The Adratic Sea is one of the few places in the Mediterranean Sea where this species can be easily seen. This coral has polyps with a smooth cup and a maximum of 30 retractile tentacles. These tentacles have urticant cells, with which the coral paralyzes its preys before eating them.
Astroides calycularis is an encrusting coral with a characteristic orange colour, commonly found in shallow rocky habitats. It forms rounded encrusting colonies of about 10cm height and 25-30cm of diameter on rocks, cavities and cave entrances, starting from a depth of 1 metre up to 50 metres. The polyps are 1-2cm in size, star shaped.
They can be seen all year round along the Istrian coasts.