Gynaecoserica krausi Ahrens, 2022

Ahrens, Dirk, 2022, New Gynaecoserica Brenske, 1897 species and further new bicolored species of the Neoserica calva group (Coleoptera: Scarabaeidae: Melolonthinae: Sericini), Zootaxa 5165 (2), pp. 180-190 : 182-184

Gynaecoserica krausi Ahrens , new species

Fig. 1F–I

Type material. Holotype: ♂ “ LAOS, Xieng Khouang prov., 19°37–8'N, 103°20'E, Phonsavan (30 km NE) Phou Sane Mt. , 1420 m, 10-30.v.2009, Z. Kraus leg. / NHMB Basel, NMPC Prague, Laos 2009, Expedition: M. Brancucci, M. Geiser, Z. Kraus, D. Hauck, V. Kubáň / 1095 Sericini Asia spec.” ( NHMB) . Paratype: 1 ♂ “ LAOS, Xieng Khouang prov., 19°37–8'N, 103°20'E, Phonsavan (30 km NE) Phou Sane Mt. , 1420 m, 10-30.v.2009, Z. Kraus leg. / NHMB Basel, NMPC Prague, Laos 2009, Expedition: M. Brancucci, M. Geiser, Z. Kraus, D. Hauck, V. Kubáň ” ( ZFMK) .

Description of the holotype. Length: 4.0 mm, length of elytra: 2.2 mm, width: 2.1 mm. Body oblong, dorsal surface yellowish brown, antennal club, head, margins of elytra, and anterior half of pronotum dark brown, antennal funiculus and legs yellow, except shiny head dorsal surface dull, sparsely setose.

Labroclypeus widest at base, lateral margins in basal half subparallel, anteriorly strongly convex, anterior angles strongly convex, lateral border and ocular canthus producing a distinct blunt angle; margins weakly reflexed; anterior margin very shallowly sinuate medially; surface weakly elevated medially and weakly shiny, finely and coarsely but densely punctate, distance between punctures less than their diameter, behind anterior margin with a few long, erect setae; frontoclypeal suture feebly incised and curved; smooth area in front of eye almost as wide as long; ocular canthus short and slender (length subequal 1/3 of ocular diameter), finely densely punctate, with a short terminal seta. Frons weakly shiny, posterior quarter dull, with fine and coarse, moderately dense punctures, with some long erect setae beside eyes, otherwise punctures with minute setae. Eyes very small, ratio of diameter/interocular width: 0.42. Antenna yellow, with ten antennomeres; club dark brown, with seven antennomeres, slightly reflexed, 1.2 times as long as the remaining antennomeres combined. Mentum weakly elevated and flattened anteriorly.

Pronotum moderately wide, widest at base, lateral margins subparallel and straight in basal half, in anterior half weakly curved and convergent anteriorly, anterior angles moderately produced and sharp, posterior angles blunt; anterior margin convexly produced medially, with a distinct fine marginal line, basal margin without marginal line; anterior and lateral finely sparsely setose; surface with moderately dense and fine punctures, with microscopic white setae in punctures, otherwise glabrous; hypomeron distinctly carinate at base but not ventrally produced. Scutellum dark brown, narrow and moderately short, triangular, with dense, large but shallow punctures, punctures with microscopic setae.

Elytra moderately long, widest at middle, striae weakly impressed, finely and densely punctate; intervals weakly convex, with fine and moderately dense punctures concentrated along striae, punctures with minute white adjacent setae, odd intervals with a few single robust, yellow, erect setae; interior apical angle of elytra with a strong seta; epipleural edge fine ending at strongly curved external apical angle of elytra; epipleura sparsely setose, apical border without short microtrichomes (visible at 100x magnification).

Ventral surface dull, with fine and moderately dense punctures, sparsely setose; metacoxa only laterally with a few strong adjacent setae. Each abdominal sternite with indistinct transverse row of coarse punctures bearing short setae between fine, dense punctation. Mesosternum between mesocoxae as wide as mesofemur, with irregularly scattered very strong setae. Ratio of length of metepisternum/metacoxa: 1/1.52. Pygidium strongly convex, coarsely and densely punctate, without smooth midline, partly shiny, with short dense setae at apex, a few long setae beside apical margin.

Legs moderately slender and long; femora dull, with two longitudinal rows of setae, finely and sparsely punctate; metafemur shiny, sharply carinate anteriorly and without a submarginal serrate line; ventral posterior margin weakly convex and glabrous, only weakly widened in apical half and not serrate, dorsally posterior margin finely serrate, with short setae. Metatibia slender and moderately long, widest at middle of metatibial length, ratio width/ length: 1/3.45, dorsally moderately carinate, with two groups of spines, basal one at anterior quarter, apical one at two thirds of metatibial length, basally nearly glabrous; lateral face longitudinally convex, with sparse and fine punctures, glabrous; ventral margin carinate and serrate, with three strong spines, of which the two distal are widely separated; internal face very finely and sparsely punctate; apex interiorly near tarsal articulation sharply and deeply truncate. Tarsomeres dorsally glabrous and impunctate, ventrally with sparse, short setae; metatarsomeres ventrally with a strongly serrate ridge, beside which is a fine longitudinal carina; first metatarsomere as long as following two tarsomeres combined and twice as long as dorsal tibial spur. Protibia moderately long, bidentate, protarsal claws symmetrical.

Aedeagus: Fig. 1F–H . Habitus: Fig. 1I .

Female unknown.

Diagnosis. Gynaecoserica krausi Ahrens , new species differs from all other so far known Gynaecoserica species by the antennal club composed of seven antennomeres, and in addition by the dorsally strongly arched phallobase, which has on each side of the apex a lateral apophysis.

Variation. Length: 4.0– 4.2 mm, length of elytra: 2.2–2.3 mm, width: 2.1–2.2 mm. Dark dorsal portions in the paratype with some greenish shine, dark margins of elytra less distinct.

Etymology. The new species is named after its collector, Zdeněk Kraus.

Figures

FIGURE 1. A–E: Gynaecoserica obfuscata Ahrens, new species (holotype); F–I: G. krausi Ahrens, new species (holotype). A, F: Aedeagus, left side lateral view; D, H: Aedeagus, right side lateral view; B, G: Parameres, dorsal view; C: Aedeagus, dorsal view; E, I: Habitus (not to scale). Scale: 0.5 mm.