INJURIOUS AND BENEFICIAL INSECTS OP CALIFORNIA. 



273 



THE OBSCURE TWELVE-SPOTTED CUCUMBER BEETLE 



Diabrotica 12-punctata tenella (Leconte) 



(Diabrotica tenella Leconte) 180 



(Fig. 263) 



Description. — In size and shape this beetle greatly resembles the 

 twelve-spotted cucumber beetle, but is easily recognized by the dark 

 green wing covers, which are marked with 

 very small or obscure black spots. In some 

 species only a few faint spots show, while in 

 others no spots at all appear. The prothorax 

 is greenish or bright yellow, the head dark 

 green or black, the body yellow and the legs 

 and antennae yellowish green or brownish. 

 The eggs, larvae and pupae, though unde- 

 seribed, probably vary little from those of 

 D. 12-punctata. 



Life History. — The life history is practi- 

 cally the same as for D. 12-punctata. 



Nature of Work. — The nature of the work 

 is the same as that of the other species of 

 Diabrotica. 



Food Plants.— Like the two previous spe- twelve-spotted cucumber 



,!•• i^n -i i i» i beetle, Diabrotica 12-punctata 



cies, this is a general feeder and may be found tenella Lee. Adult, greatly 

 upon almost any of the crops, including enlarged. (Original) 

 alfalfa, barley, corn, cucumber, pea, squash, mnskmelon, watermelon, 

 sorghum, potatoes, weeds and fruit trees. 



Distribution. — This beetle occurs only in the southeastern part of 

 the State, having been taken most frequently in Imperial County. 



Control. — Control measures as recommended for D. soror and D. 

 12-punctata should be employed in controlling this beetle if remedies 

 prove necessary. 



263. 



The obscure 



THE WESTERN STRIPED CUCUMBER BEETLE 

 Diabrotica trivittata Mannerheim 



(Fig. 264) 



Description.— As seen by the illustration (Fig. 264), this beetle is 

 entirely different in general appearance from the previously described 

 species of Diabrotica. The adults are of the same general shape, but 

 slightly larger, being about f inch in length. The elytra are pale yel- 

 lowish with three black longitudinal stripes, as shown. The pro- 

 thorax is yellow, as are also the bases of the femora of the legs 

 and the basal half of the first antennal article. The body is shiny 

 black. This form is closely related to the Eastern striped encumber 

 beetle (D. vittata Fab.), but does not, appear to be quite as destruc- 

 tive. 187 



Life History. — The adults hibernate or feed largely through the 

 winter, especially in the southern part of the State, where they remain 



180 Townsend, C. H., Insect Life, V, p. 39, 1892. . nr 



"'Chittenden, F. H., Bui. No. 82, Pt. VI. Bur. Ent., U. S. Dept. Agric, p. 75. 1910. 



18—13664 



