Miridiba vethi ( Moser, 1917 )

Gao, Chuan-bu & Coca-Abia, María Milagro, 2021, Revision of the genus Miridiba Reitter, 1902 (Coleoptera, Scarabaeidae, Melolonthinae): genital morphotypes and new taxonomic data, European Journal of Taxonomy 749, pp. 1-94 : 60-62

Miridiba vethi ( Moser, 1917)

Figs 77–78

Holotrichia vethi Moser, 1917: 90 (type loc.: Batoe Bara, Sumatra).

Miridiba vethi – Matsumoto 2017: 1, figs 1–6 (combination).

Diagnosis

External morphology of adult ( Fig. 77 ). Dorsal surface glabrous.Clypeus concave, shorter than frons, oblique laterally, anterior edge strongly emarginate at middle. Frons with sharp carina. Anterior pronotal margin glabrous, strongly flanged, narrowed at middle and at lateral ends; posterior margin glabrous, moderately flanged; lateral margins smooth, glabrous, moderately elevated at anterior half; anterior angles almost right and rounded, not projected forward; posterior angles obtuse and rounded. Pronotal surface densely punctate, each puncture with a tiny bulge hardly visible. Scutellum sparsely punctate. Elytral surface with punctures regularly distributed; each puncture with a tiny bulge hardly visible; apical callus well defined; epipleuron glabrous with membrane. Foretibia with a moderately developed dorsal carina; insertion of inner spur closer to third outer tooth than second one. Meso- and metatibia with transverse carina interrupted and complete respectively; inner margin of dorsal surface with few spines. Pygidium irregularly punctate; punctures thinner at anterior margin; surface without conspicuous pubescence, at most with tiny setae in each puncture hardly visible, apical margin with long pubescence. Ventrites 2, 3 and 4 without conspicuous pubescence, with small scales hardly visible. Ventrite 5 moderately depressed at posterior half with punctures uniformly distributed and long pubescence irregularly distributed on posterior half; anterior half without conspicuous pubescence. Ventrite 6 moderately bulging anteriorly; conspicuous pubescence irregularly distributed. Male genitalia ( Fig. 78 ): dorsal branch of parameres thin and symmetrical, with sutural scar completely fused, triangular at proximal end, tapered with a rounded tip curving downward at distal end. Ventral branches with elevations as waves at outer margin, apices upward. Endophallus and temones not studied. Female genitalia: median oviduct with wrinkled and hardened epithelium; elongate plates of gonopore fold with sensillae; conspicuous vestigial sternites placed ventrally at gonopore.

Material examined

Lectotype (here designated) SUMATRA • ♂; “ Sumatra on Batoe Bara ”; “ Holotrichia vethi Mos Type ♂”; “Syntypus Holotrichia vethi Moser, 1917 labelled by MNHUB 2016 ”; “Lectotype Miridiba vethi ( Moser, 1917) Chuan-bu Gao & Coca-Abia det. 2019”; MFNB.

Paralectotypes (here indicated) SUMATRA • 1 ♂ (without head and pronotum); “Sumatra on Batoe Bara”; “Syntypus Holotrichia vethi Moser, 1917 labelled by MNHUB 2016 ”; “Paralectotype Miridiba vethi ( Moser, 1917) Chuan-bu Gao & Coca-Abia det. 2019”; MFNB • 1 ♀; “Coll Nonfried Sumatra ”; “ Holotrichia vethi Mos Type ♀”; “Syntypus Holotrichia vethi Moser, 1917 labelled by MNHUB 2016 ”; “ Chuan-bu Gao & Coca-Abia det. 2019”; MFNB.

Remarks

Moser (1917) described Holotrichia vethi from Sumatra (Batoe Bara). Matsumoto (2017) transferred this species to Miridiba after studying three syntypes (two males and one female), and no lectotype was designated. After studying these three syntypes (MFNB), we agree with the transfer of H. vethi to Miridiba and designate the lectotype and two paralectotypes. Moreover, we confirm the similarities of M. vethi with M. laosana , M. bidentata , M. malaccensis and M. waterstradti ( Matsumoto 2017) . Just like the four species, M. vethi shows features that characterize morphotype IV “ Bilobata ”. Hence, we consider it to belong to this genital morphotype.

Distribution

Indonesia (Sumatra).

Figures

Figs 77–78. Miridiba vethi (Moser, 1917), lectotype, ♂ (MFNB). 77. Habitus in dorsal view. 78. Parameres in dorsal (A) and lateral (B) views. Scale bars: 77 = 5.0 mm; 78 = 1.0 mm.