The Complete Development of the Deep-Sea Cidaroid Urchin Cidaris blakei (Agassiz, 1878) With an Emphasis on the Hyaline Layer
Datum
2009-12
Autor:innen
Zeitschriftentitel
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Verlag
University of Oregon
Zusammenfassung
Living echinoids comprise two major sister clades, the Euechinoidea and the
Cidaroidea. Cidaroids first appeared during the lower Permian (~255 mya) and are
considered to represent the primitive form of all other living echinoids. The present
study of Cidaris blakei, a deep-sea planktotrophic cidaroid urchin, provides a description
of development from fertilization through early juvenile stages and is the first report of a
deep-sea organism reared through metamorphosis. Cidaris blakei resembles other
cidaroids in its lack of a cohesive hyaline layer, the absence of an amniotic invagination
for juvenile rudiment formation, and the presence of a single spine morphotype at
metamorphosis. Cidaris blakei differs from other cidaroids in the presence of an apical tuft, the extent of fenestration of postoral skeletal rods, the shape of juvenile spines and an extended (14 day) lecithotrophic stage prior to development of a complete gut.
This study includes my co-authored materials.
Beschreibung
xv, 63 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.
Schlagwörter
Sea urchins, Cidaroida