Diagnostic Features |
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Distribution | Recent, Antarctic and subantarctic. |
Name gender | feminine |
Type | Parapneustes cordatus Koehler, 1912, p. 161, by subsequent designation of Fisher, 1966, p. U598. |
Species Included |
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Classification and/or Status | Spatangoida, Paleopneustina, incertae sedis B. |
Remarks | Mortensen (1951) saw no reliable distinction between this taxon and Tripylus. However, the architecture of the plastron is very different, with the type species of Tripylus having a short and wide labral plate that extends no further back than ambulacral plate 1, whereas Parapneustes has a stout, subquadrate labral plate, almost as long as the sternal plates, which extends back to the third or fourth ambulacral plate. It also differs in having marginal and peripetalous fascioles separated. It comes closest to Amphipneustes in test architecture, but is distinguished from that taxon by retaining fascioles into adulthood. De Ridder et al. (1992) provide a discussion of this genus. Koehler, 1912. Echinodermes (Asterias, Ophiures et Echinides). Deuxieme Expedition Antarctique Francaise (1908-1910), 16, 1-270 pp., 26 pls. Mortensen, T. 1951. A monograph of the Echinoidea V. Spatangoida 2. C. A. Reitzel, Copenhagen. De Ridder, C., David, B., & Larrain, A. 1992. Antarctic and Subantarctic echinoids from \'Marion Dufresne\' expeditions MD03, MD04, MD08 and from the \'Polarstern\' expedition Epos III. Bulletin du Musee national d\'Histoire naturelle, Paris 4e serie 14, 405-441. |