Maladera riberai 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 : 66-68

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

Figures 13 A–D, 93

Type material examined. Holotype ♂ “ China—Shaanxi, Daba Shan, Shou Man vill., 32°14’N, 108°34’E, 25.v.- 14.vi.2000, 1000m, Siniaev & Plutenko leg./ 1072 Sericini Asia spec.” ( CP).

Description. Length: 9.6 mm, length of elytra: 6.5 mm, width: 6.0 mm. Body oval, dark brown, antenna yellow, labroclypeus shiny, remainder of dorsal surface dull, glabrous, except for a few small setae on the head and elytra.

Labroclypeus subtrapezoidal, distinctly wider than long, widest at base, lateral margins weakly convex and convergent to strongly rounded anterior angles, lateral margin and ocular canthus producing a distinct blunt angle, margins moderately reflexed; anterior margin very shallowly emarginate medially; surface convex medially, weakly shiny, coarsely punctate, with a few short, erect setae; frontoclypeal suture feebly impressed and weakly curved medially; smooth area in front of eye approximately twice as wide as long; ocular canthus short and moderately wide, finely punctate, with a short terminal seta. Frons with fine, moderately dense punctures, glabrous except for a few setae beside eyes and frontoclypeal suture as well as on disc. Eyes small, ratio diameter/ interocular width: 0.57. Antenna yellow, with 10 antennomeres; club with three antennomeres, little longer than remaining antennomeres combined. Mentum anteriorly elevated and flattened.

Pronotum widest at base, lateral margins weakly and evenly convex and convergent anteriorly, anterior angles distinctly produced and sharp, anterior margin weakly convex, marginal line widely interrupted medially; surface moderately finely and densely punctate, with minute setae in punctures; anterior and lateral margins sparsely setose. Scutellum wide, triangular, with fine and moderately dense punctures, each bearing a single very minute seta.

Elytra oblong, widest at middle, striae distinctly impressed, finely and densely punctate, odd intervals moderately convex, with a few erect setae, even intervals nearly flat, with fine, moderately dense punctures concentrated along striae, with minute setae in punctures; epipleural margin robust, ending at the weakly convex external apical angle of elytra, epipleura densely setose, apical border membraneous, with a very fine rime of short microtrichomes.

Ventral surface dull, thorax and metacoxa with large dense punctures, sparsely setose, metacoxa glabrous except for a few long setae laterally. Abdominal sternites, in addition to generally distributed fine and moderately dense punctures, with a distinct transverse row of coarse punctures each bearing a short and robust seta, some punctures with microscopic setae, penultimate sternite apically with a shiny smooth chitinous border, which is a quarter as long as sternite. Mesosternum between mesocoxae as wide as mesofemur. Ratio of length of metepisternum/ metacoxa: 1/ 1.66. Pygidium moderately convex, finely and densely punctate, without smooth midline, punctures with minute setae and with a few long setae along apical margin.

Legs moderately narrow and long; femora with two longitudinal rows of setae, finely and moderately densely punctate. Metafemur dull, anterior margin acute, lacking an adjacent serrated line, posterior ventral margin medially straight, weakly widened in apical half and not serrate, posterior dorsal margin not serrated, finely setose. Metatibia moderately wide and long, widest at apex, ratio width/ length: 1/ 3.4, dorsally sharply carinate, with two groups of spines, basal one at middle, apical one at four fifths of metatibial length, basally with a few punctures, each bearing short single spines; lateral face shiny and longitudinally convex, with sparse and fine punctures, with minute setae in punctures; ventral margin serrate, with four strong equidistant spines; medial face impunctate, apex interiorly near tarsal articulation shallowly concave. Tarsomeres impunctate dorsally, ventrally with sparse, short setae; metatarsomeres ventrally with a strongly serrated ridge, beside it with smooth subventral longitudinal carina; first metatarsomere shorter than following two tarsomeres combined and little longer than dorsal tibial spur. Protibia short, bidentate. Protarsal claws asymmetrical, basal tooth of interior claw convexly rounded at tip, basal tooth of external claw with normally developed sharply truncate basal tooth.

Aedeagus: Fig. 13 A–C. Habitus: Fig. 13D . Female unknown.

Diagnosis. Maladera riberai Ahrens, Fabrizi & Liu , sp. n. is very similar to M. xingkei Ahrens, Fabrizi & Liu , sp. n. in shape of the aedeagus, differing in having the right paramere straight and the left paramere fused with the apex of the phallobase.

Etymology. The new species is dedicated to Ignacio Ribera Galán (Barcelona), well known beetle specialist and friend, who passed away this year to much early (noun in the genitive singular case).

Distribution. See map ( Fig. 93 ) and Table 1.

Figures

FIGURE 13. A–D: Maladera riberai Ahrens, Fabrizi & Liu, sp. n. (holotype); E–H: M. guangdongana Ahrens, Fabrizi & Liu, sp. n. 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 93. Distribution of the subgenus Omaladera: Maladera perniciosa (Brenske, 1898), M. pseudohongkongica Ahrens & Fabrizi, 2016, M. riberai sp. n., M. shiniushanensis sp. n..