Amiserica antennalis ( Nomura, 1974 ) Ahrens & Liu & Pham & Fabrizi, 2021

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 : 11-13

Amiserica antennalis ( Nomura, 1974) , new combination

Figures 2A–D , 13

Lasioserica antennalis Nomura, 1974: 83 ; Ahrens 2002: 54, 2006b: 233, 2007: 17; Ahrens & Bezděk 2016: 289.

Material examined. 1 ♀ “ Taiwan Taichung Hsien, Hsuehshan Chi-Ka 2460 m 6.V.91 A. Smetana (T 67)” ( MHNG) , 1 ex. “ Taiwan, Taichung Prov. Anmashan region , 1650 m 20.VI.1997 B. Herczig & L. Ronkay ” ( HNHM) , 2 ex. “ Taiwan Taichung Hsien, Anmashan 2120 m 1.V.1990 A. Smetana [T36]” ( MHNG) , 1 ex. “ Taiwan Taichung Hsien, Anmashan 2230 m 30.IV.–4.V.90 A. Smetana [T32]” ( MHNG) , 2 ex. “ Taiwan: Meifeng 26.IV.1983 H. Townes 2150 m ” ( HAHC) , 2 ex. “ Taiwan: Meifeng 15., 22.V.1983 H. Townes 2150 m ” ( HAHC) , 4 ex. “ Taiwan: Meifeng 3.V.1983 H. Townes 2150 m ” ( HAHC) , 3 ex. “ Taiwan: Meifeng 10.V.1983 H. Townes 2150 m ” ( HAHC) , 4 ex. “ Taiwan: Meifeng 29.V.1983 H. Townes 2150 m ” ( HAHC) , 5 ex. “ Taiwan, Prov. Tai-Tung , 2 km E of Hsingyang, 2200 m, 11.– 13.03.1996 leg.: Gy. Fábián & L. Németh “ ( HNHM) , 1 ex. „ Taiwan, Nantou county, Hohuachi, between Lishan and Tayuling, at the road No. , 8, 1950 m, / 24°11’N, 121°16’E, at light, 31.III.2000, A. Kun & L. Peregovits “ ( HNHM) . From Ahrens (2002), specimens were re-examined here .

Redescription. Length: 7.2 mm, length of elytra: 5.5 mm, width: 4.1 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 moderately 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 numerous long erect setae; 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 behind frontoclypeal suture. Eyes moderately large, ratio of diameter/interocular width: 0.6. Antenna with ten antennomeres, club with four antennomeres, slightly reflexed externally, 2.5 times 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 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 at posterior quarter, 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: 1/1.44. 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 slender and long, widest at apex, ratio width/length: 1/3.9, sharply carinate dorsally, with the basal group of spines shortly behind the middle, the apical one at 5/6 of metatibial length, basally with a few single spines in punctures; beside dorsal margin with a continuously serrated line until the distal group of spines being curved at level of basal group of spines and being convergent with dorsal margin at apex, between serrated line and dorsal impunctate; lateral face longitudinally convex, with sparse and coarse punctures bearing each a minute seta; ventral margin serrated, with four fine and long, equidistant robust setae; medial face impunctate; 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. 2A–C . Habitus: Fig. 2D .

Remarks. Given on the vast variation of genital and antennal morhology represented in the species examined here, we came to the conclusions, that the doubtful Lasioserica Brenske, 1896 species , Lasioserica antennalis Nomura, 1974 , is in fact supposedly closely related to Amiserica rufidula Nomura, 1974 , in contrast to the other Lasioserica species including its type, Lasioserica nobilis ( Brenske, 1894) (see material examined in Ahrens 2002). Interestingly, the state of a 4-lamellate antennal club is common in more species, that the condition of the type species, A. rufidula , having a 3-lamellate club. Consequently, we consider the former to be a member of Amiserica : Amiserica antennalis ( Nomura, 1974) , new combination.

Figures

FIGURE 2. A–D: Amiserica antennalis (Nomura, 1974) (Taiwan: Tai-Tung Prov., 2 km E of Hsiangyang); E–H: A. pseudoantennalis Ahrens, Fabrizi & Liu, new species (holotype). A, E: Aedeagus, left side lateral view; C, G: Aedeagus, right side lateral view; B, F: Parameres, dorsal view; D, H: Habitus (not to scale). Scale: 0.5 mm.

FIGURE 13. Distribution of the species of the Amiserica rufidula group, part 1.