Feather Star
Common Name: Feather Star
Scientific Name: Crinoid
Phylum: Echinodermata
Class: Crinoidea
Other Taxonomy:
Specimen #: 47
Circumstance: Observed online
Specimen Condition: Specimen condition presumed alive
Location: Found on reef of Batu Moncho Island (online)
Typical Habitat: Marine environments
Invasive? Not an invasive species
Natural area of growth: Marine environments
Relationship with humans:
Evolutionary Significance: Crinoids are dioecious, with separate male and female individuals. They have no true gonads, producing their gametes from genital canals found inside some of the pinnules. The pinnules eventually rupture to release the sperm and eggs into the surrounding sea water. The fertilised eggs hatch to release a free-swimming vitellaria larva. The larva is barrel-shaped with rings of cilia running round the body, and a tuft of sensory hairs at the upper pole. In some cases females have been known to temporarily brood the larvae using chambers within the arms. The larva does not feed, and lasts only for a few days before settling to the bottom and attaching itself to the underlying surface using an adhesive gland on its ventral surface. The larva then metamorphoses into a stalked adult. Even the free-swimming feather stars sometimes go through this stage, with the adult eventually breaking away from the stalk Within 10 to 16 months the crinoid will be able to reproduce.
Feeding Mechanism: Crinoids feed by filtering small particles of food from the sea water with their feather like arms
Sources:
Scientific Name: Crinoid
Phylum: Echinodermata
Class: Crinoidea
Other Taxonomy:
Specimen #: 47
Circumstance: Observed online
Specimen Condition: Specimen condition presumed alive
Location: Found on reef of Batu Moncho Island (online)
Typical Habitat: Marine environments
Invasive? Not an invasive species
Natural area of growth: Marine environments
Relationship with humans:
- Fossilised crinoid columnal segments extracted from limestone quarried on Lindisfarne, or found washed up along the foreshore, were threaded into necklaces or rosaries, and became known as St. Cuthbert's beads.
- In the Midwestern United States, fossilized segments of columnal crinoids are sometimes known as Indian beads
- Crinoids are the state fossil of Missouri
Evolutionary Significance: Crinoids are dioecious, with separate male and female individuals. They have no true gonads, producing their gametes from genital canals found inside some of the pinnules. The pinnules eventually rupture to release the sperm and eggs into the surrounding sea water. The fertilised eggs hatch to release a free-swimming vitellaria larva. The larva is barrel-shaped with rings of cilia running round the body, and a tuft of sensory hairs at the upper pole. In some cases females have been known to temporarily brood the larvae using chambers within the arms. The larva does not feed, and lasts only for a few days before settling to the bottom and attaching itself to the underlying surface using an adhesive gland on its ventral surface. The larva then metamorphoses into a stalked adult. Even the free-swimming feather stars sometimes go through this stage, with the adult eventually breaking away from the stalk Within 10 to 16 months the crinoid will be able to reproduce.
Feeding Mechanism: Crinoids feed by filtering small particles of food from the sea water with their feather like arms
Sources: