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

• Main Authors: Tatian, M., Sahade, R.J., Doucet, M.E., Esnal, G.B.
• Format: Journal/Newspaper
• Language: unknown
• Subjects: Antarctica; Ascidiacea; Distribution; Diversity; Ice action; Substrate types; community composition; environmental factor; ice; spatial distribution; substrate; South Shetland Islands; Potter Cove; Aplidium radiatum; Ascidia challengeri; Cnemidocarpa verrucosa; Corella eumyota; Dicarpa insinuosa; Distaplia cylindrica; Molgula enodis; Molgula pedunculata; Pyura bouvetensis; Pyura discoveryi; Pyura obesa; Pyura setosa; Styela wandeli; Sycozoa gaimardi; Sycozoa sigillinoides; Synoicum adareanum; Tylobranchion speciosum; Antarc*
• Online Access: https://hdl.handle.net/20.500.12110/paper_09541020_v10_n2_p147_Tatian

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 radiatum, Synoicum adareanum, Distaplia cylindrica, Sycozoa gaimardi, Sycozoa sigillinoides, Tylobranchion speciosum, Corella eumyota, Ascidia challengeri, Cnemidocarpa verrucosa, Styela wandeli, Dicarpa insinuosa, Pyura bouvetensis, Pyura discoveryi, Pyura obesa, Pyura setosa, Molgula enodis and Molgula pedunculata. Highest diversity and patchy distribution was found in less stringent environments, where epibiosis is a common phenomenon on stolidobranch ascidians. Differences in stalk development were found in the most abundant species Molgula pedunculata and Cnemidocarpa verrucosa. Ice action may be the main factor that determines the absence of ascidians above 15 m in all the stations sampled. Fil:Esnal, G.B. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.