The identity of Viola conspersa Reichen. (Violaceae)
Viola conspersa Reichen. has been unanimously recognized by past violet researchers and regional floristicians (e.g., Brainerd, Cronquist, Fernald, Russell). This taxon belongs to a group of caulescent plants with cyanic flowers and slender styles that includes V. adunca J.E. Smith and V. labradorica Schrank. It was recognized apart from those species primarily by leaf blade and stipule morphology. Important to this discussion is that the United States distribution of V. labradorica has been debated. Brainerd (1921) considered V. labradorica to be a northern plant that reached its southern limit in the higher mountains of New England and New York. Russell (1965), however, felt it was extremely limited in the United States and reported it from only three locations, one of which was Mt. Washington, NH.
The status of Viola labradorica has also been debated. Fernald (1950) considered this plant closely allied to V. adunca, as both taxa had +/- truncate leaf blades, and referred to it as V. adunca var. minor (Hook.) Fern. Russell (1965) disagreed with this stance and considered V. labradorica a separate species that was more similar to and replaced V. conspersa to the north. Russell's interpretation was closer to the mark.
Ballard (1992) studied this group of species (Viola section Viola) throughout North America. He found that leaf blade shape and prominence of teeth on stipules were, in part, modified by environment. Plants referable to V. conspersa showed cordate leaf blades and prominently toothed stipules in the south and at low elevations, whereas plants collected northern and/or high elevation sites had more truncate blades and smaller teeth on the stipules. In fact, when specimens were examined from throughout the range of the species, there were no distinctions between V. conspersa and V. labradorica (i.e., V. labradorica represented an environmental form of V. conspersa with truncate blades and nearly entire stipules, these features controlled largely by latitude and altitude). Given that they both represent the same plant (i.e., they are taxonomic synonyms), only one name can be used. Viola conspersa was described in 1823, whereas V. labradorica was described in 1818. The name V. labradorica, therefore, has priority and should replace the use of the name V. conspersa.
Literature Cited
Ballard, H.A. 1992. Systematics of Viola section Viola, in North America north of Mexico. M.S. Thesis, Central Michigan University, Mount Pleasant, MI.
Brainerd, E. 1921. Violets of North America. Vermont Agricultural Experiment Station 224: 1–172.
Fernald, M.L. 1950. Gray's Manual of Botany, 8th edition. Van Nostrand Reinhold Company, New York, NY.
Russell, N.H. 1965. Violets (Viola) of central and eastern United States: an introductory survey. Sida 2: 1–113.