Myelastrum = Medullary starrulet; μύελος, ἄστρον.
Pentalastrum = Little sea-star with five rays; πέντε, ἅλς, ἄστρον.
Pentinastrum = Starrulet with five rays; πέντε, ἴνος, ἄστρον.
Pentophiastrum = Starrulet with five snakes; πέντε, ὄφις, ἄστρον.
Hexalastrum = Little sea-star with six rays; ἕξα, ἅλς, ἄστρον.