Diving with Feather Stars

Lanta Marine Life | Articulata

Feather stars are found at all coral reefs around Koh Lanta in a range of colours, including black and white, pink, purple, yellow, white and orange. Some species have multiple colours and patterns.

Feather stars, also popularly known as sea lilies, start life with a stalk or stem, which they shed as they grow into adults. As adults, they usually have between 5 and 40 arms, depending on the species, and can regenerate lost or damaged arms, similar to starfish.

The feathery arms are called pinnules and the pinnules curl in while the feather star rests, and spreads out when they feed or swim. Cirri are tiny legs on the end of the pinnules that help to attach them to substrates.

Like other echinoderms, feather stars exhibit radial symmetry with their mouth located at the centre, feeding on tiny organisms like plankton and ocean detritus by spreading their arms in a fan shape.

2 species found on this page:

Noble Feather Star (Comaster Nobilis)
Variable Bushy Featherstar (Comaster schlegelii)

Noble Feather Star

(Comaster Nobilis)

Comaster nobilis @ Koh Bida

Sometimes known as the Yellow Feather Star, this species may occur in a number of colour variations, but usually has 35 - 40 yellow arms. There are sometimes black, green, or white speckles on the under surface close to the centre.

The Noble feather star feeds on detritus, phytoplankton and zooplankton. The larvae of this feather star swim freely with plankton for a few weeks, then they settle down growing into a stalked form. Mature specimens break the stalk becoming free-living.

The Comaster nobilis has a wide range, occurring throughout the Indo-Pacific region.

Variable Bushy Featherstar

(Comaster schlegelii)

Comaster schlegelii @ Koh Bida

The variable bushy feather star has five rays attached to the upper part of the body, each subdivided into a number of feathery arms called pinnules. When one of these is lost, two grow in its place.

The colour is very variable, some specimens being plain golden yellow, pale brown or black and others being multicoloured, often green with bands of orange, white and black on the arms and pinnules.

They are most commonly found in the shallowest areas of the reef, usually down to around 5 m.

Juveniles often keep their body concealed in a crevice, with the only visible part being its array of arms.

On the underside of the body are about twenty claw-like appendages known as cirri which are used to cling on to the underlying surface, but they are lost in older specimens, which attach directly using the underarms.