Holopsis ryukyuensis, Furukawa, 2012

Furukawa, Kota, 2012, A Revision of the Genus Holopsis Broun (Insecta: Coleoptera: Corylophidae) from Japan, Species Diversity 17 (2), pp. 177-186 : 185-186

Holopsis ryukyuensis sp. n.

( Figs 1F , 7A–F )

Type material. Holotype: female. “[Okinawa: JAPAN]/ Mt. Komi-dake /Iriomote-jima I./3.XII.2009/K. FURUKAWA leg.// Holopsis ryukyuensis /FURUKAWA, 2012/Det. K. FURUKAWA, 2012” ( SEHU) . Paratypes: 1 male. “ Otomirindou / Iriomote-jima / Ryukyus / 13-III-1999 / T. Mizoguchi // Holopsis ryukyuensis /FURUKAWA, 2012/det. K. FURUKAWA, 2012” ( EUMJ); 1 male . “[RYÛKYÛ Japan ]/ Mt. Omoto Ishigaki-shi /(Altitude: 400–520)/ 8. V. 2003 [Ishigaki-jima (Japanese)]/ T. Kurihara leg.// Holopsis ryukyuensis /FURUKAWA, 2012/Det. K. FURUKAWA, 2012” ( EUMJ) .

Diagnosis. Although this species is very similar to the other species of Holopsis in Japan in its external morphology, it has sparser punctures of the pronotum and elytra than the others and does not have wavy lines on the metaventrite.

Its penis has a rather short sclerite that is broader than those of H. kirejtshuki and H. punctipennis . This together with the spermatheca with its bent sperm duct lobe and very long and slender gland duct lobe is very reliable characters to identify this species.

Description. Length 1.01–1.38 mm; width 0.84– 1.03 mm. Dorsal surface almost entirely dark brown, but usually paler near elytral suture; anterior margin of pronotum yellow, turning transparent towards edges; ventral surface brown to dark brown with pale brown hypomeron; mouth parts and legs pale brown; antennae pale brown with 3 apical segments slightly darker ( Fig. 1F ).

Body nearly circular, strongly convex, 1.3–1.4 times as long as wide; pronotum 0.4 times as long as wide; elytra 1.0× as long as wide, 2.8–3.1 times as long as pronotum, 1.2 times as wide as pronotum. Antennomere 3 very elongate; antennomeres 4, 6, 7, and 8 transverse; antennomere 5 nearly square; antennomere 11 apically pointed. Labrum rectangular and slightly emarginate medially, with rounded apical angles. Labium rectangular with pentagonal ridge. Pronotum with entirely rounded anterior margin; punctures somewhat sparse and fine in very shallow depressions, with fine and short pubescence; interspaces smooth and shining ( Fig. 7A ). Scutellum transverse with slightly rounded sides ( Fig. 7A ). Elytra widest about 1/3 of way from base; punctures somewhat sparse in shallow depressions, with fine and short pubescence; interspaces smooth and shining; sutural striae absent ( Fig. 7A ). Metaventrite about 0.5 times as long as wide; metaventrite of male with longitudinally oval median depression; punctures fine and dense medially, sparse laterally, with fine pubescence; interspaces without distinct lines ( Fig. 7B ). Wings functional.

Penis as shown in Fig. 7C–D : in ventral view broad, but tapering near pointed apex; in lateral view arched evenly, with pointed apex; internal armature with symmetrical forked sclerite and winding tube. Tegmen as shown in Fig. 7E : phallobase triangular with rounded apex.

Bursa copulatrix ( Fig. 7F ) without apical spines. Spermathecal duct ( Fig. 7F ) thicker in basal part, entering at apex of sperm duct lobe. Spermatheca as shown in Fig. 7F : habitus entirely winding; body slightly swollen and fused with gland duct lobe, with membranous patch; gland duct lobe very long, and slender, winding for whole length; sperm duct lobe bent, with inner and middle parts annulate; gland duct entering outer side of body of spermatheca.

Etymology. The specific name of this species refers to the Ryukyu Islands, which include the type locality, Iriomote Island.

Distribution. Japan: Ryukyu Islands (Iriomote Island, Ishigaki Island).

Figures

Fig. 1. Habitus of Holopsis spp. A, B, H. punctipennis Matthews, male; C, H. kirejtschuki Bowestead, male; D, H. kurilensis Bowestead, male; E, H. lewisei Matthews, male; F, H. ryukyuensis sp. n., male: A, C, D, E, F, dorsal view; B, lateral view.

Fig. 7. H. ryukyuensis sp. n. A, near scutellum, dorsal view (SEM photograph); B, metaventrite of male, ventral view; C, penis, ventral view; D, ditto, lateral view; E, tegmen, dorsal view; F, bursa copulatrix, spermathecal duct, and spermatheca, dorsal view.