Maladera liaochengensis 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 : 175-176

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

Figures 39 E–H, 107

Type material examined. Holotype: ♂ “[ China] Caitun , Liaocheng, No. 4D-30, 29.VI.1980 ” ( IZAS). Paratypes: 1 ♂ “[ China] Wuqiang, Hebei, 23-25.VII.2000, leg. Wang Zhijian ” ( HBUM), 1 ♂, 1 ♀ “[ China] Xiangshui, Boluo, Guangdong, 30, 31.V.1965, leg. Zhang Youwei ” ( IZAS), 2 ♂♂ “[ China] Xiguang Forestry Farm, Tianjin, 15.VI.1965 ” ( IZAS, ZFMK).

Description. Length: 7.3 mm, length of elytra: 5.4 mm, width: 3.9 mm. Body oblong-oval, yellowish brown, antenna yellow, shiny, labroclypeus shiny, dorsal face nearly glabrous.

Labroclypeus wide and subtrapezoidal, widest at base, lateral margins weakly convex and strongly convergent anteriorly, anterior angles moderately rounded, anterior margin weakly emarginate, margins weakly reflexed; lateral margin and ocular canthus produce an indistinct angle; surface flat, finely, densely punctate, with a few long setae anteriorly; frontoclypeal suture indistinctly incised, weakly curved; smooth area anterior to eye convex, twice as wide as long; ocular canthus short and narrow (1/4 of ocular diameter), finely densely punctate, with a terminal seta. Frons with dense and fine punctures, glabrous. Eyes small, ratio diameter/ interocular width: 0.6. Antenna missing in holotype. Mentum elevated and slightly flattened anteriorly.

Pronotum transverse, widest at base, lateral margins evenly convex and convergent anteriorly, anterior angles distinctly produced and sharp, posterior angles blunt; anterior margin straight, with fine marginal line, base without marginal line; surface finely and densely punctate, with minute setae in punctures being as long as puncture diameter, otherwise glabrous; anterior and lateral margin sparsely setose; hypomeron carinate, not produced ventrally. Scutellum wide, triangular, with fine, dense punctures.

Elytra widest at middle, striae finely impressed, finely and densely punctate, intervals flat, with fine, moderately dense punctures and with minute setae in punctures, penultimate lateral interval with a few single setae; epipleural margin robust, ending at apical external angle of elytra, epipleura densely setose; apical border of elytra membraneous, with a very fine rim of microtrichomes (visible at ca 100x magnification).

Ventral surface shiny, finely and densely punctate, metasternum including disc sparsely setose; metacoxa glabrous, 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: 1/1.67. Pygidium weakly convex, weakly shiny, finely and densely punctate, without smooth midline, with a few long but fine setae along apical margin.

Legs short and wide, shiny; femora with two longitudinal rows of setae, finely and sparsely punctate. Anterior margin of metafemur acute, without adjacent continuous serrated line, anterior row of setae complete; posterior ventral margin smooth, weakly widened at ventral apex, dorsal posterior margin smooth, neither serrate, with a few single long setae. Metatibia short and moderately wide, widest at middle, ratio of width/length: 1/2.6, sharply carinate dorsally, with two groups of spines, basal group at one third, apical group at two thirds of metatibial length, in basal half with a few short and robust single setae; lateral face longitudinally convex, except a few superficial punctures on sides and base smooth and glabrous; ventral margin finely serrate, with five equidistant robust setae; medial face smooth and glabrous; apex finely serrate, concavely emarginate interiorly near tarsal articulation. Tarsomeres dorsally impunctate, glabrous, neither laterally nor dorsally carinate, moderately setose ventrally; metatarsomeres with a strongly serrated ridge ventrally and a smooth subventral longitudinal carina, glabrous; first metatarsomere distinctly shorter than following two tarsomeres combined and distinctly longer than dorsal tibial spur. Protibia short, bidentate; anterior claws symmetrical, basal tooth of both claws bluntly truncate at apex.

Aedeagus: Fig. 39 E–G. Habitus: Fig. 39H .

Diagnosis. Maladera liaochengensis Ahrens, Fabrizi & Liu , sp. n. differs from M. detersa (Erichson) in having parameres longer than the phallobase.

Etymology. The new species is named after the type locality Liaocheng (adjective in nominative singular).

Variation. Length: 7.3–8.2 mm, length of elytra: 5.4–5.9 mm, width: 3.8–4.6 mm. Antenna in male paratypes with ten antennomeres, club composed of three antennomeres and straight, as long as remaining antennomeres combined. Female: eyes as large as in male, antennal club little shorter than remaining antennomeres combined; pygidium weakly convex.

Distribution. See map ( Fig. 107 ) and Table 1.

Figures

FIGURE 39. A–D: Maladera kalawensis Ahrens, Fabrizi & Liu, sp. n. (holotype); E–H: M. liaochengensis Ahrens, Fabrizi & Liu, sp. n. (holotype); I–L: M. paradetersa Ahrens, Fabrizi & Liu, sp. n. (holotype). A, E, I: aedeagus, left side lateral view; C, G, K: aedeagus, right side lateral view; B, F, J: parameres, dorsal view; D, H, L: habitus. Scale: 0.5 mm. Habitus not to scale.

FIGURE 107. Distribution of the Maladera detersa group: Maladera detersa (Erichson, 1834), M. kalawensis sp. n., M. liaochengensis sp. n., M. paradetersa sp. n. (not precisely localized collection site indicated by a “?”).