Common name: Eight-Armed Seastar
Scientific name: Meridiastra calcar
Date observed: 25th March 2017
Time of day observed: Morning
Size: Arm radius up to 50 mm
Location: Windang Island
Zone: Low intertidal
Number encountered: A few
Interactions within species: These seastars are often found resting in informal groups. They are opportunistic feeders, moving out as the tide changes to scavenge detritus and hunt for snails.
Interactions with other species: They are predators of small marine gastropods, which share a similar space on the intertidal zone. Eight-Armed Seastars can capture snails in their suckered arms, and hold the snail tight enough to crush and digest it.
Notes: They prefer not to be exposed to open air, and will seek water if placed on dry rock. They can move with surprising swiftness.