492 BULLETIN 182, UNITED STATES NATIONAL MUSEUM 



form; gular sutures united; neck one-third as wide as liead; margin 

 of pronotum double, upper line very feeble in front; presternum with 

 a pair of large sclerites in front of the sternite; elytral suture some- 

 what beveled; middle coxae widely separated; posterior coxae con- 

 tiguous, "triangular"; first abdominal sternite absent, second repre- 

 sented only by a small sclerite at sides; intersegmental membrane of 

 abdomen marked with a pattern of angular areas in longitudinal 

 bands. 



Remarks. — This genus is known from South and Central America. 

 It can be readily distinguished from all other Xantholinini known 

 to me by the dense umbilicate punctures of the head and pronotum. 



Only one species has been found in our region and this one only 

 in Trinidad. 



1. PLOCHIONOCERUS BRACHYPTERUS Sharp 



Plochionocerus brachypterus Shaep, 1885, p. 471. — Bebnhaueb and Schubest, 

 1914, p. 315. 



Description. — Black. Head oval, basal angles completely rounded ; 

 eyes at nearly four times their length from base; labrum feebly 

 emarginate at middle; underside elevated at sides and middle; gular 

 sutures united from near base; punctures distinctly umbilicate, very 

 dense. Pronotum seven-twelfths as wide as long, widest at anterior 

 third, thence parallel to completely rounded basal angles; with an 

 impressed midline, one-third as wide as neck in front but narrowed 

 posteriorly; rest punctured similarly to head. Elytra very densely 

 punctate, the intervals convex but not united. {Abdomen finely, 

 moderately densely, submuricately punctured. Length, 17 mm.) 



Type locality. — Guatemala. 



Types. — In the British Museum. 



Records. — ^The following are the records known to me : 



Trinidad: (Bryant, in British Museum), Blanch is.seuse (Morrison, in U.S.N.M.). 

 Central America: Guatemala, Me:xico, Honduras, Panam.\ (Sharp, 1885; 

 U.S.N.M.). 



Specimens examined. — Besides the type series and other Central 

 American specimens I have seen only one example in the British 

 ISIuseum and one in the United States National Museum. 



Remarks. — The Trinidad specimen upon which the description is 

 based is without abdomen, and the characters in parentheses were 

 obtained from a Central American example. Altliough this species 

 is not known from South America, it will almost certainly be found 

 along the northern coast, since the Central American and Trinidad 

 examples seem to be identical. 



I find no record of the habits of this species. 



