OCR Text |
Show 1881.] COLEOPTERA F R O M ECUADOR. 265 20. ALURNUS SAUNDERSII, Baly, Cat. Brit. Mus. p. 28. A specimen brought by Mr. Buckley appears to be referable to this species, but has a black spot on the shoulder, which is not mentioned in the description. Hab. Ecuador. 21. ALURNUS MUTABILIS, n. sp. (Plate XXX. fig. 3.) Niger, subopacus, thoracis lateribus ehjtrisque pallide flavis, his plus minusve nigro ornatis. Long. 9-10 lin. Thorax one quarter broader than long, moderately convex, very slightly narrower in front than behind, very gently arcuate at the sides ; not very strongly, but rather thickly and irregularly punctured ; yellow, with the disk and the extremely fine lateral margin black ; there is a sudden constriction in front at the extreme anterior margin ; and there is a small incision at each posterior angle. Scutellum smooth, impressed. Elytra dull, pale yellow, parallel at the sides, arcuately acuminate at the apex; very thickly but obscurely punctured; the extreme apical margin and the suture black, the black more or less dilating at the scutellum ; the apex is rather acutely produced and is not emarginate.- The black marks on the elytra vary : there appears always to be a black spot on the shoulder; this spot sometimes extends itself obliquely towards the suture, and sometimes expands so much as to unite with the black at the scutellum ; there is also frequently a spot behind the middle of each elytron, sometimes forming a large black patch. Most nearly allied to A. lansbergi, Salle, but less elongate. 22. ALURNUS CASSIDEUS, Westw. Ann. Nat. Hist. 1841, viii. p. 204. Two examples with entirely black elytra. Specimens brought by Mr. Buckley, in a former collection, have the elytra more or less rusty yellow, in which they agree more nearly with the original type. The type of this species is said to come from Mexico, and, according to a sketch in Prof. Westwood's possession, is much broader in the elytra than the specimens from Ecuador. As, however, there seems to be some doubt as to the correctness of the locality given for the type, and as the specimens from Ecuador vary somewhat in form, I think it best at present to consider them all one species. 23. ARESCUS LABIATUS, Petty, Del. Anim. p. 101, pi. 20. f. 7. Hab. Sarayacu ; Ega, Nauta, St. Paulo. 24. ARESCUS PERPLEXUS, Baly. (Plate XXX. fig. 14.) This species differs from A. labiatus in having the antennae black, with the basal joints pale beneath ; the basal joint has the projection obliquely truncate, so that it is obtuse instead of being acute ; the thorax is rather more deflexed at the anterior angles, and has a slight impression at the base before the scutellum. The interantennal process of the forehead is rather short and broad, truncate in the PROC. ZOOL. Soc-1881, No. XVIII. 18 |