Five-armed sea star, with thin arms and a small radial disc.
Red and gray mottled coloration.
The normal number of limbs is five, but can have anywhere from one to nine.
Arms are often not symmetrical, due to ability to regrow new arms and discs.
Maximum size is 4 inches in diameter.
Southern California to Peru.
Ecuador (Galapagos Islands).
May also be present in Hawaii.
Lives in the rocky intertidal.
Found at depths of 0 to 500 feet.
Embryos hatch into biradially symmetric (foldable on one line of symmetry) planktonic larvae that later transform into pentaradially symmetric (foldable on five lines of symmetry) juveniles with stubby arms.
Sea stars eat mollusks and detritus.
Fragile sea stars are considered rather inedible, although sea stars can be eaten by seabirds, fish, crabs, otters, and even other sea stars.
The fragile star is known to undergo autotomy, or self-amputation, where one arm detaches itself from the disc. That arm then regrows a new disc and new arms, a process that can take six months or more to complete. This is often why fragile stars look asymmetrical – they are in the process of regrowing their bodies!
Sources: darwinfoundation.org; Reef Life Survey; Between Pacific Tides: Fifth Edition; National Aquarium; Benthic Invertebrates of Four Southern California Marine Habitats; sealifebase.ca