26 Memoirs on the Coleoptera 



Costovia n. gen. 



The type of this genus is moderately small in size, not at all 

 unlike the species of Lydamis in general appearance, with identical 

 scutellum — flat and cuspid medially at apex — and feebly concave, 

 loosely squamulose abdomen at base; it is therefore very surprising 

 that the strangely Balanimis-Mke beak and mandibles are observable 

 in profile, and the antennal club is wholly different from that of 

 the preceding genus, the club being very elongate and cylindric, 

 gradually pointed apically; the funicle is also much more elongate 

 and slender, the first four joints much, the fifth slightly, elongated. 

 The type is the following: 



Costovia tenuirostris n. sp. — Body oval, only faintly subrhombic in outline, 

 convex, piceous, the beak, except basally, and the tarsi black, feebly shining and 

 rather strongly sculptured; vestiture above in great part accidentally denuded 

 in the type, the scales beneath close, rather broad and yellowish, largely denuded 

 on the metasternum and side-pieces, smaller and sparser on the abdomen basally; 

 beak distinctly more than half as long as the body, very slender, strongly arcuate, 

 cylindric, smooth, nude and nearly punctureless throughout, attached near the 

 lower limit of the eyes; antennae a little behind basal third, slender; prothorax 

 short, three-fourths wider than long, rapidly conical, with broadly arcuate sides, 

 the broadly and feebly constricted apex distinctly less than half as wide as the 

 base, the basal lobe wide and truncate; punctures strong, dense and longitudinally 

 confluent; median line narrow, nude, polished and slightly convex, not carini- 

 form and extending from basal fourth very nearly to the apex; scutellum trans- 

 verse, cuspid at apex exactly as in Lydamis; elytra ovoidal, rather obtuse behind, 

 only a fourth longer than wide, fully a fourth wider than the prothorax; striae 

 moderate, deep, punctured along the bottom; intervals feebly convex and coarsely, 

 densely punctured, all of them distinctly carinulate, some becoming nearly 

 simple basally, the humeral strongly for some distance; legs strongly and closely 

 punctured, the femora moderately clavate, the spicule distinct, the general type 

 as in Lydamis, but with straight and basally connate claws. Length ( 9 ) 5.8 

 mm.; width 3.2 mm. Brazil (Chapada — forest). November. One specimen. 



It is to be regretted that almost the entire upper surface is 

 denuded of pubescence in the only known specimen. 



The beak in this genus is exactly as in Balaninus, and projects 

 from the lower part of the head in the same way; the mandibles are 

 nearly similar and, in the latter genus, the anterior coxae are also 

 in close contact. In every other respect, however, there is radical 

 divergence; the strongly ascending mes-epimera, large and trans- 

 verse, posteriorly aciculate scutellum, connate tarsal claws and 

 shape of the prothorax are all very different in the two genera. It 

 undoubtedly constitutes, in fact, a most interesting case of con- 

 formity in development in certain parts of the body, brought about 

 by similar life habits in two distinctly different subfamily groups. 



