Nice, I picked-up a Trilobite from Russia a few years ago. It's interesting to have a critter that roamed the Earth 488,000,000 years ago...
Very Clean!!
For the geeks out there, some information on my specimen.
Trilobites are extinct arthropods in the class Trilobita. Asaphus kowalewskii is one of the 35 species of the genus Asaphus (sometimes called Neoasaphus) of the class Trilobita. During the Ordovician period, several species of the genus Asaphus developed remarkable adaptations to changes in turbidity, with Asaphus kowalewskii presumably arising in a time of increased turbidity. The trilobite may have lain in wait buried in a benthic layer of loose debris or sediment with only its periscope eyestalks protruding above, looking out for danger or prey.
The Ordovician period is the second of the six periods of the Paleozoic era about 488 million years ago. The Ordovician was a time of shallow continental seas rich in life. The first coral reefs appear, trilobites and brachiopods in particular were rich and diverse. Sea levels were high, marine ingressions worldwide were the greatest that has ever been experienced. During the Ordovician period, the southern continents were collected into a single continent called Gondwana. Gondwana started the period in equatorial latitudes and, as the period progressed, drifted toward the South Pole. The early Ordovician period was thought to be quite warm, at least in the tropics. Shallow clear waters over continental shelves encouraged the growth of organisms that deposit calcium carbonates in their shells and hard parts. By the end of the period, Gondwana had neared or approached the pole and was largely glaciated.
The Ordovician period came to a close in a series of extinction events that, taken together, comprise the second largest extinction event in Earth's history in terms of percentage of genera that went extinct. The extinctions occurred approximately 444 million years ago and mark the boundary between the Ordovician period and the following Silurian Period. The most commonly accepted theory is that these events were triggered by the onset of a long ice age, perhaps the most severe glacial age of the Phanerozoic, in the Hirnantian faunal stage that ended the long, stable greenhouse conditions typical of the Ordovician period.
At that time all complex multicellular organisms lived in the sea, and about 49% of genera of fauna disappeared forever; brachiopods and bryozoans were decimated, along with many of the trilobite, conodont and graptolite families. The last of the trilobites disappeared in the mass extinction at the end of the Permian period 250 million years ago.
Class: Trilobita
Order: Asaphida
Suborder: Asaphina
Superfamily: Asaphoidea
Family: Asaphidae
Genera: Asaphus (aka Neoasaphus)
Species: Asaphus kowalewskii
This specimen was found in the Middle Ordovician Asery Level deposit of the Vilpovitsy Quarry near Saint Petersburg, Russia. During the Ordovician period, what is now Eastern Europe was a shallow inland sea.
mrgreen: mines like that)
