Implications of Larval Movements in Declining Butterflies: Investigating Methods of Tracking First Instar Larvae

DeRosa University Center, Ballroom

Morphological studies of adult Speyeria callippe have revealed extensive wing pattern variation that has been classified into 19 described subspecies. Interestingly, other sympatric Speyeria species often resemble S. callippe across its range, which extends from British Columbia to Manitoba down to northern Baja Mexico. This color pattern similarity may be the result of color pattern mimicry or crypsis. Because adult wing patterns are so variable, and potentially involved in adaptive coloration, they may obscure relationships within S. callippe and among Speyeria species generally. Immature stages are subject to different ecological pressures than adults, and may offer an independent perspective to test systematic hypotheses. Previous work in our lab has detected differences between larval morphology of subspecies from the California coast ranges compared with subspecies from mountainous regions in southern Oregon and the Sierra Nevada foothills. However, sampling was limited in the previous analysis with only a couple mountain taxa represented. This project expands sampling to examine whether consistent morphological differences exist between geographic subspecies within California, as well as outside of California. Our additional sampling of subspecies from California, Nevada, Colorado, Oregon, and Alberta allows us to reexamine 1) the correlation of larval morphology with existing subspecies taxonomy, 2) whether larval characters provide information for elucidating subspecies relationships, and 3) whether strong morphological differences exist that suggest the presence of cryptic species.