Diadema (sea urchin)
Diadema is a genus of sea urchins of the family Diadematidae.[1]
| Diadema | |
|---|---|
 | |
| Diadema setosum | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Echinodermata |
| Class: | Echinoidea |
| Order: | Diadematoida |
| Family: | Diadematidae |
| Genus: | Diadema Gray, 1825[1] |
| Species | |
| |
Characteristics
It is one of the most abundant, widespread, and ecologically important shallow water genera of tropical sea urchins. It is found in all tropical oceans, although is ubiquitous in the Indo-Pacific region, where it inhabits depths down to 70 m. However each species inhabits roughly separate areas of ocean.
Speciation within the genus can be difficult to confirm, partly due to hybridisation, which is at least known to occur between Diadema savignyi and Diadema setosum.
The species vary in types of sea bed they inhabit, with Diadema savignyi inhabiting sandy beds and back reef where damaged; while Diadema setosum can also commonly be found among seagrass.
Fossil record
The fossil record of Diadema is extremely poor, consisting only of spines that possibly belong to the genus, some of which go back to the Miocene, 5 to 25 million years ago.
Species list
According to World Register of Marine Species :
| Image | Scientific name | Distribution |
|---|---|---|
 | Diadema africanum (Rodríguez, Hernández, Clemente & Coppard, 2013) | Western Africa |
 | Diadema antillarum (Philippi, 1845) | Gulf of Mexico |
| Diadema ascensionis (Mortensen, 1909) | Central tropical Atlantic | |
 | Diadema mexicanum (Agassiz, 1863) | West coast of tropical Americas |
| Diadema palmeri (Baker, 1967) | South-west Pacific, especially New Zealand | |
 | Diadema paucispinum (Agassiz, 1863) | Central Pacific, and possibly North Indian Ocean and other zones |
 | Diadema savignyi (Michelin, 1845) | Tropical Indo-Pacific |
.JPG.webp) | Diadema setosum (Leske, 1778) | Tropical Indo-Pacific |
References
- Kroh, A., Mooi, R. (2018). Kroh A, Mooi R (eds.). "Diadema Gray, 1825". World Echinoidea Database. World Register of Marine Species. Retrieved 8 November 2018.
Bibliography
- Nyawira A. Muthiga and Timothy R. McClanahan, "Diadema", in John M. Lawrence, Sea Urchins: Biology and Ecology, London, Elsevier, 2013.
- Lessios, H. A.; B. D. Kessing; John S. Pearse (2001). "Population structure and speciation in tropical seas. Global phylogeography of the sea urchin Diadema". Evolution. 55 (5): 955–975. doi:10.1554/0014-3820(2001)055[0955:PSASIT]2.0.CO;2. PMID 11430656. Archived from the original on 5 January 2013.
- Edge of reef