Microserica simplex Arrow, 1946

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 : 31-33

Microserica simplex Arrow, 1946

Figs. 10A–D , 27

Microserica simplex Arrow, 1946: 273 .

Type material examined. Syntypes: 1 Ô “ Burma Myndaik 4500 ft. 5.V.18 A. G. R. Coll. / Microserica simplex Type Arrow” ( BMNH), 1 ♀ “ Burma Myndaik 4500 ft. 5.V.18 A. G. R. Coll. ” ( BMNH) .

Additional material examined. Thailand. 18 ex. “NE Thailand 1.-15.5[?]. 1991 Mae Hong Son Ban Huai Po 800-1600 m S. Bily leg.” ( NHMB) , 10 ex. “NE Thailand 8.-17.V.1992 Mae Hong Son Ban Huai Po 1600 m, S. Bily leg.” ( NHMB) , 43 ex. “NW Thailand, 19.19N, 97.97E Mae Hong Son, 1991 Ban Huai Po, 1600-2000 m 17.-23.5., L. Dembicky leg.” ( NHMW) , 2 ÔÔ “NW Thailand 9.- 16.5.1991 Mae Hong Son, Ban Huai Po 1600- 2000 m J. Horák leg.” ( ZFMK) , 7 ex. “ Thai 28/4.-6/5.91 Umphang river 1000 m 16°07‘N 99°99‘E David Kral lgt.” ( CK) , 4 ex. “ N. Thailand Mae Hong Son, Ban Huai Po 9.- 16.5.1991 1600-2000 m I. Horak lgt.” ( ZFMK) , 2 ex. “NW Thailand 19.19N, 97.59E Mae Hong Son 1991 Ban Huai Po 1600-1900m 17.-23.5., L. Dembicky leg.” ( NHMB) , 1 ex. “ Thailand Bor. Occ. 30.04.- 14.05.1991 Mae Hong Son env. Ban Huai Po, 1800m, Jan Farkac leg.” ( NHMB) , 1 ex. “ Thai 17.-24.V.1991 Chiang Dao 1000 m 19°25‘N 98°52‘E Vit Kuban leg.“ ( CN) , 1 ex. “ Thailand, 7.-12.V.1996 Mae Hong Son Prov. Soppong 1500 m 19°27‘N 98°20‘E lgt. S. Becvar ” ( ZFMK) , 2 ÔÔ “ Thailand bor. Hang Dong 6.1990 lgt. Wimmer” ( ZFMK) , 3 ÔÔ “ Thailand centr. Pa-Sak Fl. IX-86 Rhtchabunn- 600m ” ( ZFMK) . China. 3 ex. (Ô) [ China ] “ Yunnan 1800-2000 m 25.04N 101.55E Yipinglang 17-20.6. Vit Kubáň leg. 1994 / CS 76” ( CP) , 2 ÔÔ [ China ] “Mengzhe, Xishuangbanna, Yunnan, 15.VI.1958, 1200m, leg. Wang Shuyong / LW-380” ( IZAS) , 1 Ô “ Huanian , 15.VI.1983 ” ( IZAS) . Laos. 334 ex. “NE-Laos: Hua Phan prov., Ban Saleui, Phou Pan ( Mt. ) - 20°12’N, 104°01’E; 14.iv.-15.v.2012; 1300-1900m; leg. C. Holzschuh Ankauf ZFMK Bonn 2012/13” ( ZFMK) , 760 ex. “NE-Laos: Hua Phan prov., Ban Saleui, Phou Pan ( Mt. ) - 20°12’N, 104°01’E; 11.iv.-15.v.2012; 1300- 1900m; leg. C. Holzschuh Ankauf ZFMK Bonn 2012” ( ZFMK) , 10 ex. “NE-Laos: Hua Phan prov., Ban Saleui, Phou Pan ( Mt. ) - 20°12’N, 104°01’E; 1300-1900m; 01.-31.V.2011; leg. C. Holzschuh Ankauf ZFMK Bonn 2011” ( ZFMK) , 2 ex. “Laos-NE Hua Phan prov., 20°12’N, 104°01’E, Phu Phan Mt. , 1500-1900m, 17.5.- 3.6.2007, leg. C. Holzschuh ” ( ZFMK) , 2 ex. “Laos-NE Hua Phan prov., 20°12’N, 104°01’E, Phu Phan Mt. , 1500-1900m, 17.5.- 3.6.2007, leg. Vit. Kuban ” ( ZFMK) , 1 Ô “X-DA4933 / X- DA4933 LAOS Hua Phua prov., Ban Saluei, Phou Pan ( Mt. ) 20°12’N, 104°01’E 2.iv.2014 leg. C. Holzschuh – ZFMK Ankauf 2014 Microserica simplex ” ( ZFMK) , 1 Ô “X-DA4932 / X- DA4932 LAOS Hua Phua prov., Ban Saluei, Phou Pan ( Mt. ) 20°12’N, 104°01’E 2.iv.2014 leg. C. Holzschuh – ZFMK Ankauf 2014 Microserica simplex ” ( ZFMK) , 1 Ô “X-DA4718 / X- DA4718 LAOS Hua Phua prov., Ban Saluei, Phou Pan ( Mt. ) 20°12’N, 104°01’E 15.-30.iv.2014 leg. C. Holzschuh – ZFMK Ankauf 2014 Microserica simplex ” ( ZFMK) , 1 Ô “X-DA4711 / X- DA4711 LAOS Hua Phua prov., Ban Saluei, Phou Pan ( Mt. ) 20°12’N, 104°01’E 15.-30.iv.2014 leg. C. Holzschuh – ZFMK Ankauf 2014 Microserica simplex ” ( ZFMK) , 1 Ô “X-DA4710 / X- DA4710 LAOS Hua Phua prov., Ban Saluei, Phou Pan ( Mt. ) 20°12’N, 104°01’E 15.-30.iv.2014 leg. C. Holzschuh – ZFMK Ankauf 2014 Microserica simplex ” ( ZFMK) .

