Evasterias echinosoma is a species of starfish belonging to the family Asteriidae. This species is commonly found in the intertidal and subtidal zones of the Pacific coast of North America, from Alaska to California.
Description & Characteristics
Evasterias echinosoma is a relatively large starfish, with a maximum arm span of up to 30 centimeters (12 inches). It has a distinctive, five-pointed star shape with a central disc and five arms. The upper surface of the starfish is covered in numerous spines, giving it a rough texture. These spines are arranged in radial rows along the arms and can vary in size and shape. The coloration of Evasterias echinosoma can be highly variable, ranging from reddish-brown to yellowish-orange, with individuals often displaying mottled patterns or even faint stripes.
Habitat and Occurrence
Evasterias echinosoma is typically found in intertidal and subtidal habitats, ranging in depth from the low tide line to depths of over 100 meters (328 feet). It is a common inhabitant of rocky shores, kelp forests, and sandy bottoms, making it a prevalent presence in these aquatic ecosystems.
Taxonomy
The species Evasterias echinosoma belongs to the family Asteriidae, which encompasses a diverse group of starfish found worldwide. Evasterias echinosoma is classified within the order Forcipulatida, a group of starfish characterized by the presence of specialized pincers called pedicellariae on their body surface. This order is further nested within the Class Asteroidea, which represents the broader group of starfish and their relatives.
Feeding
Evasterias echinosoma is a carnivorous predator and is an opportunistic feeder, consuming a variety of prey items. Its diet consists mainly of invertebrates, including mussels, barnacles, clams, snails, and other starfish. It uses its strong arms and tube feet to pry open bivalve shells and capture other prey. The Evasterias echinosoma‘s ability to quickly digest its prey allows it to efficiently utilize its food sources.
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