Chemical defense against predation in an insect egg.

The larva of the green lacewing (Ceraeochrysa cubana) (Neur tera, Chrysopidae) is a natural predator of eggs of UtethE ornatrix (Lepidoptera, Arctiidae), a moth that sequesters pyrrc idine alkaloids from its larval foodplant (Fabaceae, Crotalaria sp Utetheisa eggs are ordinarily endowed with the alkaloid. Alkale free Utetheisa eggs, produced experimentally, are pierced by larva with its sharp tubular jaws and sucked out. Alkaloid-lai eggs, in contrast, are rejected. When attacking an Utetheisa E cluster (numbering on average 20 eggs), the larva subjects it to inspection process. It prods and/or pierces a small number of el (on average two to three) and, if these contain alkaloid, it pas "negative judgement" on the remainder of the cluster and tu away. Such generalization on the part of the larva makes ser because the eggs within clusters differ little in alkaloid contE There is, however, considerable between-cluster variation in ( alkaloid content, so clusters in nature can be expected to rai widely in palatability. To check each cluster for acceptability m therefore be adaptive for the larva, just as it must be adaptive Utetheisa to lay its eggs in large clusters and to apportion alkal evenly among eggs of a cluster.

Main Author: Eisner, Thomas.
Other Authors: Eisner, Maria., Rossini, Carmen., Iyengar, Vikram., Roach, Braden.
Language: English
Published: 2000
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