Ascidians (Tunicata, Ascidiacea) of Potter Cove, South Shetland IsIands, Antarctica

MARCOS TATIÁN; RICARDO SAHADE; MARCELO DOUCET; GRACIELA ESNAL

ANTARCTIC SCIENCE

Año: 1998 vol. 10 p. 147 - 152

0954-1020

Certain physical factors, substrate type and ice action appear to be important determinants for ascidian distribution. Three different substrate types were sampled at depths between 0-30 m by SCUBA diving: soft bottoms, hard bottoms and moraine deposits. The species found were Aplidium radiutum, Synoicum adureanum, Distapiiacyiindrica, Sycozoagaimardi, Sycozoasigiliinoides, Tylobranchion speciosum, Corella eumyota, Ascidia chaliengeri, Cnemidocurpa verrucosa, Styela wundeli, Dicarpa insinuosa, Pyura bouvetensis, Pyura discoveryi, Pyura obesa, Pyura setosu, Molgula enodis and Molgulapedunculata. Highest diversity and patchy distribution was found in less stringent environments, where epibiosis is a commmon phenomenon on stolidobranch ascidians. Differences in stalk development were found in the most abundant species Moiguiapedunculuta and Cnemidocurpa verrucosa. Ice action may be the main factor that determines the absence of ascidians above 15 m in all the stations sampled0-30 m by SCUBA diving: soft bottoms, hard bottoms and moraine deposits. The species found were Aplidium radiutum, Synoicum adureanum, Distapiiacyiindrica, Sycozoagaimardi, Sycozoasigiliinoides, Tylobranchion speciosum, Corella eumyota, Ascidia chaliengeri, Cnemidocurpa verrucosa, Styela wundeli, Dicarpa insinuosa, Pyura bouvetensis, Pyura discoveryi, Pyura obesa, Pyura setosu, Molgula enodis and Molgulapedunculata. Highest diversity and patchy distribution was found in less stringent environments, where epibiosis is a commmon phenomenon on stolidobranch ascidians. Differences in stalk development were found in the most abundant species Moiguiapedunculuta and Cnemidocurpa verrucosa. Ice action may be the main factor that determines the absence of ascidians above 15 m in all the stations sampled