Microserica parasimplex Ahrens, Lukic

Ahrens, Dirk, Liu, Wangang, Lukic, Daniel & Bai, Ming, 2023, A taxonomic review of Microserica Brenske, 1894 from continental Asia (Coleoptera: Scarabaeidae: Melolonthinae: Sericini), Zootaxa 5241 (1), pp. 1-115 : 36-37

Microserica parasimplex Ahrens, Lukic & Liu, new species

Figs. 12A–I , 27

Type material examined. Holotype: Ô “ LAOS, Xieng Khouang prov., 19°37–8’N, 103°20’E, Phonsavan (30 km NE) Phou Sane Mt. , 1420 m, 10-30.v.2009, Z. Kraus leg. / NHMB Basel, NMPC Prague, Laos 2009, Expedition: M. Brancucci, M. Geiser, Z. Kraus, D. Hauck, V. Kubáň / 1095 Sericini Asia spec.” ( NHMB) . Paratypes: Thailand: 1 Ô “THAI 21.-26.V.1993 Namuang Pacholatko & Dembicky leg. / TS 102 / 19 Sericini Asia spec.” ( CP) , 3 ÔÔ, 1 ♀ “ Phu Rua NP (900m alt.), Loei P. NE Thai. 26-30.IV.2006 Takakuwa, M. leg.” ( ZFMK) , 1 Ô “ Khak Ngam (820m) Phu Rua , Loei, NE Thai. 21-23.V.2004 Takakuwa, M. leg.” ( ZFMK) . Laos: 3 ÔÔ, 1 ♀ “ LAOS P.D.R., Xieng Khowang 14-20. May 1994 K. Miura leg.” ( ZFMK) .

Description of holotype. Length: 5.2 mm, length of elytra: 3.4 mm, width: 3.1 mm. Body oval, yellowish brown, frons and partly pronotum with some iridescent-greenish shine, antennal club at apex brown, dorsal surface iridescent, partly dull, nearly glabrous.

Labroclypeus little wider than long, widest at base, lateral margins convex and convergent to strongly rounded anterior angles; anterior margin weakly emarginate medially, margins weakly reflexed; lateral margins and ocular canthus produce a blunt angle; surface shiny, weakly convex, finely and coarsely, densely punctate, with numerous long, erect setae; frontoclypeal suture finely incised and bent medially. Frons with sparse, fine punctures, with a few longer setae beside eyes, otherwise with minute setae in punctures or glabrous. Smooth area in front of eyes 1.5 times as wide as long. Ocular canthus narrow and moderately long (1/3 of ocular width), sparsely finely punctate, with a terminal seta. Eyes small, ratio of diameter/interocular width: 0.49. Antenna with ten antennomeres; club composed of six antennomeres, straight, 1.5 times as long as remaining antennomeres combined. Mentum elevated and slightly flattened anteriorly.

Pronotum wide, widest shortly before base, lateral margins evenly convex and convergent to blunt, moderately produced anterior angles, posterior angles blunt. Anterior margin of pronotum straight, with robust and complete marginal line; basal marginal line absent; surface finely and densely punctate, with minute setae in punctures, anterior and lateral anterior margins sparsely setose. Hypomeron carinate, weakly produced ventrally. Scutellum triangular, finely and densely punctate, on midline impunctate.

Elytra short oval, widest at middle, striae distinctly impressed, finely and densely punctate, intervals convex, with fine and sparse punctures concentrated along striae, with minute setae in punctures, odd intervals with a few sparse short setae; epipleural edge robust, ending at slightly rounded external apical angle of elytra, epipleura densely setose, apical border chitinous, without a fringe of short microtrichomes (visible at ca 100x magnification).

Ventral surface dull, finely and densely punctate, metasternum sparsely covered with fine, short, or very minute setae; metacoxa glabrous, with a few single setae laterally. Mesosternum between mesocoxae as wide as mesofemur. Ratio of length of metepisternum/metacoxa: 1/1.81. Abdominal sternites finely punctate, with a transverse row of coarse punctures, each bearing a robust seta. Pygidium strongly convex and dull, with mixed finer and larger punctures, without smooth midline, with numerous short setae and a few longer in the larger punctures.

Legs moderately wide; femora finely and sparsely punctate, with two longitudinal rows of longer setae. Metafemur moderately shiny, anterior margin acute, without submarginal serrated line; anterior row of seta-bearing punctures present; ventral posterior margin finely serrate at apex, distinctly widened in apical half, dorsal posterior margin serrate, with a few short setae basally. Metatibia moderately long and wide, widest at middle, ratio width/ length: 1/2.79; dorsal margin sharply carinate, with two groups of spines, basal group at one third, apical one at two thirds of metatibial length, in basal third with a few robust single setae; lateral face longitudinally convex, finely and sparsely punctate, along midline smooth, with minute setae in punctures; ventral edge finely serrate, with three robust equidistant setae; medial face smooth, apex interiorly near tarsal articulation bluntly truncate. Tarsomeres with fine, sparse setae ventrally, neither laterally nor dorsally carinate, dorsally smooth; metatarsomeres with a strongly serrated ridge ventrally and a parallel subventral smooth carina immediately beside it; first metatarsomere as long as following two tarsomeres combined, twice as long as dorsal tibial spur. Protibia short, bidentate; anterior claws symmetrical, basal tooth of both claws bluntly truncate at apex.

Aedeagus: Fig. 12 A-C, E–H. Habitus: Fig. 12D, I . Female unknown.

Diagnosis. Microserica parasimplex Ahrens, Lukic & Liu, new species is in shape of aedeagus most similar to is in external appearance and shape of aedeagus most similar to Microserica allovarians Ahrens, Lukic & Liu, new species. Microserica parasimplex Ahrens, Lukic & Liu, new species differs by the lacking basidorsal process of the right paramere, the left paramere is dorsally enlarged and covers almost completely the right one.

Etymology. The species name is derived from the combined Greek prefix “ para -” (false) and the species name “ simplex ”, with reference to the certain similarity to Mic. simplex .

Variation. Length: 4.7–5.2 mm, length of elytra: 3.0– 3.3 mm, width:3.0– 3.1 mm.The species varies from almost entire dark (black) to completely yellow. Female: yellow, antennal club short, composed of three antennomeres, little shorter than remaining antennomeres combined; pygidium flat, eyes smaller than in male.

Figures

FIGURE 12. A–D: Microserica parasimplex Ahrens, Lukic & Liu, new species (holotype); E–I: Mic. parasimplex Ahrens, Lukic & Liu, new species (paratype). A, E: Aedeagus, left side lateral view; C, H: Aedeagus, right side lateral view; B, F: Parameres, dorsal view; G: Parameres, dorsolateral view; D, I: Habitus (not to scale). Scale: 0.5 mm.

FIGURE 27. Distribution of the Microserica simplex group.