There are three types of skeletons: the endoskeleton, the exoskeleton and the hydrostatic skeleton. Most cnidarians, flatworms, nematodes and annelids have a hydrostatic skeleton that consists of fluid held under pressure in a closed body compartment. ... Arthropods have a joint exoskeleton, the cuticle.

Does annelida have exoskeleton?

The exoskeleton is composed of a thin, outer protein layer, the epicuticle, and a thick, inner, chitin-protein layer, the procuticle. ... Annelids have a thin chitinous cuticle covering their bodies but it is not as well developed as in arthropods.

What animal has an exoskeleton?

All arthropods (such as insects, spiders and crustaceans) and many other invertebrate animals (such as shelled mollusks) have exoskeletons. Lobsters, for example, have tough outer shell systems which provide rigidity and shape to their bodies.