December 12, 2012 23:06
An international team of scientists examined the unique discovery, made in the English county of Herefordshire. Among the fossil Silurian rocks they discovered previously unknown creature similar to the crustaceans.
Surprisingly, the tiny arthropods age 425 million years ago have survived not only the outer shell fossils, but also the soft tissues, including the eyes, gills and digestive system. The study is described in an article in the journal Proceedings of The Royal Society B.
Two representatives of the class of ostracods, which are the ancestors of modern crabs, lobsters and crabs are trapped in volcanic ash at a time when the south of present-day England lapping sea.
Ostracods are the most common fossil arthropods. Their hard covers, which are a bivalve shell, found in many deposits. But the first time researchers were able to get acquainted with the internal structure of such ancient creatures.
Using sophisticated technology, biologists have divided each detected sample size of one centimeter to 500 layers with thickness of 20 micrometers. Then each piece was photographed, and they were used to create a computer model.
Detailed study of accurately determine the location of a new genus in the evolutionary tree of invertebrates. It turned out that before these creatures known only on the balance of the shell, are of an entirely different taxonomic group.
"This is a very important discovery, because we can refer to these animals to a group on the basis of biology, not by a shell-shaped — said lead study author David Sayveter (David Siveter) from the University of Leicester. — Our research shows that one should be careful when classifying fossil ostracods exclusively on the characteristics of the shell. "
The new species was named Pauline avibella. The first word (the genus name) was used in the memory of the late wife Pauline Sayvetera, second (avibella) means "beautiful bird", which points to the similarity of the shell with the bird wing.