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Diagnostic Features
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- Apical disc dicyclic.
- Ambulacral plating trigeminate, with pore-pairs in oblique arcs of three forming a continuous adradial band.
- Ambulacral plates with primary tubercle only on every second or third plate.
- Pore-zones forming relatively broad and uniformly wide bands from apex to peristome.
- Interambulacral plates with central primary tubercle not strongly differentiated from secondaries; secondary tubercles relatively common.
- Globiferous pedicellariae with tubular blade and paired lateral teeth.
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Distribution
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Late Miocene to Recent, Atlantic, Mediterranean, Subantarctic |
| Name gender |
masculine |
| Type |
Echinus esculentus Linnaeus 1758, p. 663, by subsequent designation of Fell & Pawson, 1966, p. 431. |
| Species Included |
- E. esculentus Linnaeus, 1758; Recent, N. Atlantic.
- E. tenuispinus Norman 1868; Recent.
- E. acutus (Lamarck, 1816); Recent, Atlantic.
- E. anchistus Clark, 1912; Recent, Chile.
- E. gilchristi Bell, 1904; Recent, South Africa.
- E. multidentatus Clark, 1925; Recent, Kermadec Islands.
- E. melo Lamarck, 1816; Recent, Atlantic and Mediterranean.
- E. stenoporus (Mortensen, 1942); Recent, S. Africa.
- E. wallisi Agassiz, 1880; Recent, West Atlantic.
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| Classification and/or Status |
Camarodonta; Echinoida; Echinidae.
Probably monophyletic.
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| Remarks |
Mortensen (1926) included in Echinus forms with both primary tubercles on every ambulacral plate, and those with primary tubercles on every second or third compound plate. However, Fell & Pawson (1966) erected a new genus Gracilechinus, for species in which a primary ambulacral tubercle occurs on each plate. Psammechinus differs in being altogether more densely tuberculated and Parechinus is distinguished by its three clearly discrete vertical columns of pore-pairs. Stirechinus has a vertical ridge connecting primary interambulacral tubercles. Finally, Stirechinus and Dermechinus both have much more strongly granular plating. From a palaeontological point of view, the distinction of Echinus from a number of other genera is difficult.
Mortensen, T. 1943. A monograph of the Echinoidea Part III, 3. Camarodonta II. C. A. Retzel, Copenhagen.
Fell, H. B. & Pawson, D. L. 1966. Echinacea. In R. C. Moore (ed.) A Treatise on Invertebrate Paleontology. Part U Echinodermata 3. Asterozoa-Echinozoa. University of Kansas Press and the Geological Society of America, Boulder.
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