The Echinoid Directory

Unibothriocidaris Kier, 1982, p. 310

Diagnostic Features	Test small (ca. 10 mm); shape unknown, presumed globular; plating thick and tesselate, not imbricate. Composed of multiple columns of hexagonal ambulacral plates arranged in rows forming chevra. A single radial column of hexagonal-shaped imperforate plates separates zones of perforate ambulacral plates and are interpreted as perradial. Perforate ambulacral plates with a single large pore surrounded by a raised peripodial rim. There may be remnants of a dividing partition visible, especially internally. A perforate tubercle occurs in contact with each peripodial rim. Small granules cover the remainder of the plate. Peristome, apical disc, spines and lantern all unknown.
Distribution	Upper Ordovician (Caradoc), North America.
Name gender	feminine
Type	Unibothriocidaris bromidensis Kier, 1982, p. 311, by original designation.
Species Included	U. bromidensis Kier, 1982; Upper Ordovician (Bromide Formation), USA. U. kieri Guensburg, 1984; Upper Ordovician (Caradoc), USA.
Classification and/or Status	Stem group Echinoidea; Bothriocidaridae. Monophyletic.
Remarks	Both Neobothriocidaris and Bothriocidaris have double rather than single pores in each plate. Furthermore Bothriocidaris has only two columns of perforate plates in each zone and in Neobothriocidaris the peripodial rim is shared between two adjacent plates rather than being confined to the centre of a single plate as it is in Bothriocidaris and Unibothriocidaris. Kier, P. M. 1982. Echinoids. Pp. 310-314 in J. Sprinkle (ed.) Echinoderm Faunas from the Bromide Formation (Middle Ordovician) of Oklahoma. Univeristy of Kansas Paleontological Contributions Monograph 1. Guensburg, T. E. 1984. Echinodermata from the Middle Ordovician Lebanon Limestone, Central Tennessee. Bulletins of American Paleontology, 86, 1-100.