|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Asteroidea - Valvatida - Ophidiasteridae
If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
|D. B. Blake and R. Reid 1998||Differentiated by ossicles of primary series in well-defined longitudinal rows; ossicular sizes regularly gradational with no scattered enlarged primary ossicles. Adambulacral furrow spines elongate, granular covering layer lacking. Interbrachial marginals not slightly enlarged; enlarged marginal granule depressions present; intermarginal series present but not disrupting alignment of marginals. Ophidiasterid close to those of Ferdinia-group sensu Marsh and Campbell (1991). Arms, disk are somewhat flattened (rather than columnar), a shape suggestive of that of goniasterids. Arm tips, marginal, abactinal series clearly differentiated. Carinal row well-defined, nearly continuous except some smaller ossicles intercalated; one lateral row on each side of carinal series. Marginals larger than abactinals, actinals; marginal rows without intercalated small ossicles; inferomarginals larger proximally but ossicles of two series becoming approximately equal in size distally. Well-defined intermarginal series present proximally. Ventral interbrachial area large, with multiple ossicular rows. Furrow spines columnar, elongate, attenuated, six to height in palmate arrangement on each ossicle; subambulacral spines about three, larger than those of furrow series, flattened; covering granular layer lacking.|