Beautiful Feather Star

Like many other crinoids, C. bella is visually comparable to both a flowering plant and a sea star. This species evolutionary morphology has remained fairly constant with minimal changes in their appearance.

Cenometra bella typically occupies shallow tropical waters, living in open-surfaces below depths of 5 meters. They are more commonly located around large coral species in coral reefs, and sometimes found in the intertidal zone. However, in rare cases, they have been found to establish habitat in the deeper ocean (up to 55m). These featherstars are often exposed on top of a gorgonian coral, under a reef flat, or clinging to sea whips.

This shallow water species is present in the Indo-West Pacific Ocean, thriving around South and South East Asia: India, the Philippines, China, South Japan, the Maldives, South Pacific Islands. C. bella has also been found in the Great Barrier reef.

The beautiful crinoid is a suspension feeder. They filter feed on marine microorganisms like algae, diatoms, and larvae. They also consume marine snow (detritus). This filtration occurs on their cirri, which is linked to the gut near the mouth and anus on the centrodorsal plate.

These featherstars are mostly sessile, anchoring themselves to hard substrate surfaces or the sea floor using their cirri ‘legs’. However, they are also free-moving creatures capable of traveling short distances to escape their predators or other threats. As nocturnal critters, they partially hide, sessile, within rocks and corals during the day with their mouths oriented upwards. Though their centrodorsal plate remains sheltered during the day as they wait till night to come out and feed, their free-arms can remain fully exposed in a circular fan-like arrangement outside of their habitat, throughout the day.

There are male and female sexes of C. bella. These gonochoric crinoids shed their ova or sperm from ruptured pinnules into the water. After fertilisation, their embryos grow into larvae that later sink to a substrate surface, like gorgonian coral. The growing larvae, once attached to a surface undergoes metamorphosis into a small crinoid and remains mostly sessile during growth.

Being mainly sessile creatures, C. bella is highly susceptible to predators like large fish and other marine organisms. They may also lose limbs due to abiotic stressors like great salinity and temperature fluctuations. On average, the feather-star is reported to lose an arm every 8 to12 days. As a survival mechanism, this crinoid has evolved to be able to lose and regenerate lost limbs, much like a sea-star. Their pinules are also spiked to protect them from predators. In addition, C. bella are able to produce aversive tasting and toxic chemicals to deter predators from consuming their arms that remain exposed out of their habitat throughout the day. The deterrent taste not only provides immediate protection from their predators but also forms long-term negative conditioning to prevent large fish from attacking again.