LIFE-HISTORY AND DESCRIPTIONS OF IMMATURE STAGES OF NEASPILOTA-VIRIDESCENS QUISENBERRY (DIPTERA, TEPHRITIDAE) ON NATIVE ASTERACEAE IN SOUTHERN CALIFORNIA

Neaspilota viridescens Quisenberry is a multivoltine, oligophagous tephritid reproducing in flower heads of species of Aster, Chrysopsis, Chrysothamnus, Erigeron, Gutierrezia, Haplopappus, and Machaeranthera in the tribe Astereae and Lepidospartum in the tribe Senecioneae of the Asteraceae in California. The larvae feed mainly on the ovules and immature achenes as first and second instars; however, as third instars, they usually extend their feeding chambers into the receptacle and additionally feed on sap. The chamber walls of plant fragments become impregnated with excess sap and liquid feces that harden when dry to protect the overwintering larvae. Neaspilota viridescens mainly overwinters as a diapausing "prepuparium," a non-feeding, mostly quiescent, fully grown third instar with its gnathocephalon retracted. The egg, first, second and third instar larvae, prepuparium, and puparium are described and figured. Premating and mating behavior is described, including the use of the asymmetrical foretarsi of the male. Nuptial gift formation and presentation by the male also's described as part of courtship behavior.