Maladera hsui Ahrens, Fabrizi & Liu, 2021

Fabrizi, Silvia, Liu, Wan-Gang, Bai, Ming, Yang, Xing-Ke & Ahrens, Dirk, 2021, A monograph of the genus Maladera Mulsant & Rey, 1871 of China (Coleoptera: Scarabaeidae: Melolonthinae: Sericini), Zootaxa 4922 (1), pp. 1-400 : 38-40

Maladera hsui Ahrens, Fabrizi & Liu , sp. n.

Figures 7 A–D, 87

Type material examined. Holotype: ♂ “ China: Yunnan Prov. Da Li alt. 2100m 8/VII/2000 collr. Y.F. Hsu / 724 Sericini : Asia spec.“ ( ZFMK) . Paratypes: 1 ♂ “ China: Yunnan Prov. Da Li alt. 2100m 8/VII/2000 collr. Y.F. Hsu ” ( ZFMK) , 1 ♂ “ China pr. Yunnan Dali 19– 21.5.1993 R. Cervenka lgt.” ( ZFMK) , 1 ♂ “[ China] Yunnan, Pianma , 2011-V-9, N: 26.018, E: 98.625, 1970m/ LW-1075” ( ISAZ) .

Description. Length: 9.6 mm, length of elytra: 6.9 mm, width: 6.0 mm. Body short oval, dark reddish brown, antenna yellow, labroclypeus moderately shiny, remainder of dorsal surface dull, glabrous except for a few small setae on head and lateral margins of pronotum and elytra.

Labroclypeus trapezoidal, distinctly wider than long, widest at base, lateral margins straight and strongly convergent to moderately rounded anterior angles, lateral margin and ocular canthus producing an indistinct angle, margins weakly reflexed, anterior margin distinctly emarginate medially; surface transversely convex, moderately shiny, finely and very densely, rugosely punctate, distance between punctures smaller than their diameter, with a few erect setae anteriorly; frontoclypeal suture feebly incised and weakly curved; smooth area anterior to eye twice as wide as long; ocular canthus short and wide, finely scarcely punctate, with a single terminal seta. Frons dull, with fine, sparse punctures, glabrous except for a few setae beside eyes. Eyes small, ratio of diameter/ interocular width: 0.5. Antenna with ten antennomeres; club with three antennomeres slightly as long as remaining antennomeres combined. Mentum elevated and flattened anteriorly.

Pronotum transverse, widest at middle, lateral margins in basal half straight and nearly subparallel, in anterior half moderately convex and evenly narrowed towards strongly produced and sharp anterior angles; anterior margin weakly convex, with complete and fine marginal line, posterior angles blunt; basal margin without marginal line; surface moderately finely and densely punctate, punctures with microscopic setae only; anterior and lateral margins setose; hypomeron carinate but not produced ventrally. Scutellum wide, triangular, with fine and moderately dense punctures, without smooth midline.

Elytra oblong, widest at middle, striae weakly impressed, finely and sparsely punctate, intervals weakly convex, with fine, moderately dense and almost evenly distributed punctures; penultimate lateral interval with a few sparse fine, short setae, remainder of punctures with minute setae only; epipleural margin robust, ending at widely rounded external apical angle of elytra, epipleura sparsely setose, apical border narrowly membranous, apex covered with short microtrichomes.

Ventral surface dull, metasternum and metacoxa with large and dense punctures, sparsely setose; metacoxa glabrous except for numerous long setae laterally; abdominal sternites finely and densely punctate, some punctures with very short or minute setae, each sternite with a distinct transverse row of coarse punctures each bearing a short seta, penultimate sternite apically with a wide shiny smooth chitinous border of half sternite length. Mesosternum between mesocoxae as wide as mesofemur. Ratio of length of metepisternum/metacoxa: 1/1.67. Pygidium moderately convex, dull, finely and moderately densely punctate, glabrous except a few short setae apically.

Legs moderately wide; femora finely and sparsely punctate, with two longitudinal rows of setae. Metafemur wide, dull, anterior margin acute, lacking an adjacent serrated line, surface very sparsely and superficially punctate, anterior row of setae complete; posterior ventral margin feebly concave medially, moderately widened in apical half and not serrate apically, posterior margin dorsally not serrated, glabrous. Metatibia wide and short, widest just behind middle, ratio width/length: 1/2.96, dorsal margin sharply carinate, with two groups of spines, basal one at anterior third, apical one at two thirds of metatibial length, beside dorsal margin basally with one or two fine setae; lateral face weakly longitudinally convex, nearly entirely impunctate; ventral margin finely serrate, with four strong spines of which apical one is more distant; medial face impunctate, apex shallowly concave interiorly near tarsal articulation. Tarsomeres impunctate dorsally, with sparse, short setae ventrally; metatarsomeres with a strongly serrated longitudinal ridge and a strong, smooth carina beside it, first metatarsomere distinctly shorter than following two tarsomeres combined and slightly longer than dorsal tibial spur. Protibia short, bidentate. All claws symmetrical, feebly curved and long, with normally developed basal tooth.

Aedeagus: Fig. 6 A–C. Habitus: Fig. 6D . Female unknown.

Diagnosis. Maladera hsui Ahrens, Fabrizi & Liu , sp. n. differs from the other Hemiserica species of China in the following features: body size larger (> 9 mm); the labroclypeus coarsely and rugosely punctate, its surface strongly convex; and the dorsoapical median emargination of phallobase is deep and narrow.

Etymology. The new species is named after one of its collectors, Y.F. Hsu (noun in the genitive singular case).

Variation. Length: 9.0– 9.6 mm, length of elytra: 6.6–6.9 mm, width: 4.8–6.0 mm.

Distribution. See map ( Fig. 87 ) and Table 1.

Figures

FIGURE 6. A–D: Maladera rufopaca Ahrens, Fabrizi & Liu, sp. n. (paratype); E–H: M. fangchengensis Ahrens, Fabrizi & Liu, sp. n. (holotype). A, E: aedeagus, left side lateral view; C, G: aedeagus, right side lateral view; B, F: parameres, dorsal view; D, H: habitus. Scale: 0.5 mm. Habitus not to scale.

FIGURE 7. A–D: Maladera hsui Ahrens, Fabrizi & Liu, sp. n. (paratype); E–H: M. eshanensis Ahrens, Fabrizi & Liu, sp. n. (holotype). A, E: aedeagus, left side lateral view; C, G: aedeagus, right side lateral view; B, F: parameres, dorsal view; D, H: habitus. Scale: 0.5 mm. Habitus not to scale.

FIGURE 87. Distribution of the subgenus Hemiserica: Maladera eshanensis sp. n., M. fangchengensis sp. n., M. hsui sp. n., M. rufopaca sp. n..