Global Range: (5000-200,000 square km (about 2000-80,000 square miles)) The orginal range was much larger and more discontinuous than the current range which is a small narrow area of shale ridges from south-central Pennsylvania into Virginia and isolated occurrences in Ohio.The maps in popular guides tend to overstate the original range which actually was in several disjunct parts. The core of the range was the shale region from about Huntington County, Pennsylvania southwest though northeastern West Virginia and adjacent Virginia including a bit of far western Maryland. These populations reached east, not exclusively on shale, to Lancaster and Dauphin Counties, Pennsylvania in the 1950s and Washington, D.C. in the 1880s (specimen from Rock Creek Park in Academy of Natural Sciences). There are no gaps more than two counties wide from Dauphin County and D.C. to extreme southwest Virginia and (LeGran and howard, 2008) adjacent North Carolina. There were also a few seemingly isolated records in the early 1970s for central New York which could have been an extension of the main range. There were disjunct well known populations in the trap rock glades region and surrounding areas in northern New Jersey (specimens from seven counties, Iftner and Wright, 1996) and immediately adjacent New York into the late 1950s. There are or were several apparently disjunct populations in southern Ohio. Consult Shapiro (1974) for New York, Iftner et al. (1993) for Ohio, and Allen (1997) for West Virginia. A separate and distinctive group of populations in northern Michigan has traditionally also been included with this taxon but see taxonomy field. Minnesota populations should be referred to the taxon freija. The pre-1863 Long Island record was probably in error for a nearby part of New Jersey or New York since no likely edaphic formations occur on Long Island. The Cook Co., Illinois dot shown by Parshall (2002) is very dubious and has generally been ignored. This also seems to date from around 1900 or earlier and collectors were often sloppy with data in those days. Information on the three reports along Lake Erie in New York and Ohio (Parshall, 2002, Shapiro, 1974) is unavailable. Aside from omitting the seven New Jersey counties, the map in Parshall (2002) seems to be the most complete compilation. The Kentucky record was probably false.
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