The first gomphothere from the Eastover Formation

GomphotheriumIn 2010, Rose Schooff and Christie Aldridge-Nunn donated to VMNH a tooth fragment collected from Rose’s property in New Kent County, Virginia, which I wrote about at the time. Brian Beatty and I finally got around to writing a report on this interesting specimen, which has been published online as Jeffersoniana 29 (pdf).

The tooth (above) is a fragment of an upper left deciduous premolar from a gomphothere, an elephant-like proboscidean like the one below (from the Nebraska State Museum):

2013-03-14bThis fragment is pretty typical for gomphothere remains. They are already known from various locations on the Atlantic Coastal Plain, including the upper Calvert Formation in Maryland and Virginia (~14 million years), the Choptank Formation in Maryland (~13 million years), and the Yorktown Formation in North Carolina (~4.5 million years). So why publish this one?

Rose and Christie collected this specimen from a shell bed that included Chesapecten middlesexensis and Isognomen sp., which means this tooth came from the Late Miocene Eastover Formation (~7 million years). This is the first gomphothere tooth ever reported from the Eastover, and in fact appears to be the first land mammal of any kind from that formation. It wasn’t entirely surprising that gomphotheres were living along the Atlantic coast 7 million years ago; after all, we already knew they were here at 13 million and at 4.5 million years. Even so, it’s nice to get confirmation in the form of an actual specimen.

There are essentially no terrestrial deposits in Virginia between the Triassic/Early Jurassic and the Pleistocene. That means that our only record of terrestrial life in Virginia over a span of more than 200 million years are plants and animals like this one that washed out to sea and were preserved in marine deposits, so even fragmentary records provide valuable data. In fact, to find another gomphothere record the same age as the New Kent County specimen you have to go 500 kilometers west, all the way to Gray Fossil Site in Tennessee.

Thanks again to Rose and Christie for donating this specimen. Jeffersoniana 29 is currently available as a free pdf download.

Reference:

Beatty, B. L. and A. C. Dooley, Jr. 2013. The first terrestrial mammal from the Late Miocene Eastover Formation of Virginia. Jeffersoniana 29:1-6.

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