Indomias prasinus (Boheman)

Y, R A M A M U Rt H & Ayri, Shaloo, 2010, Revision of the genus Indomias Marshall (Coleoptera, Curculionidae, Entiminae, Tanymecini) from India, Zootaxa 2357, pp. 1-49 : 41-42

20. Indomias prasinus (Boheman)

(figs. 12, 40, 62, 100, 173, 213, 214 and 215)

Brachyaspistes prasinus Boheman, 1845: 416

Sympiezomias prasinus (Boheman) Marshall, 1916: 162 ; 1941: 350 [NRS] prasinus var. subcostatus ( Marshall)

Description: Colour black, with uniform, dense green or blue green vestiture, sometimes with finely interspersed dark scales; sides and posterior margin of prothorax, and inflexed margins of the elytra with more or less distinct sulphur yellow powdering, vestiture not or but very slightly metallic. Head as long as rostrum, upper surface convex, with scattered punctations, hidden behind dense vestiture. Rostrum deeply impressed at middle dorsally; 1.1x as broad as long, anterior margin only 0.65x broad as the posterior margin; median furrow very short, broad, forked posteriorly; lateral carinae running through length of rostrum; scrobes narrow and sharply pointed at either ends, much broader and parallel in between. Eyes dorsal, moderately convex, 1.7x as long as broad (figs. 12 and 40). Antennae brown; scape gradually broadened; funicle with first segment 0.85x as long as second, but broader than second, other funicular segments elongate, bead shaped; club with fourth joint invisible and bulbous (fig. 62). Prothorax 1.08x as broad as long, its breadth at middle 1.04x as its breadth at posterior margin; sides rounded anteriorly, but straight posteriorly; anterior margin 0.76x as broad as posterior margin, truncate dorsally and vertical laterally, posterior margin subtruncate; upper surface with shallow, confluent punctations, intervals coriaceous or obscurely granulate; median stria faint, broken but distinct posteriorly; laterally with two, distinct pits, due to impressions near the posterior margin. Legs with hind tibial apex without any dense, golden yellow hairs. Elytra narrowly ovate (male) or broader (female), with basal margin only slightly raised; its extenal angle obtuse, with distinct prominent humeral fold; apices with distinct sharp mucros in both sexes; striae finely punctate, with a shallow impression on declivity; intervals broad, almost plain, and of even height, third distinctly raised over second, at posterior declivity near apex, elongate scales inconspicuous, declivity not impressed; elytral vestiture with predominant scales obovate, orange red with 10–11 broken ridges and pedicel (fig. 100).

Male genitalia: Aedeagus with median lobe in profile arcuate at base, apex rounded, length: breadth ratio 7.5:1, broadest at junction with apophyses; transfer apparatus with a sclerotized pouch at the middle; apophyses slender, 0.66x as long as the median lobe (figs. 213–214). Tegmen with dorsal piece 3x as broad as the basal piece, very long, 0.2x as long as manubrium; parameres moderately long, slender, their apices indistinct; manubrium 0.66x as long as median lobe, uniformly thick and with a pointed apex (fig. 215). Spiculum gastrale with shaft 2x as long as manubrium, uniformly thick throughout except at apex, which is slightly narrow, deflected and rounded; basal prongs equal, their apices pointed (fig. 173).

Length: male, 7.1 mm; Breadth: male, 2.65 mm.

Specimens examined: 1 male, INDIA: Tamil Nadu: Nilgiris, Coonoor, 6–13.V.1919, Coll. P. S. Nathan (NPC).

Distribution: India: Tamil Nadu: Nilgirii Hills.

Taxonomic note: Marshall (1916) described an infraspecific taxa namely, variety subcostatus; except for some minor morphological differences, Marshall confirms that it is indistinguishable based on male genitalia. Furthermore, as the species I. prasinus and its variety subcostatus are not geographically isolated it is not considered as a subspecies in the present study.