334 PROCEEDINGS OF THE NATIONAL MUSEUM vor,. 99 



ately emarginate in front. Antenna extending to middle of prono- 

 tum; segment 1 elongate, as long as following 3 segments united; 

 segment 2 globose ; segments 3 and 4 slightly longer than wide ; seg- 

 ments 5-11 compact, strongly transverse, twice as wide as long, and 

 subequal in length and width to one another. 



Pronotum twice as wide as long, distinctly narrower at apex than 

 at base, widest in front of middle ; sides broadly rounded anteriorly, 

 more strongly converging posteriorly, with the margins narrow and 

 visible anteriorly from above; disk moderately convex above, nar- 

 rowly, transversely depressed on each side along anterior margin, 

 broadly, shallowly depressed at middle on basal half, with a broad, 

 oblique depression on each side extending forward from base to mid- 

 dle near lateral margin ; surface coarsely, confluently alveolate-punc- 

 tate toward sides, and sparsely clothed with long, erect, inconspicuous 

 hairs. 



Elytra moderately convex, transversely flattened along base, at 

 base slightly wider than pronotum at base ; sides nearly parallel along 

 basal halves, then arcuately converging to the tips, which are con- 

 jointly broadly rounded ; lateral margins coarsely serrate behind mid- 

 dles. Surface rather densely, irregularly punctate basally, striately 

 punctate posteriorly, striae deeply impressed toward apices, the punc- 

 tures in the striae separated from one another by about one-half 

 their own widths ; interstrial spaces on sutural regions slightly con- 

 vex, two to three times as wide as the strial punctures, wider and more 

 strongly convex toward sides, rather coarsely, sparsely, regularly 

 punctate, with a moderately long, fine, erect, white hair arising from 

 each puncture. 



Abdomen beneath finely, densely punctate, more sparsely punctate 

 on basal sternites, rather densely clothed with moderately long, fine, 

 erect and recumbent, white hairs; intervals indistinctly granulose; 

 last visible sternite broadly rounded at apex, without a subapical 

 carina. Prosternum coarsely, densely, deeply punctate at middle, 

 coarsely ocellate-punctate at sides, rather densely clothed with long, 

 fine, semierect, white hairs ; anterior margin emarginate. 



Length 7 mm., width 2.4 nrni. 



Type locality. — Rio Balsas, Guerrero, Mexico. 



Tyye.~\]. S. N. M. No. 58787. 



Described from a single specimen collected August 16, by H. F. 

 Wickham. 



This species belongs to Horn's Emarginatae group. It is allied to 

 Acmaeodera horni Fall but differs from the description given for that 

 species by being smaller, and of a uniformly dark brown color, and 

 in having the upper surface of the body clothed with white hairs, 

 the pronotum at the middle distinctly wider than the elytra, obliquely 



