Phylum: Echinodermata
Class: Edrioasteroidea
Family: Isorophidae (Bell, 1974)
Cincinnatian Genus: Isorophus

Geologic Range
Middle Ordovician to Pennsylvanian

Common Paleoecology
Isorophidae is an extinct family of stationary low-level epifaunal suspension feeders

Description of the Family

  • Theca domed
  • 4 primary orals
  • Ambulacral coverplates forming alternatint multiple biseries
  • Most small to moderate size, being 10-20 mm in diameter

Published Descriptions

Bell (1974):

  • Domal theca; oral area including four primary orals, two pairs of laterally shared coverplates, one large hydropore oral, and secondary orals; hydropore structure having few plates, integrated with central oral rise; ambulacral coverplates forming alternating multiple biseries; interambulacrals squamose and imbricate.
  • Most Isorophidae are small to moderate-sized edrioasteroids, 10 to 20 mm being common adult diameters.