Nutritional particles are caught by
ambulacral tentacles located along the entire length of the ambulacrum.
Characters examined include general body appearance, encrusting ossicles, pedicellariae, madreporite, abactinals, terminals, marginals, intermarginals, actinals, oral frame,
ambulacral grooves and interambulacrals, papulae, tube feet, digestive tract, and its development.
The emergence of plates related to the
ambulacral system follows the Ocular Plate Rule.
Tiene el celoma muy desarrollado: celoma epigastrico, celoma hipogastrico y sistema
ambulacral, hemal y perihemal.
Legs (Figs 13-16): All legs with
ambulacral claws and bearing smooth setae on all segments except tarsi.
The dorsal surface of this species is characterized by a series of irregularly positioned papillae of different sizes and shapes (Dendy 1896, Sewell 1987), although the ventral surface is smoother, with the presence of
ambulacral podia, or tube feet, which are used for locomotion (Dendy 1896, Sewell 1987).
Surco
ambulacral estrecho, las placas interambulacrales tienen una hilera de espinas internas pequenas, digitiformes, varias en cada placa, y una serie externa de espinas mas grandes, dos en cada placa.
Legs: bear short, smooth and needle-like setae, leg I without
ambulacral prolognation.
The monophyly of the genus Echinocardium is based on two synapomorphies: an anal branch is added to the subanal fasciole, and the labrum is short and bordered by two pairs of
ambulacral plates.
Ambulacral grooves descend from the arms, run along the surface of the visceral mass, and unite at the centrally located mouth (Fig.
Legs (Figs 22-25): All legs with
ambulacral claws, all setae on legs smooth.
columbiana was related to an unusual defense in which the snail inserted its proboscis deep into one of the sea star's
ambulacral grooves and bit the radial nerve.
ambulacral - pertaining to the ambulacra of radial echinoderms