Amiserica rufidula Nomura, 1974

Ahrens, Dirk, Liu, Wangang, Pham, Phu Van & Fabrizi, Silvia, 2021, An overview on the genus Amiserica Nomura, 1974 (Coleoptera: Scarabaeidae: Melolonthinae: Sericini), Zootaxa 5050 (1), pp. 1-63 : 7-8

Amiserica rufidula Nomura, 1974

Figures 1A–D , 15

Amiserica rufidula Nomura, 1974: 84 ; Ahrens 2002: 54, 2006b: 229, 2007: 11; Ahrens & Bezděk 2016: 282.

Material examined. 5 ♀♀ “ Taiwan: Tao Yuan Co. 65 km N Crossing Highway alt. 1400 m 28.VIII.1993 Collr. C. C. Chen” ( ZFMK) , 1 ex. “NE Taiwan: I Lan Co. Tai Ping Shan, alt. 1700 m 1/VII/1991 Coll. C. H. Tseng ” ( ZFMK) , 1 ex. “ Taiwan: Prov. Nan-Tou, Tayuling 2550 m, 07–08.1996 leg. Gy. Fabian & F. Nemes ” ( HNHM) , 1 ♂ “Taiwan, Hualien Co. Rei Suei, logging road, 1500 m, 23°21’09N, 121°16’49E 31.VIII.2003, G. Csorba & Z. Korsós” ( HNHM) .

Redescription of male. Length: 6.6 mm, length of elytra: 4.4 mm, width: 3.4 mm. Body oblong, dark reddish brown, surface dull, labroclypeus shiny, antenna yellowish brown, dorsal surface almost glabrous.

Labroclypeus subtrapezoidal, widest at base, lateral margins weakly convex and convergent to strongly rounded anterior angles, lateral border and ocular canthus producing a distinct obtuse angle; anterior margin weakly emarginate medially, margins weakly reflexed; surface flat and shiny, coarsely and densely punctate, with a few long erect setae in transverse line at middle; frontoclypeal suture indistinctly impressed and angled medially; smooth area anterior to eye 1.5 times as wide as long. Ocular canthus moderately long and narrow, finely and sparsely punctate, with a short terminal seta, equal to 1/3 of ocular diameter. Frons dull, finely and moderately densely punctate, with sparse long setae beside eyes and on disc. Eyes large, ratio of diameter/interocular width: 0.8. Antenna with ten antennomeres, club with three antennomeres, slightly reflexed externally, twice as long as remaining antennomeres combined. Mentum elevated and flattened anteriorly.

Pronotum widest at base, lateral margins in basal half subparallel, in anterior part strongly curved and convergent to moderately produced and nearly blunt anterior angles, posterior angles nearly rectangular; anterior margin distinctly convex, with the marginal line narrowly interrupted at middle; basal margin without marginal line; surface with dense and coarse punctures each bearing a minute seta, otherwise glabrous; anterior and lateral borders sparsely setose; hypomeron carinate, basal margin of hypomeron not produced ventrally. Scutellum triangular, apex sharp, with coarse and moderately dense punctures, smooth on basal midline, punctures with minute setae only.

Elytra oblong, widest shortly behind middle, striae distinctly impressed, with fine and dense punctures; intervals moderately convex, with fine and moderately dense punctures concentrated along striae, punctures with minute setae only, on penultimate lateral interval with a few long erect fine setae; epipleural edge moderately strong, ending at strongly rounded external apical angle of elytra, epipleura densely setose, apical border narrowly membraneous, with a rim of short microtrichomes.

Ventral surface dull, with coarse and dense punctures, glabrous except minute setae in punctures. Metacoxa only laterally with a few robust longer setae. Abdominal sternites finely and densely punctate and minutely setose, each sternite with a distinct transverse row of coarse punctures each bearing a short, robust seta. Mesosternum between mesocoxae as wide as mesofemur. Ratio of length of metepisternum/metacoxa: 1/1.43. Pygidium strongly convex and dull, with coarse, dense punctures and a few fine, long setae on posterior half.

Legs moderately slender; femora finely densely and coarsely punctate and glabrous, except for minute setae of punctures, with two longitudinal rows of setae; anterior margin of metafemur acute, with an adjacent continuously serrated line, ventral posterior margin weakly widened in apical half but not serrate, dorsal posterior margin completely smooth as well. Metatibia moderately slender and short, widest at middle, ratio width/length: 1/3.4, sharply carinate dorsally, with the basal group of spines at 3/5 the apical one at 4/5 of metatibial length, basally with a few single spines in punctures; beside dorsal margin with a continuously serrated line until the basal group of spines convergent with dorsal margin, between serrated line and dorsal margin finely punctate; lateral face longitudinally convex, with dense and coarse punctures bearing each a minute seta; ventral margin serrated, with three fine and long, equidistant robust setae; medial face sparsely coarsely punctate, punctures with minute setae; apex interiorly near tarsal articulation shallowly concavely sinuate. Tarsomeres dorsally impunctate, ventrally with short, sparse setae. Metatarsomeres ventrally with a strongly serrated ridge, laterally not carinate; first metatarsomere distinctly shorter than following two tarsomeres combined and little longer than dorsal tibial spur. Protibia moderately long, bidentate, protarsal claws symmetrical, basal tooth of inner claw simply but sharply truncate at apex.

Aedeagus: Fig. 1A–C . Habitus: Fig. 1D .

Figures

FIGURE 1. A–D: Amiserica rufidula Nomura, 1974 (Taiwan: Tao Yuan Co.); E–H: A. sacculiforceps Ahrens, Fabrizi & Liu, new species (holotype); I–M: A. zhongtiaoshanensis Ahrens, Fabrizi & Liu, new species (holotype). A, E, I: Aedeagus, left side lateral view; C, G, L: Aedeagus, right side lateral view; B, F, J: Parameres, dorsal view; K: Aedeagus, dorsal view; D, H, M: Habitus (not to scale). Scale: 0.5 mm.

FIGURE 15. Distribution of the species of the Amiserica rufidula group, part 3.