Primitive starfish, such as " Astropecten " and " Luidia ", swallow their prey whole and start to digest it in their cardiac stomachs.
12.
It is distinguished from Astropecten spinulosus by very different superomarginal plates : highest, defined and equipped with very big and strong superomarginal spines and they have very different plates.
13.
Primitive starfish, such as " Astropecten " and " Luidia ", swallow their prey whole, and start to digest it in their cardiac stomachs.
14.
Secondly, the general appearance of the starfish and the colour are usually different : Astropecten spinulosus is always slenderer and dark brown with superomarginal spines brown and inferomarginal spines blue-purple.
15.
It is distinguished from Astropecten bispinosus mainly for the superomarginal spines far from the inside edge of plates and they leave on top, on the base of them, a small bare area.
16.
Young specimens of Astropecten platyacanthus sometimes can be confused with Astropecten jonstoni for the appearance and the colour, but it is always easy to distinguish them by very different superomarginal plates and superomarginal spines.
17.
Young specimens of Astropecten platyacanthus sometimes can be confused with Astropecten jonstoni for the appearance and the colour, but it is always easy to distinguish them by very different superomarginal plates and superomarginal spines.
18.
Paxillae are small pillar-shaped ossicles with flat tops sometimes found covering the aboral surface of sea stars such as " Luidia ", " Astropecten " and " Goniaster " that live underneath sediment.
19.
Some burrowing species from the genera " Astropecten " and " Luidia " have points rather than suckers on their long tube feet and are capable of much more rapid motion, " gliding " across the ocean floor.
20.
"" Pecten maximus " swims but this is generally limited to escape reactions, the main predators which cause this reaction when the scallop detects them are the mollusc eating starfish " Asterias rubens " and " Astropecten irregularis " while starfish which do not feed on molluscs cause limited jumping or valve-closing reeactions.
