Polymastiidae (Demospongiae: Hadromerida) with ornamented exotyles: a review of morphological affinities and description of a new genus and three new species

All polymastiid sponges displaying ornamented exotyles are reviewed and their morphological affinities are reconsidered. The study embraces all known species of Proteleia , Sphaerotylus , Trachyteleia and Tylexocladus as well as several species of Polymastia . A new genus, Koltunia , is established...

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Bibliographic Details
Published in:Journal of the Marine Biological Association of the United Kingdom
Main Authors: Plotkin, Alexander, Morrow, Christine, Gerasimova, Elena, Rapp, Hans Tore
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 2016
Subjects:
Online Access:http://dx.doi.org/10.1017/s0025315416000655
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0025315416000655
Description
Summary:All polymastiid sponges displaying ornamented exotyles are reviewed and their morphological affinities are reconsidered. The study embraces all known species of Proteleia , Sphaerotylus , Trachyteleia and Tylexocladus as well as several species of Polymastia . A new genus, Koltunia , is established for the Antarctic species Proteleia burtoni based on the unique shape of distal ornamentations of its giant exotyles and on the absence of a spicule palisade in its cortex, a rare feature among the polymastiids. Three new species of Sphaerotylus are described – S. renoufi from the British Isles, S. strobilis from South Africa and S. tjalfei from West Greenland. Transfer of one New Zealand species from Polymastia to Proteleia and of one Chilean species from Polymastia to Sphaerotylus is proposed. The present study provides a background for future integrative phylogenetic analyses based on comprehensive molecular and morphological datasets which should reveal the natural relationships between the polymastiid taxa.