| Phylum | Echinodermata |
| Class | Asteroidea |
| Order | Valvatida |
| Family | ophidiasteridae |
| Gender | Hacelia |
| Species | attenuated |
Hacelia attenuata
(Gray, 1840)
- Orange star (I)
- Smooth starfish (EN)
- Glatter Seestern (D)
- Étoile de mer lisse (FR)
- Estrella de mar lisa (ES)
- Gladde zeester (NL)
Size : It can reach 25-30 cm in diameter.
Depth : Lives from a few meters up to 150.
Distribution : Mediterranean thermophilic species, therefore it is not very common in the northern part and more common in the eastern and southern part. Other sources indicate it as present throughout the Atlantic Ocean, on both sides, from Greenland to Patagonia, but this contradicts the claim that the species is basically thermophilic, that is, a lover of warm waters.
Living habits : Sciaphile species, during the day it takes refuge in caves or small caves. It feeds on sponges.
Environments where it is possible to observe it : It lives in poorly lit rocky environments.
Identification criteria : The arms are long and slender, ending with a conical tip. On the arms there are plates of contrasting color, usually darker, placed longitudinally.
Complementary morphological description : The disc is small with respect to the arms. the coloring is red or yellow-orange. The lower side, the oral one, is more yellow, especially near the ambulacral furrows. The body is uniformly covered with granules and the oral side plates are slightly hollowed out.
Possible confusions: It could be confused with the red star (Echinaster sepositus) or with the snake star (Ophidiaster ophidianus), none of which, however, presents contrasting coloring on the arms.
Curiosity and observations : Reproduction takes place between June and September.
