Astropecten platyacanthus

Astropecten platyacanthus is a sea star characterized by its narrow and high superomarginal plates, which are covered with scales and small spines. Each plate typically has one strong, irregularly shaped spine that is often yellow or orange. The species exhibits considerable variability in appearance, with colors ranging from dark brown to olive green, pink-brown, or bluish-grey on the aboral side, while the oral side is usually yellow-brown. It can reach a diameter of 9 to 12 cm, with exceptional specimens measuring up to 18 cm. This species is often confused with others in its genus, particularly Astropecten bispinosus and Astropecten spinulosus, due to similarities in size and shape, but can be distinguished by the configuration and characteristics of its spines and plates. Astropecten platyacanthus inhabits the Mediterranean Sea, primarily on mobile seabeds composed of sand, mud, or gravel. It is commonly found at depths ranging from 1 to 60 meters, with a preference for mixed coarse sand and mud at depths of 1 to 4 meters. This species is nocturnal, actively hunting for bivalve mollusks during the night, although it can also be observed during the day, particularly in the early morning and late afternoon. Reproduction occurs through both sexual and asexual means, with embryos developing into planktonic larvae before settling and metamorphosing into juvenile sea stars. Encounters with Astropecten platyacanthus during dives are often rewarding, especially at night when they are more active. The conservation status of this species is not evaluated, and it can be found in various dive sites across the Mediterranean.