Saccocoma tenella (4)

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Echinoderma (sea-urchins, star-fishes, crinoids)

Crinozoa (crinoids)

Product code: F17458
Available: Yes

Provenience: Germany (Solnhofen, Bavaria)
Geological Era: Late Jurassic (Tithonian)
Age: 150 million of years
Measure: cm 9.2 x 8.5

Price: 36,97 $

Unique Article

Description

fossil crinoid, diameter cm 4, slab cm 9.2 x 8.5.

Saccocoma (feather stars) is a genus of extinct crinoids that lived from Upper Jurassic to Lower Cretaceous in Europe and North America. Currently only four species are known. Only the species Saccocoma tenella (Goldfuss, 1831), found in Solnhofen in Bavaria is known from complete remains. With the exception of the limestone of Solnhofen, where the samples are often perfectly preserved intact, usually only found isolated elements exoskeleton, obtained and analyzed with micropaleontological methods. This small natant crinoids had a total diameter (including arms) up to about 5 cm. The body is the size of a pea, and shows the typical pentaradiate symmetry of higher echinoderms. From the body depart five pairs of thin feathery arms forking very soon, so that Saccocoma apparently seems to have ten arms. The mouth is located on the ventral side of the body. The animal is assumed could only swim using ciliated parts of the arms, as these are probably too rigid to allow real movements, and were mainly used to filter food from the water towards the mouth. The natant crinoids were often preyed from Ammonites, as shown by coprolites (fossil feces) of these cephalopods.
During the Middle Ages, when the crinoids were not yet known, it was believed that the fossils found at Solnhofen were evil traces and again interpreted as a legacy of the Biblical Flood. In 1616 the botanist Basil Besler (1561-1629) speculated that the Solnhofen Saccocoma crinoids were fossil spiders, while the doctor Johann Jakob Baier (1677-1735) interpreted for the first time these fossils like starfish.