Purchased from Youngblood
Estate by the University of Oklahoma for display at the Youngblood
- Echinodermata: marine animal
Location: Holzmaden, Baden-Württemberg,
Germany (S. E. of Stuttgart).
Geologic Period Range:
Ordovician to present. Traditionally estimated at 500 million years Before
Common Era (BCE) to present.1
Age of Specimen: Lower
Jurassic Period. Estimated from 172 to 180 million years BCE.1
of the class crinoidea are in the phylum Echinodermata, which includes such
radially symmetrical marine animals as sea urchins, starfish, and brittle
stars. Crinoids are popularly called "sea lilies" due to their body's
bulbous lily-like shape. These marine, invertebrate animals are found still
living today, generally as individuals. They are usually bound to the sea
floor by a stalk opposite their mouth, and appear in a variety of beautiful
colors, thereby presenting a flower-like appearance. Crinoid fossils are
sometimes golden-hued from absorption of iron pyrites ('"fools gold"), as in
this specimen, thereby giving the appearance of a golden lily.
This Crinoid is of the
species Seirocrinus subangularis, and it is of the family Pentacrinitidae.
It is characterized by a globular body enclosed by a small calyx, from which
freely moving "arms" extended upward to gather the marine animal's food. At
the bottom of the jointed, flexible stem, but missing from this specimen,
was a "root-like structure" by which it was attached to the sea bottom or
sea floor plant material, and, occasionally, to driftwood. Specimens of
this species have very long stems, tapering toward the top, up to 65 feet
(18 meters) in length.
This 3 1/2 foot (1-meter)
single-calyx crinoid is very well-preserved in a smooth, dark matrix
consisting of fine-grained silts and clays which eventually formed
bituminous (pitch-like) Poisidonia Shale, providing contrast to the
golden-hued calyx-protected globular body. Some of the shale around the
specimen has been removed in order to better display the crinoid, The shale
matrix also contains small pelecypoda (clams) and Posidonia bronni. This
specimen was quarried in an area of Germany containing a large concentrated
volume of crinoids with exceptional preservation, most likely suggesting a
rapid burial, probably by catastrophic mud deposition, perhaps triggered by
one or more tectonic events.
Estimated by traditional Uniformitarian concepts (gradual, uniform changes
over great periods of time, similar to the rates of change observed today).
To compare, return to:
Crinoids on page 4.
Fossils - O.U. thumbnails and links to
Library fossils on page 3.
"Prize" Ammonite - O.U. on
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