Serica (Taiwanoserica) liboyani 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 : 205-206

Serica (Taiwanoserica) liboyani Zhao & Ahrens , new species

( Figs 8C , 9C )

Type material examined. Holotype. ♂ ( SCAU), “ CHINA: Guizhou, Mt. Leigongshan, Lianhuaping, Xiannütang , 1555 m, 26°22′22.77″N, 108°11′52.23″E, 22–23.VII.2017 Ming-Zhi Zhao leg. at light” . Paratype. 1♀ ( CZMZ), “ CHINA: Guizhou, Mt. Leigongshan, Lianhuaping, Xiannütang , 1555 m, 26°22′22.77″N, 108°11′52.23″E, 22– 23.VII.2017 Ming-Zhi Zhao leg. at light” .

Description of the holotype. General. Body elongated ovoid, moderately convex, color dark brown, ventral surface including metacoxa with greenish toment; head (except for the dull frons), pronotum, scutellum and pygidium generally green, with strong coppery luster, brown integument irregular, elytra generally yellowish brown with irregular black patterns; legs reddish brown, palpi and antennae yellowish brown, shiny. Setae pale.

Head. Labroclypeus subtrapezoidal, distinctly wider than long, widest at base, ratio of maximum length/ width: 1/ 2.0; lateral margins almost straight, distinctly convergent anteriad, anterior angles blunt, anterior margin widely and shallowly concave; margins weakly reflexed; surface flat, with dense and coarse punctures and some short, erect setae; frontoclypeal suture finely incised, curved medially; smooth area anterior to eye large and flat, approximately 2.4 times as wide as long, base dull, with weak toment; ocular canthus short and slender (slightly shorter than 1/3 of ocular diameter), with a short terminal seta. Frons dull and flat, anterior third with dense and large punctures, otherwise sparsely and finely punctate, with some short, erect seta. Eyes moderately small, ratio diameter/ interocular width: 0.58. Antenna with ten antennomeres; antennomeres 6 slightly wider than long, antennomere 7 transverse and short; club straight, with three antennomeres, length subequal to combined length of remaining antennomeres. Mentum strongly and transversely elevated anteriorly. Labrum transverse, strongly produced, widely concave medially.

Pronotum subrectangular, widest at middle, lateral margins strongly reflexed; anterior angle distinctly produced and acute, posterior angles broadly rounded; hypomeron carinate at base but not produced ventrally; anterior margin with a fine marginal line, indistinct medially; surface with moderately dense and large punctures, punctures sometimes rather dense and each bearing a lanceolate seta, with a longitudinal and impunctate midline, also a smaller, transverse and impunctate area on each side of the disc; anterior and lateral margins with sparse and moderately long erect setae.

Scutellum large, triangular, apex somewhat rounded; basomedial and apical portions impunctate, otherwise with dense and large punctures and moderately dense and minute, scale-like setae.

Elytra elongated, widest shortly after middle. Striae distinctly impressed, strial punctures dense and large; intervals weakly convex, with moderately dense and large punctures, with a few large and lanceolate seta, dark patterns irregular and impunctate, humeral convexity dull. Epipleura ending shortly before moderately curved external apical angle of elytron, with a row of moderately dense and semi-erect short setae, elytral apex with a short seta, apical margin with a very fine membranous rim composed of microtrichomes.

Ventral thoracic surface and metacoxae with dense and large punctures each bearing a short seta, setae on medial portions of metasternum shorter, hypomeron sparsely setose. Mesosternum between mesocoxae slightly narrower than width of mesofemur. Ratio of length of metepisternum/ metacoxa: 1/ 1.36.

Abdomen. Abdominal ventrites with moderately dense and small punctures, each ventrite with a transverse row of punctures each bearing a semi-erect, short seta, penultimate ventrite medially with several moderately long setae; ultimate ventrite medially 0.75 times as long as penultimate one and with a tuft of moderately long setae and a transverse row of minute setae near posterior margin. Pygidium weakly convex, with impunctate midline not reaching apex, posterior margin moderately reflexed; surface with scattered and coarse punctures, dark patterns impunctate, most punctures bearing a short seta, with moderately long setae laterally and aggregated near apex.

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

Tibiae. Protibia moderately long, bidentate, mesial external margin weakly convex. Metatibia widest shortly before apex, ratio of width/ length: 1/ 3.75; dorsal margin not carinate; lateral face with scattered and small punctures, two groups of short and spiniform setae not touching the dorsal carina, basal group at middle, distal group shortly before three quarters of metatibial length, basally with several smaller setae; ventral margin serrate except for basal quarter, with three spiniform setae of which distal two are more distant, the first one distinctly thinner and shorter; medial face finely and sparsely punctate; apex interiorly serrate, near tarsal articulation bluntly truncate.

Tarsi. Protarsomeres short, pro- and mesotarsomeres with moderately dense and minute setae ventrally. Meso- and metatarsomeres serrate ventrally. Metatarsomeres not carinate laterally, first metatarsomere as long as following two tarsomeres combined and twice as long as dorsal tibial spur. Protarsal claws symmetric, basal tooth normally developed.

Male genitalia. Fig. 9C .

Variation. Female. Antennal club slightly shorter, 0.8 times as long as remaining antennomeres combined. Other features almost identical to male.

Measurements. Length: 7.3 mm in male holotype, 7.4 mm in female; length of elytra: 5.2 mm in male holotype, 5.2 mm in female; width: 3.9 mm in male holotype, 4.4 mm in female.

Diagnosis. Serica liboyani Zhao & Ahrens , new species is one of the most peculiar species of the subgenus Taiwanoserica . It differs from all other species by its parameres which are not devised into separate branches or lobes.

Etymology. The species name is dedicated to Mr. Bo-Yan Li, a good friend and teammate of the first author during the survey in Mount Leigongshan.

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.