Meeting Abstract

16.6  Jan. 4  Colonization of Caves by Flightless Hawaiian Moths MEDEIROS, M.J.; University of California, Berkeley m_j_m@berkeley.edu

Cave-adapted fauna are hypothesized to colonize separate caves either via available underground connections, or in independent invasions which result in speciation events, because individuals of a cave-adapted species are unlikely to survive in the epigean environment. This may be especially true in Hawaii, where lava tube caves on different islands are separated by kilometers of ocean and the cave fauna is typically flightless. To determine the number of independent cave colonization events and the number of times that flightlessness has evolved in a group of Hawaiian moths, I collected Schrankia (Noctuidae) individuals from seven caves on two different islands. A phylogeny based on approximately 1100bp of COI and a fragment of the nuclear gene �wingless� shows that surface Schrankia have invaded caves separately at least two times on the Big Island. In both of these cave species, at least some females were flightless when collected, suggesting that flightlessness has arisen through convergence. One of these two species, S. howarthi, is distributed across the Big Island and forms a clade along with cave Schrankia on Maui, where flightless females also occur. For this widely distributed species, underground connections do not appear to be the only mode of colonization of new caves, because on both Maui and the Big Island, some individuals were found living above ground as well. These individuals, which are capable of flight, provide an example of how a seemingly cave-adapted species is able to facilitate above-ground colonization of new caves that are separated by ecological barriers. This is the first example of a species that occurs deep in Hawaiian caves to be distributed on two separate islands.