species: Dorometra nana in Lizard Island area: all known taxa (Lizard Island Field Guide)
Dorometra nana


©Anne Hoggett: Dorometra nana at North Point, Lizard Island, from under rubble.

©Anne Hoggett: Dorometra nana at North Point, Lizard Island, from under rubble.

©Anne Hoggett: Dorometra nana at North Point, Lizard Island, from under rubble.
Kingdom Animalia
Phylum Echinodermata
Class Crinoidea
Order Comatulida
Family Antedonidae
Genus Dorometra
Species Dorometra nana

Colours

                                       

Distinguishing features

Antedonids are small crinoids with ten very flexible arms up to about 60 mm long, usually found under slabs of rubble. Only two species are known from Lizard Island, Dorometra parvicirra and Dorometra nana.

Dorometra is distinguished from other antedonid genera by having cirrus segments that are flared at their distal ends, overlapping the next segment. Both species of Dorometra known from the Lizard Island area have about 40 delicate cirri. They are distinguished from each other by the relative sizes of the oral pinnules. In Dorometra nana, the first two pinnules on the outer side of each arm are about the same length and the third is much longer. This character is not useful in the field because it needs microscopic examination.

Size

  • Up to 6 cm (Arm length)
  • Up to 6 cm (Arm length)

Depth range

  • Depth range data is not yet available.

Synonyms

Similar taxa

Comments

Arm number, size, habitat, posture, and cirri indicate Dorometra but proximal pinnules are not visible in the photo to distinguish the species.

by Anne Hoggett

Distribution


©Atlas of Living Australia: Australian distribution

Distribution and habitat preferences

Always fully concealed. Messing (2006) records both species of Dorometra as part of an unusual soft-bottom fauna in 12 to 17 m depth off Osprey Island.

Web resources

References

References that assist with identification

  • Clark, A.M. and F.W.E. Rowe (1971). Monograph of shallow-water Indo-west Pacific echinoderms British Museum (Natural History), London.

Other references

  • Messing, C.G., D.L. Meyer, U.E. Siebeck, L.S. Jermiin, D.I. Vaney and G.W. Rouse (2006). A modern soft-bottom, shallow-water crinoid fauna (Echinodermata) from the Great Barrier Reef, Australia, Coral Reefs, 25: 164-168. LIRS catalog number 956.