Amiserica strnadi Ahrens, Fabrizi & Liu, 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 : 25-26

Amiserica strnadi Ahrens, Fabrizi & Liu , new species

Figures 6E–H , 15

Type material examined. Holotype: ♂ “ Vietnam N 1990 Sa-Pa 11–19.VI. 1600 m Hoang Lien Son prov. Strnad Jan lgt / Sericini Asia spec. 439” ( ZFMK). Paratype: 1 ♂ “ Vietnam N (Sa Pa) Lao Cai Prov., 250 km from Hanoi bearing 31°, Sa Pa vill. env. Hoang Lien Son Nat. Res. 16.– 20.6.1998 1250 m leg. A. Napolov ” ( CNA).

Description of the holotype. Length: 5.2 mm, length of elytra: 3.8 mm, width: 3.2 mm. Body oval, reddish brown, surface dull, labroclypeus shiny, antenna yellowish brown, dorsal surface almost glabrous.

Labroclypeus narrowly 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, finely and densely punctate, with sparse 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, shiny in anterior quarter, finely and moderately densely punctate, with sparse long setae behind frontoclypeal suture. Eyes moderately large, ratio of diameter/interocular width: 0.62. Antenna with ten antennomeres, club with four antennomeres, slightly reflexed externally, 2.7 times as long as remaining antennomeres combined. Mentum elevated and flattened anteriorly.

Pronotum widest at base, lateral margins in basal half straight and subparallel, in anterior part strongly curved and convergent to moderately produced and moderately sharp anterior angles, posterior angles nearly rectangular; anterior margin distinctly convex, with the marginal line widely 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, punctures with minute setae only.

Elytra oval, widest at middle, striae distinctly impressed, with fine and dense punctures; intervals moderately convex, with fine, evenly 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 membraneous, with a fine rim of 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: 1/1.57. Pygidium moderately convex and dull, with fine, dense punctures and a few fine, short setae along the apical margin.

Legs moderately wide; 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 moderately widened in apical half and not serrate, dorsal posterior margin completely smooth as well. Metatibia wide and moderately long, widest at middle, ratio width/length: 1/3.3, sharply carinate dorsally, the basal group of spines shortly behind the middle, the apical one at ca 4/5 of metatibial length, basally with a few single robust spines in punctures; beside dorsal margin with a continuously serrated line until the distal group of spines being convergent with dorsal margin at apex, between serrated line and dorsal finely sparsely punctate; lateral face flat, with moderately dense and coarse punctures bearing each a short seta; ventral margin serrated, with three 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 as long as following two tarsomeres combined and a quarter of its length longer then dorsal tibial spur. Protibia moderately long, bidentate, protarsal claws symmetrical, basal tooth of inner claw simply but sharply truncate at apex.

Aedeagus: Fig. 6E–G . Habitus: Fig. 6H . Female unknown.

Variation. Length: 5.2–5.3 mm, length of elytra: 3.8–3.9 mm, width: 3.2–3.3 mm.

Diagnosis. Amiserica strnadi Ahrens, Fabrizi & Liu , new species differs from A. antennalis by the parameres being at apex strongly curved dorsally, the lateral lobe of left paramere being distinctly divergent from the paramere.

Etymology. The new species is named after its collector, Jan Strnad.

Figures

FIGURE 6. A–D: Amiserica basisymmetrica Ahrens, Fabrizi & Liu, new species (holotype); E–H: A. strnadi 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 15. Distribution of the species of the Amiserica rufidula group, part 3.