©Lyle Vail: Himerometra robustipinna at Lizard Island. Dark maroon, sometimes with grey, is the common colour form.
©Anne Hoggett: The less common colour morph of Himerometra robustipinna at about 20 m depth at Lizard Island.
Colours
Distinguishing features
A middling-to-large crinoid that is always fully exposed, with up to about 60 arms and a good ring of stout cirri. This is one of the most conspicuous crinoids at Lizard Island.
There are two colour forms. The most common is all or mostly maroon. Some of these have grey/brown/yellow/orange brachials and the maroon pinnules may have yellowish tips.
The less common form lacks any red/maroon colour. It often has a dark/pale "block" pattern but if that is absent, the brachials are black or grey and the pinnules are black with white or yellow tips. This was considered a separate species (Himerometra magnipinna) until Taylor et al (2017) found no genetic evidence to support it.
Size
- Up to 35 cm (diameter)
Depth range
- Depth range data is not yet available.
Synonyms
Distribution
©Atlas of Living Australia: Australian distribution
Distribution and habitat preferences
Himerometra robustipinna usually perches on living hard coral in areas of moderate to high water movement. They are often found in aggregations.
This species is very common at sites with strong current flow such as North Point, the lagoon entrance and the reef slope between Bird and South Islands.
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.
- Taylor, K.H., G.W. Rouse and C.G. Messing (2017). Systematics of Himerometra (Echinodermata: Crinoidea: Himerometridae) based on morphology and molecular data, Zoological Journal of the Linnean Society, 181: 342-356. LIRS catalog number 10099.
Other references
- Lanterbecq, D., G.W. Rouse and I. Eeckhaut (2009). Evidence for cospeciation events in the host-symbiont system involving crinoids (Echinodermata) and their obligate associates, the myzostomids (Myzostomida, Annelida), Molecular Phylogenetics and Evolution, doi: 10.1016: jymev20090811. LIRS catalog number 1274.
- View all references