STUDIES ON THE BIOLOGY OF THE CHRYSOPIDAE 
II. THE FEEDING BEHAVIOR OF THE 
ADULT OF GHRYSOPA CARNEA (NEUROPTERA) 1 ’ 2 
By Joseph K. Sheldon 3 and Ellis G. MacLeod 
Department of Entomology, University of Illinois, Urbana, Illinois 
Introduction 
Although it has long been known that the larvae of the Chryso- 
pidae are obligate predators of small, soft-bodied arthropods, the 
feeding habits of their adults have never been studied in detail. The 
adults of such species as C. chi Fitch, C. incompleta Banks, C. oculata 
Say, C. nigricornis Burmeister, and C. quadripunctata Fitch are 
believed to feed primarily, like their larvae, on living prey (Smith, 
1922; Burke and Martin, 1956; MacLeod, unpubl.). On the other 
hand, adults of a number of other species, including C. earned 
Stephens, will not accept such food, although several other substances 
are readily consumed. 
Smith (1922) maintained adults of C. earned (=C. plorihunda 
Fitch) on a weak sugar solution plus crushed aphids, but he did not 
ascertain the separate contributions of these dietary items toward 
adult survival or toward yolk deposition in the female. Finney 
(1948), whose studies were the first to be directed toward develop- 
ing methods for the mass rearing of C. carnea for biological control, 
found that a diet consisting solely of honey resulted in a very low 
level of oviposition, but when this food was supplemented with a 
coccid honeydew a much higher level was achieved. Neumark ( 1952) 
reported obtaining similar “high” levels of oviposition using aphid 
honeydew as the sole food, while Sundby (1966, 1967) was success- 
ful in maintaining adults and securing reasonable numbers of eggs 
from females which were fed upon a diet of honey and pollen. 
As Finney’s mass rearing procedures had proven uneconomical 
because of the difficulty of obtaining adequate supplies of honeydew, 
Hagen (1950) investigated several alternatives. After establishing 
that the difference in the fecundity of adults fed either honey or 
honeydew alone was not due to quantitative or qualitative differences 
Tart I of this series appeared in 1967. J. Insect Physiol. 13: 1343-1349. 
This work was supported by a grant from the National Science Founda- 
tion (GB 8644). 
3 Present address: Dept, of Biology, Eastern Baptist College, St. Davids, 
Pa. 19087. 
Manuscript received by the editor, May 12, 1971. 
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