Novel, non-solanaceous hostplant record for Manduca sexta (Lepidoptera: Sphingidae) in the Southwestern United States

Field observations in the Tucson, AZ, basin reveal that Manduca sexta (L.) has been incorrectly described in the past as a specialist herbivore that oviposits and feeds exclusively on plants in the family Solanaceae. We present evidence that previously unreported, non-solanaceous host-plants are routinely used by M. sexta females for oviposition. These plants permit successful larval development, through to emergence of the next generation of adults. The novel hostplants. 2 species of the genus Proboscidea, belong to the Martyniaceae, a family taxonomically distant from the Solanaceae. Our observations on oviposition and larval feeding were conducted during 2 consecutive field seasons. During the 2nd field season, we counted M. sexta eggs on native hostplants, both solanaceous (Datura wrightii, Regel) and non-solanaceous (2 Proboscidea species), and found higher abundance of eggs on the Proboscidea spp., in approximately a 3:1 ratio. Our results challenge the commonly held view that M. sexta is a specialist exclusively on solanaceous plants.