By using this approach, members of the Bmp, TGF-beta, and Hox gene families were found to be associated with arm regeneration in the crinoids
Antedon bifida and Antedon mediterranea (Thorndyke et al.
The shale also contains bryozoans, orthoconic cephalopods, rare crinoids
Such rapid regeneration has also been reported for the disk of other brittlestars (Dobson, 1988) and for the intestine of the crinoid
Antedon mediterranea (Mozzi et al.
These larvae subsequently develop into nonfeeding doliolaria larvae, resembling the larvae of most crinoids
This conclusion is also supported by the sedimentologic data, wich show a greater content of filaments (more typical in Callovian deposits) in the lower interval, and a greater content in sponge spicules and crinoid
bioclasts in the upper interval (cfr.
Studies of modern crinoids
have shown that biotic interactions are common in crinoid
populations and involve a diverse suite of macro- and microorganisms (e.
The specimens studied come from a packstone bed cropping out near the waterline of the Serga River, with a high content (60%) of crinoid
If their crinoid
ancestors spent their entire adult lives similarly anchored to one spot, they could not have spread worldwide without help.
Although most crinoid
fossils are from "spindly, plant-like animals anchored to sea floor rocks," the 1 to 4 millimeter star-shaped parts of these crinoids
that the scientists dug up were used to grab and hold onto objects but were not found attached to anything.
Inspect them closely and you may make out the curve of a gastropod, the cone-shaped shell of a cephalopod, or a disc or rod-like structure that was once a piece of a crinoid
Morgan presents a guide for students and researchers in invertebrate paleontology and for collectors to the more than 60 valid species that encompass at least 40 genera and represent all the major crinoid
groups of Mississippian Age: both primitive and advanced cladids, camerates, flexibles, and disparids.
Biochemical and energetic composition of bathyal achinoids and an asteroid, holothuroid and crinoid
from the Bahamas.