Amiserica incisa 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 : 14-16

Amiserica incisa Ahrens, Fabrizi & Liu , new species

Figures 3A–D , 14

Type material examined. Holotype: ♂ “ China-Shaanxi , SW Tsinling Mts., Taiping vill., 33°33'N, 106°43'E, June 2000, 1500–2000m, Siniaev & Plutenko leg. / 840 Sericini : Asia spec.” ( CP) . Paratypes: 18 ♂♂, 3 ♀♀ “ China-Shaanxi, SW Tsinling Mts., Taiping vill., 33°33'N, 106°43'E, June 2000, 1500–2000m, Siniaev & Plutenko leg.” ( CP, ZFMK) , 1 ♂ “ China – Shaanxi, Daba Shan, Shou Man vill., 32°14'N, 108°34'E, 25.v.–14.vi.2000, 1000m, Siniaev & Plutenko leg.” ( CP) , 5 ♂♂ “ China, Shaanxi, Tsingling Mts., 1600m, Nat. Res. Foping , 33°51'N, 107°57'E, 20.iv.–11.v.1999, V. Siniaev & A. Plutenko lgt.” ( CP) , 23 ♂♂ “ China, Shaanxi, Panda area, Nat. Res. Foping , 1600m, 6–11.iv.1999, 33°45‘N, 107°48‘E, V. Siniaev & A. Plutenko lgt.” ( CP, ZFMK) .

Description of the holotype. Length: 8.1 mm, length of elytra: 5.6 mm, width: 4.4 mm. Body oblong, dirty brown, surface dull, labroclypeus shiny, antenna yellowish brown, dorsal surface almost glabrous.

Labroclypeus moderately wide, subtrapezoidal, widest at base, lateral margins weakly convex and convergent to weakly rounded anterior angles, lateral border and ocular canthus producing a distinct angle; anterior margin weakly emarginate medially, margins weakly reflexed; surface flat and moderately shiny, coarsely and densely punctate, with numerous long erect setae on anterior half; 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 in posterior half, anterior half moderately shiny, finely and densely punctate in anterior two third, with a few long setae beside eyes and behind frontoclypeal suture, punctation on posterior third less dense and glabrous. Eyes large, ratio of diameter/interocular width: 0.79. 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 weakly convergent anteriorly, in anterior part strongly curved and convergent to moderately produced and strongly rounded anterior angles, posterior angles blunt; anterior margin distinctly convex, its marginal line widely lacking; 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 dense punctures, smooth on basal midline, punctures with minute setae only.

Elytra oblong, widest in posterior third, striae distinctly impressed, with fine and dense punctures; intervals moderately convex, with fine, evenly and moderately dense punctures, 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: 1/1.3. Pygidium strongly convex and dull, with coarse, dense punctures and a few fine, long setae on posterior half.

Legs 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: 1/4.0, 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 without a continuously serrated line, only around coarse spine-bearing punctures serrated, beside 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, robust setae of which the distal one is more distant from the others; medial face impunctate and glabrous; apex interiorly near tarsal articulation shallowly concavely sinuate. Tarsomeres dorsally impunctate, ventrally with short, dense setae. Metatarsomeres ventrally with a strongly serrated ridge, laterally not carinate; first metatarsomere little 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. 3A–C . Habitus: Fig. 3D .

Variation. Length: 7.0–9.0 mm, length of elytra: 5.4–6.8 mm, width: 3.8–4.9 mm. Female: Eyes smaller, ratio of diameter/interocular width: 0.5; antennal club with four antennomeres, as long as remaining antennomeres combined; pygidium strongly convex, but apical part weakly convex.

Diagnosis. Amiserica incisa Ahrens, Fabrizi & Liu , new species differs from A. antennalis by the lacking serrated line of metatibia and by shape of aedeagus lacking in the latter the dorsolateral processes of phallobase.

Etymology. The name of the new species is derived from the Latin adjective incisus (incised), with reference to the paired dorsolateral phallobasal process which has between each other a deep incision.

Figures

FIGURE 3. A–D: Amiserica incisa Ahrens, Fabrizi & Liu, new species (holotype); E–H: A. funiushanica 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 14. Distribution of the species of the Amiserica rufidula group, part 2.