Name: Inaudinata; Cladida; Cyathocrinites iowensis, Platycrinites saffordi
Age: Lower Mississippian Osagean Stage
Size (25.4 mm = 1 inch): Crinoid: Cyathocrinites Crown 45 mm long by 30 mm wide Platycrintes Stem: 98 mm long Matrix: 130 mm by 130 mm
Location: Crawfordsville, Indiana
 Description:
A fine example of an advanced Inadunate Cladid crinoid of the Family
Cyathocrinidae, this is  Cyathocrinites
iowensis. The elegantly helical stem is diagnostic of the member of
the Platycrinitidae known as Platycrinites saffordi. The stem of a
crinoid served two main functions: placing the crown into the water
column to filter out food particles, and anchoring the crinoid in
the substrate. The fingerlike structures projecting from the stem
are the radicular cirri which show this crinoid favored a muddy bottom.
These crinoids must have been rapidly buried to be preserved in such
a fine state of preservation. They are very esthetically displayed
on this pentagonal siltstone matrix block. |
