OCR Text |
Show 1892.] PHYTOPHAGOUS COLEOPTERA FROM MADAGASCAR. 575 the latter strongly rounded at the middle, the posterior angles produced into an acute tooth, the surface rather convex, transversely depressed at the base, entirely impunctate ; elytra strongly narrowed posteriorly, fulvous, shining, impunctate, or exceedingly finely and sparingly punctured, the interstices very finely wrinkled here and there. The shape of the thorax is peculiar in this species, and the posterior angles are distinctly dentate, the tooth being placed above the middle line of the posterior margin, the angles themselves being obliquely shaped. MALACOSOMA SIKOR^E, n. sp. Piceous ; the antennae and the labrum fulvous ; thorax finely punctured ; elytra more closely punctate, the punctures arranged in closely approached rows. Length 2-2| lines. Head impunctate, the frontal tubercles transversely oblique, the clypeus strongly triangularly raised ; labrum pale fulvous ; palpi slender, piceous ; antennae extending to half the length of the elytra, pale fulvous, the joints very slender, the third and fourth equal; thorax subquadrate, about one half broader than long, the sides nearly straight or slightly angulate before the middle ( 2 ?)> the anterior angles distinct, furnished with a single hair, the surface distinctly but not very closely punctured, piceous ; elytra with a very slight depression below the base, closely and scarcely more strongly punctured than the thorax, the punctures arranged in closely approached semi-regular rows ; legs more or less fulvous; tibiae mucronate, the first joint of the posterior tarsi as long as the three following j"ints together ; prosternum narrowly raised. The two specimens before me show some differences which are probably sexual : in one the thorax is less transverse, with nearly straight lateral margins, and the elytra have a slight purplish gloss and are more irregularly punctured; in the other specimen the thorax is broader and the sides are distinctly subangulate before the middle, the elytra have no metallic gloss and are more regularly and less closely punctured in rows; both specimens, however, apparently represent the same species ; the last abdominal segment in both is simple. MALACOSOMA ATERRIMUM, n. sp. Entirely black; the thorax but slightly broader than long, impunctate ; elytra entirely impunctate. Length 2 lines. Head impunctate, black, the frontal tubercles distinct, transverse ; palpi slender, the terminal joint acutely pointed ; the antennae extending to half the length of the elytra, black, the third joint slightly longer than the second ; thorax subquadrate, about one half broader than long, the sides very slightly rounded, the anterior angles rather prominent, the surface entirely impunctate; elytra without basal depression, rather opaque, impunctate ; tibiae armed with a small spine, the first joint of the posterior tarsi as long as the three 39* |