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''Fedexia'' is an extinct genus of carnivorous temnospondyl within the family Trematopidae. It lived 300 million years ago during the late Carboniferous period. It is estimated to have been two feet long, and likely resembled a salamander.〔(Pitt student finds fossil of ancient amphibian ), Pittsburgh Post-Gazette, March 15, 2010〕 ''Fedexia'' is known from a single skull found in Pittsburgh, Pennsylvania. It is named after the shipping service FedEx, which owned the land where the holotype specimen was first found. ==Discovery== The holotype skull (CM 76867) was discovered on land owned by the FedEx Corporation near Pittsburgh International Airport in 2004. Adam Striegel, a student at the University of Pittsburgh, found the skull on a field trip to the area, but he mistook the teeth for a fern frond. It was later recognized as a skull by class lecturer Charles Jones, and was taken to the Carnegie Museum of Natural History for further study. The specific name of the type species honors Adam Striegel.〔 The area where the holotype was discovered was part of the Casselman Formation of the Conemaugh Group. In North American Carboniferous stratigraphy, these strata are early Virgilian in age. According to ICS standards, they are Gzhelian in age. The skull itself was found lying near the base of a road cut that exposes the lower part of the Casselman Formation. The Casselman Formation overlies the Ames Limestone, which represents the last marine submergence of the Appalachian Basin. The earliest portions of the Casselman Formation, consisting of sandstones and siltstones, are overbank levee deposits that were formed at the shoreline of the retreating Ames Sea. Overlying these deposits is the Grafton Sandstone, a cross-bedded channel-phase sandstone deposited by a meandering river. Above the sandstone lies the Birmingham Shale, which includes fine-grained siltstone and shale overbank deposits. A thick paleosol is present at the top of the Birmingham Shale, and it is capped by limestone that is of freshwater lacustrine (lake) origin.〔 The holotype skull likely came from the limestone that caps the Birmingham Shale or the underlying paleosol. Because it was not found ''in situ'', the horizon in which the skull originated cannot be determined definitively. The gray limestone matrix that is found inside the skull has been examined by geochemical X-ray reflectance analyses. However, these analyses were not able to determine the stratigraphic origin of the skull. Carbonate nodules at the base of the Clarksburg Member and the limestone capping the Birmingham Shale were the most likely sources of the skull based on these analyses, although chemical dissimilarities with the skull matrix existed in both these strata. According to the original describers of ''Fedexia'', the carbonate nodules of the Clarksburg Member were an unlikely source because of biogenic disturbances and an abundance of siliciclastic material.〔 The holotype skull is long and is uncrushed and well preserved. Remarkably, the stapes, or middle ear bone, remains intact. Also preserved are both mandibles and the atlas-axis complex, which connects to the base of the skull.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Fedexia」の詳細全文を読む スポンサード リンク
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