Tuesday, April 29, 2014

Cyrtospirifer sp. brachiopod from Lindley, NY

Sometimes collecting sites are ephemeral, exposed for a short time and then gone. A series of roadcuts were being excavated near the NY/PA border into the Wiscoy Fm., (upper Devonian, Fransian stage, equivalent to Lockhaven Fm. in PA) and the rubble was used as road ballast. While the rocks were exposed I managed to do some exploring of them and found this intact fossil of Cyrtospirifer whitneyi.

Brachial valve
Pedicle valve

Based on similar fossils pictured in the "Devonian Plates" book by the Maryland Geological Survey, 1913, Plate LVI, I'm going to call this Cyrtospirifer disjunctus.

Edit (04/29/2014) - I wrote this post originally in December of 2013 and since then have consulted the "Index of North American Fossils" which states that Cyrtospirifer disjunctus is "a loosely drawn species and the name probably should not be used for many post-Chemung types now placed here" (pg. 321). As the Wiscoy formation is considered part of the Chemung fauna C. disjunctus could properly be used here but a comparison to C. whitneyi from Iowa shows a closer resemblance both within the book (plate 121 - 53 to 55) and with a specimen I posted earlier.

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