Life History of a Mesquite Looper, Semiothisa cyda (Lepidoptera: Geometridae), in Central Texas1

Abstract

Larvae of the geometrid moth, Semiothisa cyda (Druce), fed on the foliage of honey mesquite trees, Prosopis glandulosa Torrey. Females laid an average of 279 eggs each, and a generation required 34 days in the laboratory at 25°C: 3.8 days for the egg, 19 for the larva, 7.2 for the pupa, and 4 days for the adult to reach peak oviposition. Populations in the laboratory increased 1.13 times per day and doubled each 5.5 days. Larvae had five or six instars and ate 17 cm2 of leaf material each (ca. one mesquite leaf, including some material killed but not eaten). Full-grown larvae were 24 mm long and pupated under litter on the soil surface. In cages on trees, one larva per one or two leaves produced 50% defoliation, and two larvae per leaf produced 95% defoliation.