Asplenium platyneuron plant. Similar buds have also been reported from the single-sorus spleenwort, "Asplenium monanthes". The species most similar to "Asplenium platyneuron" is the black-stemmed spleenwort, "A. resiliens". However, this stipe of this species is darker, and the pinnae are opposite, rather than alternate, along the rachis. Neither black-stemmed spleenwort nor the other pinnate American spleenworts have dimorphic fertile and sterile fronds. It might be confused with a young Christmas fern, "Polystichum acrostichoides", but that species is generally much larger and has a green, scaly stipe and rachis. It is very similar to Boydston's spleenwort, "Asplenium × boydstoniae", a backcross with Tutwiler's
Asplenium × wherryi ("A. platyneuron") and mountain spleenwort. In theory, "A. × wherryi" might be found anywhere the ranges of its parental species overlap, stretching down the Appalachian Mountains from New York to Georgia and in the Shawnee Hills of Indiana and Kentucky. In practice, it is quite uncommon and scattered. It has been reported from New Jersey, Lancaster County, Pennsylvania, Virginia, Kentucky, and Whitfield County, Georgia. The Pennsylvania report consisted of a single plant which grew for a few years at Tucquan Glen. The type locality in New Jersey was reported destroyed in 1956, although "A. bradleyi" was rediscovered there in 1960.