Common starfish Common starfish The common starfish or common sea star ("Asterias rubens") is the most common and familiar starfish in the north-east Atlantic. Belonging to the family Asteriidae, it has five arms and usually grows to between 10–30 cm across, although larger specimens (up to 52 cm across) are known. The common starfish is usually orange or brown, and sometimes violet; deep-water specimens are pale. The common starfish is to be found on rocky and gravelly substrates where it feeds on molluscs and other benthic invertebrates. The common starfish normally has five arms, broad at their base and gradually tapering to
Asexual reproduction in starfish the disc begins to develop and eventually a madreporite appears. This process lasts for some time, and about 10 months after separation, the comet has a half disc and 4 arms about 1 cm (0.4 in) long. Asexual reproduction in starfish Asexual reproduction in starfish takes place by fission or through autotomy of arms. In fission, the central disc breaks into two pieces and each portion then regenerates the missing parts. In autotomy, an arm is shed which continues to live independently as a "comet", eventually growing a new disc and further arms. Only certain genera of starfish are able