Hyposerica courtoisi, Ahrens, Dirk & Fabrizi, Silvia, 2009

Ahrens, Dirk & Fabrizi, Silvia, 2009, A new species of Hyposerica Brenske, 1897 (Coleoptera: Scarabaeidae: Sericini) from Mauritius Island, Zootaxa 2208, pp. 65-68 : 65-67

Hyposerica courtoisi sp. n.

Fig. 1

Type material examined. Holotype: 3 " Mauritius Macabé Forest 12.2.[19]63 C.M. Courtois" ( SANC). Paratypes (3): " Mauritius Macabé 12.i.1970 C.M. Courtois" (13, 1Ƥ SANC, 13 BMNH).

Holotype description. Length: 15.2 mm, length of elytra: 12 mm, width: 7.5 mm. Body oval, dark reddish brown, shiny; dorsum glabrous, except for a few small setae on the head and elytra; wings fully developed as in all other known Hyposerica species.

Labroclypeus subtrapezoidal, distinctly wider than long, widest at base; lateral margins weakly convex and strongly convergent to strongly rounded anterior angles; lateral border and ocular canthus producing an indistinct blunt angle; margins moderately reflexed, anteriorly shallowly sinuate medially; surface weakly convex medially, shiny, very densely punctate, distance between punctures irregular sometimes less than their diameter, with a few long, erect setae behind anterior margin. Frontoclypeal suture feebly impressed and weakly curved medially; smooth area in front of eye approximately twice as wide as long; ocular canthus short and moderately broad, finely and densely punctate, without terminal setae. Frons shiny; with fine, very dense punctures on anterior half, almost smooth on posterior half; completely glabrous. Eyes moderately large, ratio of diameter / interocular width: 0.7. Antenna yellowish brown, composed of ten antennomeres; club with three antennomeres, as long as remaining antennomeres combined. Mentum anteriorly elevated and flattened.

Pronotum widest at base; lateral margins straight, weakly narrowed to the middle, in anterior half strongly convex and convergent anteriorly; anterior angles distinctly produced and sharp; anterior marginal line complete and convexly produced medially; surface densely and finely punctate, most punctures contiguous; disc glabrous, anterior and lateral borders setose; base of pronotum without marginal line; hypomeron ventrally produced and carinate at base. Scutellum broad, triangular, with fine and very dense punctures, with a slightly elevated impunctate area along the middle.

Elytra oblong, widest at posterior third; striae distinctly impressed, finely and densely punctate; intervals almost flat, odd intervals half as wide as even ones with fine, dense punctures; glabrous except a few fine, erect, short setae on apex and lateral intervals. Epipleural edge robust, ending at the weakly convex external apical angle of elytra; epipleura moderately setose, apical border without a rim of short microtrichomes.

Ventral surface shiny; thorax and metacoxa with large and dense punctures, densely setose; metacoxa glabrous except for numerous long setae laterally and anteriorly, posteriorly without marginal line or membranous rim. Mesosternum between mesocoxae as wide as mesofemur. Ratio of length of metepisternum / metacoxa: 1 / 1.34. Each abdominal sternite, in addition to generally distributed fine and moderately dense punctures, with a distinct transverse row of coarse punctures each bearing a long and robust seta; ultimate sternite along the entire basal margin with a distinct marginal fold. Pygidium weakly convex, finely and densely punctate, without smooth midline, punctures with numerous long setae apically.

Legs moderately broad and shiny; femora with two longitudinal rows of setae, finely and sparsely punctate; metafemur with anterior edge acute, lacking an adjacent serrate line, posterior ventral margin medially slightly convexly curved, convergent with anterior margin in apical third and not serrate; dorsally not serrate, finely setose. Metatibia moderately broad and long ( Fig. 1 D), widest at apex, ratio width / length: 1 / 3.0; dorsally longitudinally convex, with three groups of spines, basal one at first quarter, median one at one-third, and apical one at second third of metatibial length; basally with a few punctures, each bearing short single setae; lateral face longitudinally convex, with moderately dense and fine punctures, glabrous, apically punctures more sparse; ventral edge moderately sharp and only slightly serrate, with 5 fine spines equidistant from each other, medial face not punctate; apex interiorly near tarsal articulation deeply concavely sinuate at middle; serrate line from ventral margin extending onto the dorsal portion of sinuation. Tarsomeres dorsally smooth, ventrally with sparse, short setae; metatarsomeres ventrally glabrous, with a strongly serrate ridge, beside which is a strong longitudinal carina; first metatarsomere as long as the following tarsomere but a little longer than the upper tibial spur. Protibia short, tridentate, basal tooth small, external basal margin completely smooth. All claws symmetrical, feebly curved and long, with normally developed basal tooth.

Aedeagus: Fig. 1 E–G.

Variation. Length: 15.2–16.3 mm, length of elytra: 11.3–12 mm, width: 7.0– 7.5 mm. Female: eyes slightly smaller (ratio diameter / interocular width: 0.6) (antennal club lacking in female paratype).

Diagnosis. Hyposerica courtoisi is most similar to H. vinsoni Arrow, 1948 in external appearance and shape of the male genitalia. It may be differentiated from the latter by larger body size and the general shape of parameres: in the new species the right paramere is significantly shorter than the left and has a large, basal lobe interiorly while the left paramere has a strong, lateral tooth apically ( Fig. 1 E–G).

Etymology. The new species is dedicated to its collector, C. M. Courtois.

Figures

FIGURE 1. Hyposerica courtoisi sp. n. (A – D: paratype; E – G: holotype). A: habitus, dorsal view; B: habitus, lateral view; C: head and pronotum, perpendicular dorsal view; D: metatibia (lateral view); E: aedeagus, left side lateral view; F: parameres, perpendicular dorsal view; G: aedeagus, right side lateral view. A – D: not to scale, E – G: scale 1 mm.