[=Eucosmechinus Lambert & Thiery, 1814, p. 270 (objective)]
Diagnostic Features |
|
---|---|
Distribution | Upper Jurassic (Oxfordian-Tithonian) to Lower Cretaceous (Valanginian), Europe, North Africa |
Name gender | masculine |
Type | Eucosmus decoratus Agassiz, in Agassiz & Desor, 1847, p. 356, by original designation. |
Species Included |
|
Classification and/or Status | Euechinoidea, Echinacea, Arbacioida Presumed monophyletic. |
Remarks | Distinguished from the very similar Magnosia tby having only a double column of tubercles in each ambulacral zone rather than four or more. In E. meslei the ambulacra are so narrow that there are only two columns of ambulacral tubercles which dominate the interporal zone, often alternating. Ambulacral plates are all simple, unlike Codiopsis where two of the three plates in each triad are demiplates. The low, wide plates indicate affinities with the type species of Magnosia rather than with earlier species. Agassiz, L. & Desor, P. J. E. 1846-1847. Catalogue raisonné des familles, des genres, et des espèces de la classe des échinodermes. Annales des Sciences Naturelles, Troisième Série, Zoologie : 6 (1846): 305-374, pls. 15-16; 7 (1847): 129-168; 8 (1847): 5-35, 355-380. Mortensen, T. 1935. A monograph of the Echinoidea II. Bothriocidaroida, Melonechinoida, Lepidocentroida and Stirodonta. C. A. Reitzel, Copenhagen |