Glyptocrinidae

Classification
Phylum:Echinodermata
Class: Crinoidea
Order: Monobathrida
Family: Glyptocrinidae (Zittel, 1879)
Cincinnatian Genus: Glyptocrinus, Pycnocrinus

Geologic Range
Middle Ordovician – Late Silurian

Common Paleoecology
Glyptocrinidae is an extinct family of stationary upper-level epifaunal suspension feeders

Description of the Family

  • Conical to subglobose calyx
  • Calyx plates with stellate ornamentation
  • Five basal plates
  • Fixed secundibrachs approximately 2-8+ per ray
  • Tegmen composed of many small plates
  • Column cylindrical
  • Axial canal pentagonal

Published Descriptions

Treatise on Invertebrate Paleontology, Part T, Vol. 2(2) (1978):

  • (Same as Superfamily) Calyx conical to subglobose, plates generally with stellate ornamentation; basals five; fixed secundibrachs two to eight or even more in each ray; fixed tertibrachs present in some species; interprimibrachs numerous and well defined; intersecundibrachs numerous, less definite; primanal followed by three plates in next row above; median anal ridge present. Tegman composed of many small plates/ anus opening directly through it. Rays ordinarily not branching beyond tertibrach series; brachials uniserial or biserial. Column cylindrical; axial canal pentagonal.

Glyptocrinus


Pycnocrinus