Evasterias troschelii  is a diecious species that spawns freely into the ocean most often while aggregated.  Spawning usually occurs between April 11 and July 1.  The eggs are whitish in color and around 150 µm in diameter.  About five days after fertilization E. troschelii becomes free-swimming (between the blastula and gastrula stages) and develops into a bipinnaria larvae that is unique to Class Asteroidea.  Bipinnaria larva have locomotor bands and projections (arms) that arise from the body surface.  The bipinnaria larva eventually becomes a brachiolaria larva with the appearance of three additional arms at the anterior end.  These arms are short, ventral in position, and covered with adhesive cells at the tip.  The three arms and the sucker represent an attachment device, and the brachiolaria then settles to the bottom. Metamorphosis then takes place and the anterior end of the larva degenerates and forms only an attachment stalk. The adult body of the sea star develops from the rounded, posterior end of the larva. All the parts of E. troschelii are then formed (ex.  mouth, esophagus, intestine, anus, water vascular system, podia, etc.).  Evasterias troschelii has amazing regeneration powers.  It is able to regenerate a whole new sea star from as little as 1/5 of the central disc and an arm.

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