| Author | S. Ware | |
| Distribution | Known only from Granville County, in the northeastern Piedmont, as well as in Franklin County, VA -- the entire range of the species. The species was described in 2011. | |
| Abundance | Extremely rare in NC, perhaps gone from one site, but still present in small to moderate numbers at another, in the Butner area in Granville County. Note that the very similar P. teretifolius is not known from these NC sites. This is a State Endangered species. It is rare enough globally to be Federally listed. | |
| Habitat | The species is known to occur only on mafic rocks -- on diabase flatrocks in Granville County, and on ultramafic barrens in VA. It occurs in places where there is some seepage on the rocks. |
| Phenology | Blooms from July to September, perhaps in late June; it fruits soon after flowering. This species flowers only in the afternoon; according to Weakley (2018) from about 1-7 pm (EDT), as opposed to about 3-7 pm (EDT) in the much more widespread P. teretifolius. | |
| Identification | The species is extremely similar to P. teretifolius, with the cluster of ascending, short, linear, and terete (round in cross-section) basal leaves, all of which are succulent and pale green. The flowering stem is 4-6 inches tall, with a handful of rich rose-colored flowers, with 5 rounded petals, at the top, each about 2/3-inch across. In this species, there are 25-80 stamens, usually quite a bit more than in the widespread species, which has 12-30 stamens. Also, the styles in this species are 3.8-7 mm long; those of the other species are only 2-3.5 mm long, and thus "shorter than or about the same length as the stamens" (Weakley 2018). | |
| Taxonomic Comments | When this taxon was first discovered in the 1980's, it was considered different owing to the high stamen number, as perhaps an undescribed species. It had been put into one or two other species briefly, but uncomfortably, though it was clear to experts it was not simply a variety of P. teretifolius. Finally, in 2011, it was described as new to science.
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| Other Common Name(s) | Piedmont Rock-pink | |
| State Rank | S1 | |
| Global Rank | G1 | |
| State Status | E | |
| US Status | | |
| USACE-agcp | | |
| USACE-emp | | |
