2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 94 



species along lines other than those at present used will result in more 

 clean-cut genera. There is a greater diversity of structure displayed 

 among the species of PhyUophaga than between those of Phytahis and 

 Chlaenobia. 



Pending a reinvestigation of the whole complex, the five genera 

 of Rhizotrogini known to occur in the New World may be separated 

 as follows : 



1. Claws of front and middle legs simple, those of hind legs cleft 



Chirodines Bates. 

 All tarsal claws toothed, cleft, pectinate or serrate 2. 



2. Tarsal claws cleft 3- 



Tarsal claws toothed, pectinate or serrate 4- 



3. Protborax somewhat narrowed at base ; female pygidium usually profoundly 



modified ; tarsi usually with dense pubescence on plantar surfaces 



Chlaenobia Blanchard. 



Protborax wider across basal angles than across anterior angles ; female 



pygidium not modified ; tarsi without dense pubescence on plantar surfaces 



Phytalus Erichson. 



4. Tarsal claws strongly bipectinate or feebly serrate, sometimes with a more 



or less well developed subapical tooth on one or both of the claws of 



a foot Listrochclns Blanchard. 



Tarsal claws neither pectinate nor serrate, with a more or less strongly 

 developed tooth which may be subbasal, median, or subapical in position 



PhyUophaga Harris. 



CHLAENOBIA Blanchard 



Blanchard, 1850, Cat. Coll. Ent. Paris, Coleopt., vol. i, p. 116; Lacordaire, 1856, 



Gen. Coleopt., vol. 3, p. 265 ; Bates, 1888, Biol. Centr.-Amer., Coleopt., 



vol. 2, pt. 2, p. 166; Arrow, 1933, Ann. Mag. Nat. Hist., Ser. 10, vol. 11, 



p. 146. 



Type species. — Chlaenobia ciliatipes Blanchard 1850 (monobasic; 



also by subsequent designation of Arrow 1933). 



KEY TO THE SPECIES OF CHLAENOBIA BLANCHARD 185O 

 MALES 



1 . Antenna nine-segmented 2. 



Antenna ten-segmented 3- 



2. Spurs of posterior tibia short, straight, and tapering aeyrota Bates. 



Spurs of posterior tibia somewhat spatulate and twisted, the spur more re- 

 mote from the insertion of tarsus strongly hooked at apex. . .arrowi n. sp. 



3. Metasternum sparsely set with bristles, the portion adjacent to the median 



line glabrous or nearly so 4- 



Metasternum moderately hairy to very densely pilose, with never more than 

 a small spot on median line glabrous ; plantar surface of second segment of 

 anterior tarsus pilose ; pronotum unicolorous 5- 



