Neoserica ihlei Ahrens & Pham, 2021

Ahrens, Dirk & Pham, Phu Van, 2021, Additions to the Neoserica calva group from continental South East Asia (Coleoptera: Scarabaeidae: Melolonthinae: Sericini), Zootaxa 5032 (3), pp. 357-378 : 371-373

Neoserica ihlei Ahrens & Pham , new species

Fig. 4F–J

Type material. Holotype: ♂ “ THAILAND, N: Chang Mai Prov. Doi Pha Hom Pok, 23.-29.I.2004 leg. T. Ihle ” ( ZFMK) . Paratypes: 9 ♂♂, 9 ♀♀ “ THAILAND, N: Chang Mai Prov. Doi Pha Hom Pok, 23.-29.I.2004 leg. T. Ihle ” ( ZFMK) , 1 ♂, 4 ♀♀ “ THAILAND, N: Chang Mai Prov. Doi Pha Hom Pok, 14.-23.III.2004 leg. T. Ihle ” ( ZFMK) .

Description of the holotype. Length: 5.8 mm; elytral length: 4.5 mm; width: 3.6 mm. Body oblong, reddish brown, frons, pronotum and elytra with numerous, more or less extended darker spots, antennal club yellowish brown, dorsal surface dull and except frons nearly glabrous, labroclypeus shiny.

Labroclypeus subtrapezoidal, little wider than long; lateral margins strongly convex; anterior angles moderately rounded; anterior margin weakly emarginate medially; margins moderately reflexed; surface weakly elevated medially and shiny, finely and coarsely, densely punctate, with numerous erect setae. Frontoclypeal suture finely incised, weakly elevated and curved. Smooth area anterior to eye weakly convex, 1.5 times as wide as long. Ocular canthus moderately long and narrow (equal to 1/3 of ocular diameter), finely and densely punctate, with a single terminal seta. Frons dull, finely and moderately densely punctate, with minute setae in punctures and long setae beside eyes and behind frontoclypeal suture, on posterior half punctures less dense. Eyes large, ratio diameter/interocular width: 0.93. Antenna with ten antennomeres, club with four antennomeres and reflexed, 1.6 times as long as remaining antennomeres combined. Mentum elevated and slightly flattened anteriorly. Labrum transverse, short, not produced medially, with weak median sinuation.

Pronotum transverse, widest at base; in basal half lateral margins moderately convex and convergent anteriorly, in anterior half margins strongly convex and convergent; anterior angles moderately produced and rectangular; posterior angles moderately rounded; anterior margin convexly produced medially, with a fine marginal line; surface moderately densely and coarsely punctate, with minute setae in punctures; lateral and anterior border sparsely setose; basal margin without marginal line; hypomeron distinctly carinate basally. Scutellum short, with fine, very dense punctures and minute setae in punctures.

Elytra oblong, widest at posterior third; striae weakly impressed, finely and moderately densely punctate; intervals flat, with sparse, fine punctures, with minute setae in punctures, odd intervals with a few short single setae, penultimate lateral interval with a few single long setae. Epipleural edge fine, ending at moderately curved external apical angle of elytra; epipleura densely setose; apical border with a fine rim of microtrichomes (visible at 100x magnification).

Ventral surface dull, finely and densely punctate. Metasternum except long setae on disc nearly glabrous, sparsely covered with minute setae in punctures. Metacoxa glabrous, with a few single setae laterally. Abdominal sternites finely and densely punctuate, glabrous except minute setae in punctures, with a transverse row of coarse punctures each bearing a robust long seta. Mesosternum between mesocoxae as wide as mesofemur. Ratio of length of metepisternum/metacoxa: 1/1.53. Pygidium moderately convex and dull, coarsely and densely punctate, with a narrow smooth midline, with a few long setae beside apical margin, otherwise with minute setae only.

Legs moderately slender. Femora with two longitudinal rows of setae, finely and sparsely punctate. Metafemur dull and sparsely finely punctate; anterior margin acute, behind anterior margin without serrated line; posterior margin in apical half serrated ventrally and moderately widened at apex; posterior margin finely serrated dorsally, glabrous. Metatibia slender and short, widest at apex, ratio of width/length: 1/3.7; dorsal margin sharply carinate, with two groups of spines; basal group at middle, apical group at three quarters of metatibial length; in basal half with a few short robust setae in single robust punctures with serrated margin; external face longitudinally convex, finely and sparsely punctate; ventral margin finely serrated, with three robust setae, with the apical one being much more distant; medial face impunctate, glabrous, apex bluntly truncate interiorly near tarsal articulation. Tarsomeres ventrally with sparse, short setae, not carinate laterally, with dense longitudinal punctures dorsally; metatarsomeres laterally carinate; metatarsomere 1 twice as long as dorsal metatibial spur and as long as following two tarsomeres combined. Protibia moderately long, bidentate, bluntly widened laterally before basal tooth; anterior claws symmetrical, basal tooth of inner claw sharply truncate at apex.

Aedeagus: Fig. 4F–I . Habitus: Fig. 4J .

Variation. Length: 5.7–6.4 mm; elytral length: 4.5–4.9 mm; width: 3.5–3.8 mm. Female: eyes as large as in male, antennal club short and composed of three lamellae, little shorter than remaining antennomeres combined; pygidium weakly convex.

Diagnosis. Neoserica ihlei Ahrens & Pham , new species differs from Neoserica peregovitsi Ahrens & Pham , new species and N. ailaoshanica Liu, Fabrizi, Bai, Yang & Ahrens, 2014 by the very large eyes (ratio diameter/ interocular distance> 0.9) and by the shape of the apical dorsomedian process of phallobase, being short and bilobed.

Etymology. The new species is named after one of its collector, T. Ihle (noun in genitive singular case).

Figures

FIGURE 4. A–E: Neoserica peregovitsi Ahrens & Pham, new species (holotype); F–J: N. ihlei Ahrens & Pham, new species (holotype). A, F: Aedeagus, left side lateral view; D, I: Aedeagus, right side lateral view; B, G: Parameres, dorsal view; C, H: Aedeagus, dorsal view; E, J: Habitus (not to scale). Scale: 0.5 mm.