THE ARGUS TORTOISE BEETLE 1 
By F. H. Chittenden 
Entomologist, Truck-Crop Insect Investigations, Bureau of Entomology, United States 
Department of Agriculture 
INTRODUCTORY 
The foliage of sweet potato, wherever planted in the United States, is 
attacked every year by tortoise beetles of different species, the largest 
of which is known as the Argus tortoise beetle (Chelymorpha cassidea 
Fab.). 2 This species breeds on convolvulaceous plants, and, until the 
year 1919, was rather generally believed to be more commonly found 
on bindweed (Convolvulus spp.) or wild morning-glory (Ipomoea spp.) 
Fig. i. —The Argus tortoise beetle: a , Beetle; 6, larva with feci-fork extended at end; c, pupa, ventral 
view; d, dorsal view of pupa with characteristic covering. Greatly enlarged. 
and related wild plants than on sweet potato. That year the species 
was abundant and attracted more attention on sweet potato (Ipomoea 
batatas) than on wild plants, and recent studies tend to show that it 
prefers the cultivated plant, even when wild Convolvulaceae are available 
in the immediate vicinity. Thus far, however, it has not been a pest of 
importance. 
DESCRIPTION 
THE BEETLE 
The beetle (fig. i, a, and PI. i, A, a) is dark brick red when fully 
mature, and, before it is fully colored, of different shades of yellow. Its 
1 Accepted for publication, Nov. i, 1923. 
* Formerly known as Chelymorpha argus Ticht.; order Coleoptera, family Chrysomelidae. 
Journal of Agricultural Research, 
Washington, D. C. 
( 43 ) 
Vol. XXVII, No. 1 
Jan. s, 1924 
Key No. K-123 
