Animal Profiles
Sea urchins

Sand Dollar

Clypeasteroida

Living

Living individuals or members of this group exist today. This does not mean they are safe from extinction.

Sand dollars are flattened relatives of sea urchins. This account describes the Pacific sand dollar (Dendraster excentricus), which forms beds on sandy coastal seabeds.

Dendraster excentricus, the representative described in this account.

Dendraster excentricus, the representative described in this account.

louisiv826 · CC BY

At a glance

Location
Pacific sand dollars occupy nearshore sand along western North America.
Habitat
Coast
Diet
Filter feeder
Food
Tube feet, spines and cilia help collect and move small food particles towards the mouth.

Classification

Common name
Sand Dollar
Browse group
Sea urchins
Scientific name or taxon
Clypeasteroida
Taxon rank
order
Order
Clypeasteroida
Source classification
Echinoidea

Taxonomy checked against GBIF. For breeds and hybrids, this describes the listed parent taxon.

Three things to know

  • It is related to sea urchins.
  • Living animals have fine spines.
  • Currents carry suspended food past it.

Habitat and range

Pacific sand dollars occupy nearshore sand along western North America. Moderate water movement carries food through beds that may contain many closely spaced animals.

Appearance and adaptations

Living animals carry fine movable spines over a flattened skeleton called a test. Their dark or purplish surface looks different from the pale, bare tests found after death.

Diet and behaviour

Tube feet, spines and cilia help collect and move small food particles towards the mouth. Animals may stand partly upright in the sand to intercept passing currents.

Sources

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