Introduced and native Phlebobranch and Stolidobranch solitary ascidians (Tunicata: Ascidiacea) around Salvador, Bahia, Brazil
M. Rocha, RosanaY.K. Bonnet, NadiaS. Baptista, MariahS. Beltramin, Fabiele
The Port of Salvador (12°58'S, 38°30'W) receives cargo ships from different regions such as southeast Asia, North Atlantic, Mediterranean, Africa, North and South America. Thus, the presence of this port enhances the probability of new species arriving and establishing in Todos os Santos Bay (TSB), in which the port is located. Ascidians are sessile filter-feeding invertebrates with short lived larvae and thus are good indicators of bioinvasion. We surveyed the ascidian fauna on three different occasions: August 1999, June 2004 and December 2007. Nineteen species were identified belonging to the following families: Ascidiidae (Phallusia nigra, Ascidia cf. multitentaculata, A. nordestina, A. papillata, A. scalariforme, A. cf. tapuni, A. tenue), Corellidae (Rhodosoma turcicum), Pyuridae (Microcosmus anchylodeirus, M. exasperatus, M. helleri, Pyura vittata, Herdmania pallida), and Styelidae (Polycarpa cf. reviviscens, P. spongiabilis, P. tumida, Polycarpa sp., Styela canopus, Cnemidocarpa irene). Only A. nordestina, A. papillata, A. scalariforme and P. spongiabilis are possibly native to this region, while P. tumida and C. irene were classified as introduced. Microcosmus anchylodeirus, H. pallida, P. vittata, M. exasperatus, M. helleri, S. canopus, A. cf. multitentaculata, A. tenue and P. nigra were classified as cryptogenic. Most are widely distributed in all oceans and their native geographic distribution is unknown, while A. cf. multitentaculata and A. tenue occur only in the Atlantic, with disjunct distributions. Polycarpa cf. reviviscens, P. tumida and M. anchylodeirus are registered for the first time on the coast of Brazil. Colonial ascidians from this collection are still being studied. The large number of cryptogenic and introduced species indicates the necessity of monitoring TSB for expansion of these populations and the need for the establishment of control programs.
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