Size of the fossilized sea urchins approx. 7 - 9 cm
Origin: Madagascar
Phylum: Echinoderms (Echinodermata)
Class: Sea urchins (Echinoidea)
Order: Sand dollars
In contrast to "real" sea urchins, sand dollars, which belong to the irregular sea urchins (Irregularia), have no spines. However, they fascinate the observer and collector with their perfect fivefold division. The animals are very flat and have a skeleton composed of small calcareous plates covered by thin tissue and many cilia. With the help of these small hairs, which are constantly in motion, the plankton in the sea is waved over the body up to the mouth opening of the sand dollar. In the mouth opening sits a five-pointed structure covered with regrowing teeth, the so-called "lantern of Aristotle". The individual elements of this jaw apparatus can be moved against each other to shred the sand dollar's food. As the Greek scholar Aristotle (384 BC to 322 BC) was the first to describe this anatomical feature of these fossils, they now bear his name in his honor.
Like many other echinoderms, sand dollars can move forward slowly with the help of their ambulacral system. This system consists of several channels inside the animals that are filled with a fluid. The channels end in small tentacle-like feet. These little feet stretch forward in the desired direction of movement, then attach themselves to the substrate and then shorten again. This shortening then pulls the entire body of the animal backwards.
The name "sand dollar" is derived from the flat shape and color of the animals, which is reminiscent of a coin. In some Spanish-speaking countries, sand dollar fossils are also called "galleta de mar", i.e. "sea cookie".
GPSR
| Manufacturer | Marco Schreier Mineralienhandlung GmbH, Im Osterholz 1, 71636 Ludwigsburg, Germany, www.marcoschreier.com Contact |
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Minerals and gemstones for collecting and gifts: Sand dollar (sea urchin), 08 - 09cm
Hello! My name is Marco Schreier, founder of the Mineralienhandlung GmbH of the same name, a specialist wholesaler for minerals, fossils, gemstones, tumbled stones, collector's objects and gift items made of stone. In the year 1998 I founded the brand Maulwurf Geschenke aus der Natur® in order to combine our product range for resellers, museum shops, dealers and other commercial users of the precious stones with our quality guarantee.
You will only receive mineralogically correctly identified stones from us, which promote the joy of collecting and experiencing the precious treasures of nature. Treatments such as coatings or coloring are always declared. Our own production in Asia guarantees the best quality at attractive wholesale prices and fair and transparent product procurement. I personally vouch for this.