Jarhead starred Jake Gyllenhaal as a U.S. Marine.
A pedicellaria -LRB- plural  : pedicellariae -RRB- is a small wrench - or claw-shaped appendage with movable jaws , called valves , commonly found on echinoderms -LRB- phylum Echinodermata -RRB- , particularly in sea stars -LRB- class Asteroidea -RRB- and sea urchins -LRB- class Echinoidea -RRB- .. Echinodermata. Echinodermata. Asteroidea. Asteroidea. Echinoidea. Echinoidea. Each pedicellaria is an effector organ with its own set of muscles , neuropils , and sensory receptors and is therefore capable of reflex responses to the environment .. organ. organ ( anatomy ). muscles. muscles. neuropils. neuropils. sensory receptors. sensory receptors. Pedicellariae are poorly understood but in some taxa , they are thought to keep the body surface clear of algae , encrusting organisms , and other debris in conjunction with the ciliated epidermis present in all echinoderms .