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Radiasteridae
Radiasteridae is a family of echinoderms belonging to the order Paxillosida The Paxillosida are a large order of sea stars. Characteristics Paxillosida adults lack an anus and have no suckers on their tube feet. They do not develop the brachiolaria stage in their early development.Matsubara, M., Komatsu, M., Araki, T .... Genera: * '' Betelgeusia'' Blake & Reid, 1998 * '' Gephyriaster'' * '' Indiaster'' Raghavendra Rao, 1957 * '' Radiaster'' Perrier, 1881 References Paxillosida Echinoderm families {{Asteroidea-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echinoderms
An echinoderm () is any animal of the phylum Echinodermata (), which includes starfish, brittle stars, sea urchins, sand dollars and sea cucumbers, as well as the sessile sea lilies or "stone lilies". While bilaterally symmetrical as larvae, as adults echinoderms are recognisable by their usually five-pointed radial symmetry (pentamerous symmetry), and are found on the sea bed at every ocean depth from the intertidal zone to the abyssal zone. The phylum contains about 7,600 living species, making it the second-largest group of deuterostomes after the chordates, as well as the largest marine-only phylum. The first definitive echinoderms appeared near the start of the Cambrian. Echinoderms are important both ecologically and geologically. Ecologically, there are few other groupings so abundant in the deep sea, as well as shallower oceans. Most echinoderms are able to reproduce asexually and regenerate tissue, organs and limbs; in some cases, they can undergo compl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paxillosida
The Paxillosida are a large order of sea stars. Characteristics Paxillosida adults lack an anus and have no suckers on their tube feet. They do not develop the brachiolaria stage in their early development.Matsubara, M., Komatsu, M., Araki, T., Asakawa, S., Yokobori, S.-I., Watanabe, K. & Wada, H. (2005) The phylogenetic status of Paxillosida (Asteroidea) based on complete mitochondrial DNA sequences. Molecular Genetics and Evolution, 36, 598–605 They possess marginal plates, and have sessile pedicellariae. They mostly inhabit soft-bottomed environments of sand or mud. Systematics Recent analyses suggest Paxillosida may be a sister taxon of Asterina. The order is divided into these families: * family Astropectinidae Gray, 1840 * family Benthopectinidae Verrill, 1899 * family Ctenodiscidae Sladen, 1889 * family Goniopectinidae Verrill, 1889 * family Luidiidae Sladen, 1889 * family Paleobenthopectinidae Blake, 1984 † * family Porcellanasteridae Sladen, 1883 * family ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betelgeusia
''Betelgeusia'' is an extinct genus of sea stars in the family Radiasteridae. It was described by Blake and Reid, in 1998, and existed in what is now the Netherlands, Texas, United States, Morocco, and India, during the Middle Jurassic through the Cretaceous period. It contains the species ''B. brezinai'', ''B. exposita'', ''B. riedi'', and ''B. orientalis''. References External links ''Betelgeusia''at the Paleobiology Database The Paleobiology Database (PBDB) is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms. History The Paleobiology Database originated in the NCEAS-funded Phanerozoic Marine Pale ... Fossil taxa described in 1998 Jurassic echinoderms Prehistoric life of Europe Middle Jurassic genus first appearances Cretaceous genus extinctions Prehistoric starfish genera Paxillosida {{paleo-asteroidea-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
