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Five new species of Homoscleromorpha (Porifera) from the Caribbean Sea and re-description of Plakina jamaicensis

Published online by Cambridge University Press:  10 April 2013

Alexander V. Ereskovsky ,
Dennis V. Lavrov  and
Philippe Willenz
Alexander V. Ereskovsky*
Affiliation:
Mediterranean Institute of Biodiversity and Ecology (IMBE), UMR 7263, Aix-Marseille Université, CNRS, IRD, Station Marine d'Endoume, Marseille, France Biological and Soil Science Faculty, Saint-Petersburg State University, Russia
Dennis V. Lavrov
Affiliation:
Department of Ecology, Evolution and Organismal Biology, Iowa State University, 253 Bessey Hall, Ames, IA, USA
Philippe Willenz
Affiliation:
Department of Invertebrates, Royal Belgian Institute of Natural Sciences, 29 rue Vautier, 1000 Brussels, Belgium
*
Correspondence should be addressed to: A.V. Ereskovsky, Mediterranean Institute of Biodiversity and Ecology (IMBE), UMR 7263, Aix-Marseille Université, CNRS, IRD, Station Marine d'Endoume, Marseille, France email: alexander.ereskovsky@imbe.fr
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Abstract

Five new species of Homoscleromorpha (Porifera) of four genera, Oscarella, Plakortis, Plakina and Corticium, are described from vertical walls of reef caves at depths ranging from 23 to 28 m in the Caribbean Sea. Oscarella nathaliae sp. nov. has a leaf-like thinly encrusting, flat body, loosely attached to the substrate and a perforated, not lobate surface. Oscarella nathaliae sp. nov. contains two bacterial morphotypes and is characterized by two mesohylar cell types with inclusions. Plakortis myrae sp. nov. has diods of two categories: abundant large ones (83–119 μm long) and rare small ones (67–71 μm long) with sinuous, S-bent centres; triods Y- or T-shaped (18–5  μm long), and abundant microrhabds (5–12 μm long). Plakortis edwardsi sp. nov. has diods of one category with thick, sinuous, S-bent centres (110 to 128 μm long); triods T-shaped (actines 28–59 μm long). It is the only species of this genus showing small diods (22–31 μm long). Plakortis dariae sp. nov. has diods of two categories: large ones (67–112 μm long) and small, rare, irregular ones, slightly curved, often deformed with one end blunt (30–59 μm long); triods rare and regular (actines 20–44 μm long). Corticium diamantense sp. nov. has oscula situated near its border, regular non-lophose calthrops of one size-class, very rare tetralophose calthrops and candelabra with the fourth actine ramified basally in 4–5 microspined rays. In addition, a re-description of Plakina jamaicensis is based on newly collected material and the type specimen. Plakortis jamaicensis has a convoluted brain-like surface; well developed sub-ectosomal cavities; irregular sinuous diods, triods, calthrops, rare monolophose calthrops, rare dilophose calthrops, rare trilophose calthrops and common tetralophose calthrops. Molecular ‘barcoding’ sequences for mitochondrial cob are given for Plakortis edwardsi sp. nov., P. dariae sp. nov., Plakina jamaicensis and Corticium diamantense sp. nov. An identification key for all western Atlantic Homoscleromorpha is provided.

Keywords

taxonomyPoriferaHomoscleromorphabiodiversityOscarellaPlakortisPlakinaCorticiumJamaicaMartinique

Information

Type
Research Article
Information
Journal of the Marine Biological Association of the United Kingdom , Volume 94 , Issue 2 , March 2014 , pp. 285 - 307
Copyright
Copyright © Marine Biological Association of the United Kingdom 2013 

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