1196 FAMILY LIII. CIIRYSOMELID.E. 



LVI. Phyllotreta Chev. 1831. (Gr., "leaf + bore.") 



Small elongate oval or oblont^-oval subconvex species, separated 

 from allied genera by characters pertaining to the hind tibiae as 

 mentioned in the generic key. They have the head small, deeply 

 inserted in the thorax; antennae half as long as body, or slightly 

 longer; thorax broader than long and somewhat narroM^ed in front; 

 elytra oval, the humeri never prominent, usually marked with a 

 yellowish white sinuous stri^je ; first joint of hind tarsus about one- 

 third the length of tibiae and equal to the other three; claws simple. 

 The males have the last ventral more or less impressed at tip. The 

 following species have been taken or should occur in the State. 

 All feed upon cruciferous plants, both cultivated and wild: 



Fig. 526. a, Antenna of Phyllotreta vlkei, male; h, P. robusla and antenna of male; c, P. sinuala and an 

 tenna of male; d, P. vittata and antenna of male; e, antenna of female of P. robusta, sinuala and vitlata; /, an- 

 tenna, male and female of pkta, bipustiJata, etc. (After Horn.) 



KEY TO INDIANA SPECIES OF PHYIXOTRETA. 



«. Fifth joint of autennfe longer than either the fourth or sixth ; tlie male 



with the fifth joint always, and sometimes the fourth, thickened, and 



elongate. 



J). Elytra piceous, without stripes; sixth joint of male antennae as long 



as the fourth and cylindrical. (Fig. 52(), a.) ulkei. 



bh. Elytra piceous, each with a yellowish stripe. 



c. Elytral stripe narrower ; lower angle of fifth joint not prolonged. 

 d. Stripes of elytra parallel with the suture on the basal half. 

 (Fig. 526, e.) 2212. sinuata. 



(M. Stripes of elytra incurved at base, approaching the scutellum. 

 (Fig. 526, d.) 2213. vittata. 



cc. Elytral stripe broad, at its apical third reaching side, apex and 

 suture ; lower angle of fifth antennal joint distinctly prolonged. 

 (Fig. 526, h.) 2214. robusta. 



aa. Fifth joint of antenuie never longer than sixth ; antenn?e not different 

 in the sexes, the joints gradually but slightly stouter from second to 

 tip. (Fig. 526, /.) 

 e. Elytra black and yellow. 



/. Elytra each with two oval yellow spots, one on humerus, the other 

 subapical. 2215. bipustulata. 



if. Elytra dull yellow with a common sutural stripe and narrow mar- 

 ginal line, black. 2216. aemoraci.e. 

 ee. Elytra unicolorous. 



