Shinners, as noted in the above synonymy, recognized plants from the Edwards Plateau regions of central Texas as a distinct species, but Cantino (1982) thought otherwise.
Named for its narrow leaves.
As noted by Cantino (1980), this is an uncommon species, known by relatively few extant populations.
Named for the late Donovan S. Correll, prolific worker on many plant groups and co-author of the Manual of the Flora of Texas (1970).
As noted by Cantino (1980), one of the most distinctive species of the genus and "easily recognized by its overall robustness, its large, broadly obovate to elliptic, entire to bluntly toothed leaves ..." Nevertheless it does appear close to the equally robust P. correllii, from which it is largely distinguished by its mostly epunctate leaves and calyces.
Named for its resemblance to the genus Digitalis (Scrophulariaceae).
Among Texas species this taxon is readily recognized by its small flowers.
Named for its intermediate appearance to yet two other species, these not named by its author.
Among Texas species this taxon is most closely related to P. angustifolia and P. pulchella. Cantino in his original description makes a strong case for its recognition, but this needs to be confirmed by field studies in the area concerned.
Closely related to P. angustifolia and perhaps not specifically distinct. The two taxa are in need of additional field study.
Named for its beautiful flowers.
A widespread highly variable species, this compounded by garden cultivars from Europe which escaped here and there making identification difficult. Cantino recognized two morphogeographical infraspecific taxa, a more northeastern var. virginiana and a more southwestern var. ARENARIA Shimek (although he treated these as subspecies; cf Cantino: Rhodora 85: 263. 1983). The P. virginiana complex is in need of additional field study.
Named for the state of Virginia, from which first described.