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A phylum of Metazoa that includes starfish, sea urchins, sea lilies, and other classes. All but the sea cucumbers (Holothuroidea) are basically radially symmetrical and most possess a calcareous endoskeleton with external spines. They inhabit the sea bottom, some near shore, others in deep water.
[echino- + G. derma, skin]
References in periodicals archive ?
In thin sections the AMB 1 facies display a packstone depositional fabric in which the bioclstic components are dominated by the fusulinid forams (24%), brachiopod (14%), bryozoan (10%), bivalve (1%) and echinoderm 1%.
Gray triggerfish had a diverse diet, composed of 131 different prey taxa that were combined into 19 broader taxonomic groups: gastropods, amphipods, decapods, unidentified crustaceans, polychaetes, bivalves, bryozoans, barnacles, bony fishes, echinoderms, tunicates, miscellaneous items (e.
Much of the research on yolk proteins in echinoderms has focused on the Echinozoa subphylum and less on the Asterozoa subphylum.
4K) is mainly composed of fecal pellets (50-100[micro]m), but in contrast to facies F2A, it also contains minor micritic intraclasts (50-200[micro]m), scarce small agglutinated forams and miliolids, scarce highly fragmented fossil remains (bivalves, brachiopods, echinoderms and serpulids) and scarce quartz grains (<5%) and, in addition, displays current and wave ripples.
Rahman's scans revealed that the earliest echinoderms had a body plan that was bilaterally symmetrical, where one side mirrors the other.
The most primitive echinoderms were characterized by flattened, nearly bilaterally symmetrical forms.
Corals, echinoderms and molluscs above all react very sensitively to a decline in the pH value.
Even with modest water movement, this can occur in but a few minutes, yet sperm viability is known from hatchery operations to be on the order of tens of minutes to more than 1 h, which is greater than that typically observed for echinoderms (again, the records in Farley (2002) suggest a maximum of 20-30 min).
After collection, the animals were transported to the laboratory and fixed in formalin 10%, being deposited in the Echinoderm section of the Paulo Young Invertebrate Collection, at the Federal University of Paraiba (CIPY-UFPB).
The sanitary agreement on fish, fishery products, live bivalve molluscs and echinoderms (live or not) for human consumption, and on by-products, such as fishmeal or fish oil, is meant to authorise Greenland to sell these products in the Union based on internal market rules, on the condition of applying EU rules on public health and, where necessary, sanitary policy rules on fishery products, live bivalve molluscs and by-products from these sources.
The availability of long term data sets for tropical echinoderms is rare in the literature, and published reports deal maily with the description of benthic population patterns over the annual cycle, as in M.