The Echinodermata is one of the best characterized and most distinct phyla of animal kingdom. The echinoderms being common and conspicuous marine animals have been known since ancient times. They are found at every ocean depth from the intertidal zone to the abyssal zone. The first definitive members of the phylum appeared near the start of the Cambrian period. The echinoderms are important both biologically and geologically: biologically because few other groupings are so abundant in the biotic desert of the deep sea, as well as the shallower oceans, and geologically as their ossified skeletons are major contributors to many limestone formations, and can provide valuable clues as to the geological environment.
This is a guide to common echinoderms found in the waters around the Andaman and Nicobar Islands.
1. General introduction
2. Literature review
3. Characteristic of extant classes
4. Study areas
5. Material and methods
6. Key characters
Checklist of echinoderms of India