Meeting Abstract

P2.209  Saturday, Jan. 5  The native range of Phallusia nigra: is it really black and white? VANDEPAS, LE*; ROCHA, RM; HIROSE , E; LEE, SCS; OLIVEIRA , LM; SWALLA, BJ; University of Washington; Universidade Federal do Paraná, Brazil; University of the Ryukyus, Okinawa, Japan; National University of Singapore; Universidade Federal do Paraná, Brazil; University of Washington lvandepa@uw.edu

Phallusia nigra (Savigny, 1816) is a cosmopolitan ascidian which has been described as introduced in a number of regions (India, Japan, Hawaii). Its native range is unknown, but the first published description was from the Red Sea (Savigny, 1816). The taxonomic description of P. nigra includes a striking smooth, black tunic and large size (up to 10 cm). However, there are at least two related Phallusia – P. philippinensis (Millar, 1975) and P. fumigata (Grube, 1864) – which can also have dark black tunics and then are difficult to discern from P. nigra. The distribution of P. nigra broadly overlaps with that of P. philippinensis in the Indo-Pacific and P. fumigata in the Mediterranean. As part of a 2011 NSF-PASI Tunicate Taxonomy course in Bocas, Panama, this group of ascidian biologists decided to investigate the range of P. nigra with morphological and molecular studies. We sequenced 18S ribosomal DNA and cytochrome oxidase B of individual ascidians from Singapore, Japan and Brazil. Our results show that these three species form a monophyletic group within the phlebobranch ascidians. This clade includes Phallusia mammillata, which has a very different external appearance (bumpy) and coloring (white). We examined historical reports and the present locations of P. nigra, P. fumigata, and P. philippinensis in the literature. We are interested in how these species display similar phenotypes and we are currently working to determine the native ranges of all four Phallusia species.