Meeting Abstract

49.7  Jan. 6  Larval Metamorphosis of Phestilla spp. in Response to Water Soluble Cues RITSON-WILLIAMS, R.*; PAUL, V.J.; Smithsonian Marine Station at Fort Pierce; Smithsonian Marine Station at Fort Pierce williams@sms.si.edu

In marine systems many invertebrates depend on their larvae for dispersal and to find the appropriate habitat for adult survival, yet the mechanisms of habitat choice remain poorly understood. In Hawaii, the nudibranch Phestilla sibogae only feeds on Porites compressa and is known to metamorphose in response to a water soluble cue from this coral. We tested four different Phestilla species to determine if their larvae metamorphosed in response to whole coral fragments or to water soluble compounds from coral fragments (coral water). In Guam, Phestilla sibogae metamorphosed at high rates to coral water from multiple species of Porites corals. Phestilla melanobrachia metamorphosed at similar rates to its prey Tubastrea aurea coral polyps and coral water. Phestilla minor could distinguish between Porites spp. coral water but also had high rates of metamorphosis in response to filtered seawater. Phestilla sp. 2, which feeds on some species of Gonipora, had high rates of metamorphosis in response to Goniopora fruticosa coral water. Phestilla sp. 2 could distinguish among different species of Goniopora and only had high rates of metamorphosis to coral waters made with its preferred prey. All of the Phestilla spp. tested recognized host coral waterborne cues and most of these species required them for metamorphosis.