Comments: Subspecies allapaticola and anastasae were synonymized with other subspecies by Boone (1995) and Boone et al. (1993), who found that patterns of allozyme variation in P. gossypinus are not concordant with the ranges of the nominal subspecies.
Boone et al. (1999) examined range-wide allozyme variation in P. gossypinus and found that genetic similarity generally reflected geographic proximity; the most divergent populations were from Georgia and Florida sea islands; each population was more or less distinct.
Has hybridized with P. leucopus under laboratory conditions, but the distinctiveness of this species in the field is well documented (see Musser and Carleton, in Wilson and Reeder 1993, 2005).