and Central American Malachiidae and Melyridae. 91 



Key to the Mexican and Guatemalan species of Trichochrous 

 (= Pristoscelis, Gorh.). 



A. Prothorax with the lateral margins con- 



spicuously serrate, crenulate, or hooked, 

 and sometimes greatly elongated, in (^ ; 

 tibiae feebly, sparsely spinulose; an- 

 tennae with joints 7-10 broad, strongly 

 serrate [Ckadytes, Casey.] 



a. Prothorax ((J) subquadrate, with dis- 



tinct anterior angles. 

 a^. The lateral margins sharply serrate 



anteriorly denticulatus, n. sp. 



b^. The lateral margins sharply hooked 



anteriorly hamatus, n. sp. 



b. Prothorax {^) very elongate, the an- 



terior angles obliterated, the lateral 



margins closely crenulate anteriorly . crenulatus, n. sp. 



B. Prothorax with the lateral margins not 



conspicuously serrate in (J, at most 

 obsolete crenulate in the two sexes . [Trichochrous, 



Motsch.] 



c. Antennae abruptly serrate from joint 5, 



the latter not or very little broader than 

 6 (except in T. fuscovittatus). 

 c^. Tibiae closely, strongly spinulose; 

 antennae and legs stout, antennal 

 joints 5-10 becoming progressively 

 wider. 

 a^. Upper surface with intermixed 

 erect black setae. 

 a^. Femora, tibiae, and tarsi rufes- 



cent, body wholly black . . fulvipes, Gorh. 

 b^. Femora infuscate, tibiae, tarsi, 



and elytra rufescent . , • . rufipeniiis, Lee. 

 b^. Upper surface without intermixed 

 erect setae, the hairs semierect. 

 c*. Elytra rufescent or violaceous ; 

 prothorax strongly rounded at 

 sides ; vestiture coarse and in 

 great part pale .... arcuaticollls, n. sp. 

 (P. Elytra cyaneous ; prothorax less 

 rounded at sides ; vestiture 

 fuscous cyanipennis, n. sp. 



