GENERAL HISTOLOGY

Detailed explanation-1: -brittle star, also called serpent star, any of the 2, 100 living species of marine invertebrates constituting the subclass Ophiuroidea (phylum Echinodermata). Their long, thin arms-usually five and often forked and spiny-are distinctly set off from the small disk-shaped body.

Detailed explanation-2: -Brittle stars belong to Class Ophiuroidea (Phylum Echinodermata) and have radial symmetry, with five elongate, skinny arms extending from their central disc, or body.

Detailed explanation-3: -The Ophiuroidea or brittle stars, basket stars (euryalids with branching arms) and snake stars (euryalids with non-branching arms), are the largest group among extant echinoderms, with 2064 described species [1], found in all oceans from the intertidal to the greatest depths.

Detailed explanation-4: -Echinoderms, which are exclusively marine animals, are divided into five classes, the Asteroidea (starfishes), Ophiuroidea (serpent-stars), Echinoidea (sea-urchins, heart-urchins, and sand-dollars), Holothuroidea (sea-cucumbers), and Crinoidea (sea-lilies and feather-stars).