Redescription. Length: 6.4 mm, length of elytra: 3.8 mm, width: 3.6 mm. Body oval, ventral face, antennal funiculus, and legs yellowish brown, abdomen and antennal club brown, dorsal surface reddish brown, dorsal surface dull, sometimes partly iridescent shiny, nearly glabrous.

Labroclypeus wider than long, widest at middle, lateral margins in basal half subparallel, strongly convex anteriorly and convergent to strongly rounded anterior angles; anterior margin distinctly emarginate medially, margins weakly reflexed; lateral margins and ocular canthus produce a blunt angle; surface shiny, medially convex, finely and coarsely, densely punctate, with numerous long, erect setae; frontoclypeal suture finely incised and bent medially. Frons dull, with sparse, fine punctures, beside eyes and behind frontoclypeal suture with a few single short setae, otherwise 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 moderately small, ratio of diameter/interocular width: 0.58. Antenna with ten antennomeres; club composed of six antennomeres, reflexed, 1.7 times as long as remaining antennomeres combined. Mentum elevated and slightly flattened anteriorly.

Pronotum wide, widest at base, lateral margins evenly convex and convergent to blunt, moderately produced anterior angles, posterior angles blunt. Anterior margin of pronotum weakly convex, with fine and complete marginal line; basal marginal line absent; surface finely and densely punctate, with minute setae in punctures, lateral and lateral anterior margins densely 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 moderately dense 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: 1/1.67. 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, only weakly 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: 1/3.0; dorsal margin sharply carinate, with two groups of spines, basal group at one third, apical one at three quarter 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 glabrous, with a strongly serrated ridge ventrally and a parallel subventral smooth carina immediately beside it; first metatarsomere little shorter than 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. 10A–C . Habitus: Fig. 10D .

Variation. Female: Antennal club composed of three antennomeres, as long as remaining antennomeres combined.

Figures

FIGURE 10. A–D: Microserica simplex Arrow, 1946 (Thailand: Mae Hing Son). A: Aedeagus, left side lateral view; C: Aedeagus, right side lateral view; B: Parameres, dorsal view; D: Habitus (not to scale). Scale: 0.5 mm.

FIGURE 27. Distribution of the Microserica simplex group.