A re-evaluation of morphological characters of the invasive ascidian Corella eumyota reveals two different species at the tip of South America and in the South Shetland Islands, Antarctica

• Published in: Polar Biology
• Main Authors: Alurralde, Roque Gastón, Torre, Luciana, Schwindt, Evangelina, Castilla, Juan C., Tatian, Marcos
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer
• Subjects: Ascidia; Corella Eumyota; Corella Antarctica; Morphologu; Multivariated Analyzes; Antarctica; South America; https://purl.org/becyt/ford/1.6; https://purl.org/becyt/ford/1; Antarctic; South Shetland Islands; Argentina; Marcos; Torre; Antarc*; Polar Biology
• Online Access: http://hdl.handle.net/11336/7609

The native solitary ascidian Corella eumyota Traustedt, 1882) is commonly found in the Southern Hemisphere in the cold-temperate waters of the Subantarctic and Antarctic regions. Its recent spread into the Northern Hemisphere throughout the NE Atlantic gave the species the status of invasive. Together with its widespread distribution, reports on its wide variability (several distinct morphological characters, genetic discontinuities and also possible misidentifications) cast doubt on the taxonomic status of different populations of this species. This work, based on the observation, quantification and analysis of specific morphological characters in specimens collected at five different localities of South America and Antarctica, strongly indicates that there are two different species: C. eumyota from South America and Corella antarctica Sluiter, 1905) from Antarctica, which has been till now considered a junior synonym of the former. The species clearly differ in the arrangement of the gonadal ducts, the size of the larvae and the shape of the anus, among other characters. Morphological variation displays a defined, discrete grouping supporting a clear differentiation into two species. This result shows the need for careful inspection of specimens to avoid wrong interpretations in a context of changes of marine biota due to biological invasions. Fil: Alurralde, Roque Gastón. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina. Museo Provincial de Ciencias Naturales ‘‘Dr. Arturo Umberto Illía’’; Argentina Fil: Torre, Luciana. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Diversidad y Ecologia Animal; Argentina Fil: Schwindt, Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Castilla, Juan C. Pontificia Universidad Católica de Chile; Chile Fil: Tatian, Marcos. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y ...