Maladera guomenshanica 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 : 146-148

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

Figures 32 A–D, 102

Type material examined. Holotype: ♂ “[ China] Yunnan, Nabanhe Nature Reserve, Guomenshan , 2009-IV-26 / LW-1165” ( ISAZ) . Paratype: 1 ♂ “[ China] Yunnan, Nabanhe Nature Reserve, Guomenshan , 2009-IV-26 / LW-1165bis” ( ZFMK) .

Description. Length: 9.0 mm, length of elytra: 6.2 mm, width: 5.2 mm. Body oblong-oval, yellowish brown, dull, labroclypeus shiny, with a few long setae on head, pronotum and elytra.

Labroclypeus short and wide, subtrapezoidal, widest at base, lateral margins convex and strongly convergent anteriorly, anterior angles strongly rounded, anterior margin shallowly emarginate, margins strongly reflexed; lateral margin and ocular canthus produce an indistinct angle; surface distinctly carinate along middle, finely, densely punctate, with a few erect, long setae; frontoclypeal suture distinctly incised, bluntly angled medially; smooth area anterior to eye very small and flat, three times as wide as long; ocular canthus short and wide (1/3 of ocular diameter), finely densely punctate, with a terminal seta. Frons dull, with sparse and fine punctures, with robust and long setae beside eyes and behind frontoclypeal suture. Eyes moderately small, ratio diameter/ interocular width: 0.57. Antenna with ten antennomeres; club with three antennomeres and straight, as long as remaining antennomeres combined. Mentum elevated and slightly flattened anteriorly.

Pronotum moderately transverse, widest shortly before base, lateral margins evenly convex and convergent anteriorly and posteriorly, anterior angles distinctly produced and sharp, posterior angles blunt, rounded at tip; anterior margin straight, with fine marginal line, base without marginal line; surface moderately finely and densely punctate, with minute setae in punctures and a very few long, semi-erect setae in coarse punctures on lateral disc (abraded in holotype, but large punctures visible); anterior and lateral margin robustly densely setose; hypomeron carinate, not produced ventrally. Scutellum wide, triangular, with fine, moderately dense punctures.

Elytra widest in posterior third, striae finely impressed, finely and densely punctate, intervals weakly convex, second one flat, with fine, moderately dense punctures and with minute setae in punctures, odd intervals with numerous single long setae in darker coarse punctures; epipleural margin robust, ending half of elytra, epipleura sparsely setose; apical border of elytra membraneous, with a fine rim of microtrichomes (visible at ca 100x magnification).

Ventral surface dull, finely and densely punctate, nearly glabrous, metasternal disc sparsely covered with fine, short setae; metacoxa with a few longer setae laterally. Abdominal sternites finely and densely punctate, punctures with minute setae, each sternite with a transverse row of punctures each bearing a fine seta. Mesosternum between mesocoxae as wide as mesofemur. Ratio of length of metepisternum/metacoxa: 1/1.98. Pygidium weakly convex, dull, finely and moderately densely punctate, without smooth midline, with a few long setae along apical margin, otherwise only with minute setae in punctures.

Legs short and wide, dull; femora with two longitudinal rows of setae, finely and sparsely punctate. Anterior margin of metafemur acute, without adjacent serrated line, anterior row of setae completely reduced; posterior ventral margin smooth, strongly widened at ventral apex, dorsal posterior margin smooth, neither serrate, glabrous. Metatibia short and wide, widest at middle, ratio of width/length: 1/2.4, sharply carinate dorsally, with two groups of spines, basal group at middle, apical group at three quarters of metatibial length, in basal half with a few short and robust single setae; lateral face longitudinally convex, superficially and sparsely punctate, along midline widely smooth, glabrous; ventral margin finely serrate, with four equidistant robust setae; medial face smooth and glabrous; apex finely serrate, shallowly emarginate interiorly near tarsal articulation. Tarsomeres dorsally impunctate, glabrous, neither laterally nor dorsally carinate, moderately setose ventrally; metatarsomeres lacking in holotype. Protibia moderately long, bidentate; anterior claws symmetrical, basal tooth of both claws bluntly truncate at apex.

Aedeagus: Fig. 32 A–C. Habitus: Fig. 32D . Female unknown.

Diagnosis. Maladera guomenshanica Ahrens, Fabrizi & Liu , sp. n. differs from M. aureola (Murayama) in having longer parameres, and denser setae on the disc of pronotum and elytra.

Variation. Length: 9.0– 9.2 mm, length of elytra: 6.2–6.6 mm, width: 5.0– 5.2 mm. Metatarsomeres of paratype with a strongly serrated ridge ventrally and a smooth subventral longitudinal carina, glabrous; first metatarsomere distinctly shorter than following two tarsomeres combined and slightly longer than dorsal tibial spur.

Etymology. The name of the new species (adjective in the nominative singular) is derived from its type locality, Guomenshan.

Distribution. See map ( Fig. 102 ) and Table 1.

Figures

FIGURE 32. A–D: Maladera guomenshanica Ahrens, Fabrizi & Liu, sp. n. (holotype); E–H: M. hansmalickyi Ahrens, Fabrizi & Liu, sp. n.; I–M: M. jaintiaensis Ahrens & Fabrizi, 2016 (holotype). A, E, I: aedeagus, left side lateral view; C, G, L: aedeagus, right side lateral view; B, F, J: parameres, dorsal view; K: parameres, ventral view;D, H, M: habitus. Scale: 0.5 mm. Habitus not to scale.;

FIGURE 102. Distribution of the Maladera thomsoni group: Maladera apicalis sp. n., M.aureola (Murayama, 1938), M. botrytibia Nomura, 1974, M. guomenshanica sp. n., M. hansmalickyi sp. n..