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

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, Syn...

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Bibliographic Details
Main Author: Esnal, Graciela Beatriz
Language:unknown
Published: 1998
Subjects:
ice
Online Access:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_09541020_v10_n2_p147_Tatian
https://hdl.handle.net/20.500.12110/paper_09541020_v10_n2_p147_Tatian
Description
Summary: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.