LARVAL DEVELOPMENT IN THE ASTEROID ECHINASTER ECHINOPHORUS

摘要: 1. Echinaster echinophorus off the west coast of Florida was observed to spawn, from early April late July, two different egg types: one type is pelagic, brown black in color and 1.0-1.3 mm diameter, while second bright orange, ranges 0.84 0.88 diameter settles immediately substratum after spawning.2. The present study reports on external morphogenesis eggs type.3. Cleavage stages occurred rapidly at laboratory temperature 25° C with gastrula being reached 24 hours fertilization. By 48 a modified brachiolaria develops 4 larval arms central sucker. Folding preoral lobe toward oral surface 7 days growth reported for first time Echinaster.4. A chronology juvenile development presented.5. Larval rates expressed as lengths (mm) well ray wet weights (mg) are presented.