Coscinasterias muricata
0-84m
36 sites
Asteriidae
Imagine encountering a starfish... but with up to eleven arms! That's the Eleven-armed Sea Star (Coscinasterias muricata), a fascinating find for divers and snorkelers exploring the waters of Southern Australia and the South Pacific. While not the most vibrant creature on the reef, its unique morphology and behaviour make it a memorable sighting. These sea stars inhabit benthic zones, meaning they are found on the seafloor, from the shallows down to depths of 84 meters, so keep your eyes peeled at all depths. Although its diet is currently unknown, the Eleven-armed Sea Star does not appear to be afraid of divers. Keep an eye out for its unique method of asexual reproduction by fission, where it can regenerate lost limbs or even split into two separate individuals. This may be why they have such a variable number of arms! With a diver appeal of only 2/5, they might not be the 'star' of the show, but spotting one of these quirky creatures adds a unique dimension to any dive.
The most obvious identifying feature is, of course, the number of arms, which ranges from 7 to 11 – far more than the typical five-armed starfish. While size data is unavailable, they are known for their irregular, often asymmetrical shape due to their method of asexual reproduction. They are typically found in shades of brown or beige, blending in with the seafloor. Look closely for the slightly rough texture of their skin.
393 sites
