OCR Text |
Show 1899.] PHYTOPHAGOUS COLEOPTERA O F AFRICA. 367 HEMIXANTHA, gen. n. Body elongate and parallel; antennas filiform, the third joint slightly longer than the second, but shorter thau the fourth ; thorax transverse without depressions, the sides rounded ; elytra not narroAver than the thorax, irregularly punctured and rugose, their epipleuras broad anteriorly, indistinct below the middle; legs slender, the tibiae unarmed, the first tarsal joint of the posterior legs as long as the following three joints together, claws appendi-culate, the prosternum indistinct; the anterior coxal cavities closed. This genus will enter the group of Platyxanthince on account of the unarmed tibias and closed coxal cavities, but it must be separated from Platyxantha on account of the differently shaped and structured thorax ; the latter genus contains already far too many species of different kind of structural characters than the type, and Avants revision. Metrioidea Fairm. has a subquadrate thorax, narroAver than the elytra, and the same is the case in Platyxantha proper, in which the thorax is also more or less depressed or sulcate and not transverse. In Hemixantha must also be arranged the folloAving species formerly placed by m e in Platyxantha :-H. pallida Jac, H. scutellata Jac, which, although not metallic in coloration, exhibit the same structural characters. HEMIXANTHA NATALENSIS, sp. n. (Blate XXI. fig. 8.) Bluish or greenish black below, above metallic green or blue, the antennas and tarsi black; thorax closely punctured and rugose ; elytra as closely punctured and finely transversely wrinkled throughout. Length 4 millim. Head finely punctured at the vertex, the frontal tubercles very broad, subquadrate, aud strongly raised ; clypeus in shape of a transverse acute ridge ; labrum black ; antennas extending beyond the middle of the elytra, slender, black, the loAver three or four joints more or less fulvous below, the basal joint metallic dark green or bluish above ; thorax twice as broad as long, transversely convex, the sides rather strongly rouuded and widened at the middle, the angles distinct, the surface very closely and distinctly punctured, the interstices irregularly rugose or wrinkled; scutellum rather broader than long, impunctate ; elytra parallel, scarcely narroAver at the base than tbe thorax, the surface nearly similarly sculptured to that of the thorax, but the interstices more finely transversely Avrinkled and minutely granulate; underside black, with a slight bluish or greenish gloss, the legs more distinctly of the latter tint, finelv pubescent. Hab. Frere, Natal (G. Marshall). In the male insect the last abdomiual segment is semicircularly emarginate at the apex, and the protruding penis is slender and pointed and slightly curved at the apex. |