Echinoidea


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Echinoidea

[‚ek·ə′noid·e·ə]
(invertebrate zoology)
The sea urchins, a class of Echinozoa having a compact body enclosed in a hard shell, or test, formed by regularly arranged plates which bear movable spines.
References in periodicals archive ?
Optimizing food distribution in closed-circuit cultivation of edible sea urchins (Paracentrotus lividus: Echinoidea).
Descriptions of new species of Cainozoic Echinoidea from Jamaica.
Emlet, "Developmental mode and species geographic range in regular sea urchins (Echinodermata: Echinoidea)," Evolution, vol.
Macro-invertebrates present included squat lobster, Munida quadrispina; hermit crabs (Paguriidae); spot shrimp, Pandalus platyceros; bryozoans; hydroids; brachiopods; seawhips (Pennatulacea); seastars (Asteroidea); brittlestars (Ophiuridae); sea urchins (Echinoidea); sea cucumbers (Holothuridae); and gastropods, in addition to the sponges.
Responses of ovaries and testes of Lytechinus variegatus (Echinodermata: Echinoidea) to dietary administration of estradiol, progesterone and testosterone.
The Echinodermata are represented by a number of groups: Crinoidea, represented by articulated calyxes and disarticulated columnals and brachials; Blastoidea, represented by columnals and calyxes, especially those of Pentremites conoideus; Echinoidea, represented by disarticulated interambulacral plates as well as several largely intact specimens; and Asteroidea, represented by one nearly complete specimen, as well as disarticulated dorsal plates from the same species.
Facultative planktotrophy in the tropical echinoid Clypeaster rosaceus (Linnaeus) and a comparison with obligate planktotrophy in Clypeaster subdepressus (Gray) (Clypeasteroida: Echinoidea).