genitalia: the strongly asymmetric phallobase bearing a wide, rounded apical apophysis and the parameres are mesally entirely fused.

Etymology. The specific name is formed by the Latin words “ albus, -a, -um ” and “ punctatus, -a, -um ”. It is an allusion to the whitish markings on elytra aggregated with scale-like setae.

Figures

FIGURE 1. Habitus in dorsal view. A, Gastroserica (s. str.) mayunshui Zhao & Ahrens, new species, holotype; B, G. (s. str.) yunnanensis Liu, Ahrens, Bai & Yang, 2011, male (Guangdong); C, Pachyserica albopunctata Zhao & Ahrens, new species, holotype; D, P. albopunctata, female paratype; E, Amiserica lii Ahrens, 2003, female (Hunan); F, A. lii, male (Hunan). Scale bar = 5 mm.

FIGURE 2. Aedeagus. A, Gastroserica (s. str.) mayunshui Zhao &Ahrens, new species, holotype; B, G. (s. str.) yunnanensis Liu, Ahrens, Bai & Yang, 2011 (Guangdong); C, Amiserica lii Ahrens, 2003 (Hunan); D, M. aureola (Murayama, 1938) (Hunan); E, P. albopunctata Zhao & Ahrens, new species, holotype. a, aedeagus in left lateral view; b, parameres in dorsal view; c, aedeagus in right lateral view; d, aedeagus in dorsal view. Scale bar = 1 mm.