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sea
stars text index | photo
index
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| Phylum Echinodermata > Class Stelleroida > Subclass Asteroidea |
| Eight-armed
sea star Luidia maculata Family Luidiidae updated Apr 09 Where seen? This elegant and active sea star is sometimes seen on our Northern shores, on soft, silty shores, near seagrass meadows and coral rubble. It is usually seen alone, and not in large groups. It moves rapidly and is usually more active at night. Features: Diameter with arms to 12-20cm. Those seen usually with eight arms, although according to Gosliner, it may have 7 to 9 arms. The arms are long, somewhat rounded in cross-section, and tapered to a sharp tip, edged with small sharp spines along the sides. The upper surface of the body is covered with special flat-topped, pillar-like structures called paxillae. The underside is pale, and from grooves along the arms emerge large tube feet with club-like, pointed tips. Colours and patterns on the upperside are highly variable in shades of greyish blue, to brown and beige, but usually with a darker star-shaped pattern in the centre, and dark irregular bars along the length of the arms. Sometimes mistaken for the Common sea star (Archaster typicus). While most Common sea stars have five arms (although some may have six), these have large tube feet with sucker-shaped tips. The Eight-armed sand star has, well, eight arms and large tube feet with pointed tips. What does it eat? According to Lane, it burrows in soft sediments and feeds on small buried animals such as molluscs and other echinoderms. Coleman has a photo of this sea star eating another sea star! Status and threats: According to Lane, the Eight-armed sand star used to be common on our mainland shores. It is now listed as 'Endangered' on the Red List of threatened animals in Singapore. It was formerly found near the mainland prior to reclamation but recently known only from the Pulau Ubin and Pulau Tekong area in low numbers. |
 A huge one bigger than my foot! Pulau Sekudu, Apr 06   This one has lost one arm. |
 Pointed tube feet. |
 Small sharp spines along the edge of the arms. |
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 Flat-topped, pillar-like structures called paxillae. |
 Close up of the mouth. |
 Underside. |
Eight-armed sea stars on Singapore shores
 Chek Jawa, Jul 07 |
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 Underside. |
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 Pointed tube feet. |
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Links
References
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Times Edition, Singapore. 144 pp.|
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