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echinoderms text index | photo index
Phylum Echinodermata > Class Echinodea > sand dollar
Photo index of echinoids on Singapore shores 
sand dollars

Size given is the diameter of the body without the spines.

Keyhole sand dollar
Echinodiscus sp.

Cake sand dollar
Arachnoides placenta

Thick-edged sand dollar
Jacksonaster depressum

Pink sand dollar
Peronella lesueuri
About 10cm. A pair of slots in the body margin. Flower-like petalloid obvious even in living specimens. Usually alone in sandy areas near seagrasses. Sometimes seen on our Northern shores. 2-8cm. No holes in the body, star-shaped petalloid not obvious in living specimens. In large groups in sandy areas near seagrasses. Seen on many of our sandy shores in the north and south. 4-6cm. Rather pentagonal, thick at the edges and at the centre. Petalloid obvious. Longer spines at the edges of the body. Pale rose pink or grey. Silty sand near reefs. Sometimes seen on some of our shores. 6-8cm. Circular. Petalloid obvious. Bright pink. In sandy lagoon. Sometimes seen at Pulau Sekudu and Changi.  

photo index of
echinoderms on this site
Phylum Echinodermata
all echinoderms

With arms

  many, feathery
feather stars

five, bristley
brittle stars

sea stars
small <10cm
large >10cm

  flat, coin-like
sand dollars

spherical, spiny
sea urchins
heart urchins


  sea cucumbers
short <10cm
long >10cm
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