Life History of the Looper Phigalia titea1 in Virginia2

The half-wing geometer, Phigalia titea Cramer, is an obscure hardwood defoliator occurring in the eastern half of the United States. An outbreak in the mountains of northwestern Virginia provided an opportunity to obtain information on the life history and natural enemies of this insect. P. titea has 1 generation a year. The insect overwinters as a pupa in the soil. Adult emergence occurs from late March to mid-April, and oviposition occurs in this same period. Hatching takes place in late April and the larvae feed for approximately 1½ months. Head-width measurements and individual rearing data of P. titea larvae reveal that this species progresses through 5 instars during larval development. Pupation occurs in late May and early June in the litter near the soil surface. Descriptions of the immature stages are given. The following parasites were recovered: Telenomus alsophilae Viereck, Apantales palcacritae Riley, A. murtfeldtae Ashmead, Hypopteromalus tabacum Fitch, Pimplopterussp., and Tachinomyia sp. Several of these are new host records.