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Zygometridae
''Zygometridae'' is a family of echinoderms belonging to the order Comatulida Comatulida is an order of crinoids. Members of this order are known as feather stars and mostly do not have a stalk as adults. The oral surface with the mouth is facing upwards and is surrounded by five, often divided rays with feathery pinnules. .... Genera: * '' Catoptometra'' Clark, 1908 * '' Zygometra'' Clark, 1907 References {{Taxonbar, from=Q17651575 Comatulida ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comatulida
Comatulida is an order of crinoids. Members of this order are known as feather stars and mostly do not have a stalk as adults. The oral surface with the mouth is facing upwards and is surrounded by five, often divided rays with feathery pinnules. Comatulids live on the seabed and on reefs in tropical and temperate waters. Taxonomy Bourgueticrinida, the sea lilies, has traditionally been viewed as an order of Articulata and a sister taxon to Comatulida. A study published in 2011 suggested that it should be renamed Bourgueticrinina and viewed as a suborder of Comatulida. Characteristics Like other echinoderms, comatulids have pentamerous symmetry (five sided) as adults though the larvae have bilateral symmetry. Late in their development, the larvae are attached to the seabed by a stalk, but this is broken at metamorphosis and the juvenile crinoid is free living. The body has an endoskeleton made from a number of articulated calcareous plates known as ossicles covered by a thin e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echinoderms
An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the sea lilies or "stone lilies". Adult echinoderms are found on the sea bed at every ocean depth, from the intertidal zone to the abyssal zone. The phylum contains about 7,000 living species, making it the second-largest grouping of deuterostomes, after the chordates. Echinoderms are the largest entirely marine phylum. The first definitive echinoderms appeared near the start of the Cambrian. The echinoderms are important both ecologically and geologically. Ecologically, there are few other groupings so abundant in the biotic desert of 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 complete regeneration from a single limb. Geolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
