VERTEBRATE FOOTPRINTS FROM THE U. S. NATIONAL MUSEUM'S "LACOE COLLECTION" FROM THE MIDDLE PENNSYLVANIAN LLEWELLYN FORMATION, EASTERN PENNSYLVANIA USA

Currently, only a single set of vertebrate footprints has been published from the Pennsylvanian Llewellyn Formation in eastern Pennsylvanian (type specimen of Anthracopus ellangowensis, Leidy, 1879). Additional tracks and trackways have been discovered in the “Lacoe Collection” housed at the United States National Museum of Natural History (USNM), Washington, DC.

Ralph Dupuy Lacoe (1824-1901) was a self-taught paleontologist who lived in the small coal town of Pittston, Pennsylvania, whose significant contributions to paleontology were widely acknowledged at the time but now are largely unrecognized. Lacoe retired early from his business endeavors and worked full time collecting more than 100,000 fossil specimens, primarily from eastern North America. He donated most of his collection to the USNM in 1898, to be studied further by leading scientists of the time, including Charles A. Ashburner (invertebrate fossils from Carboniferous limestone beds); Edward D. Cope, Roy L. Moodie (tetrapod vertebrate remains); Frank H. Knowlton, Leo Lesquereux (Coal Flora paleobotany); and Anton Handlirsch, Samuel H. Scudder (Carboniferous fossil insects).

Almost unnoticed in the USNM “Lacoe Collection” are several sandstone specimens bearing vertebrate footprints discovered in the mining spoils from the Butler Coal Mine, Northern Anthracite Coal Field, Pittston, PA. The specimens originated from the sandstone strata immediately above the “Pittston” coal seam of the Llewellyn Formation, indicating a Middle Pennsylvanian (Westphalian D) age.

The “Lacoe” set of footprint specimens display tetradactyl manus and tridactyl pes underprints and imprints. Manus digits are normally short, pes digits relatively long, all digits typically straight and blunt tipped, but slightly curved digits and pointed tips are also present. Body/tail drags are not evident. The footprints demonstrate associated manus/pes pairs with pes much larger than manus, and approximate pes widths and lengths that range from 40 to 50 mm, allowing the interpretation of the footprints as Mathewichnus isp., produced by a temnospondyl trackmaker.