Viola brittoniana Pollard. Section: Nosphinium. Subsection: Borealiamericanae. Phen: Chasmogamous flower Apr–Jun; chasmogamous fruit May-Jul; cleistogamous fruit Jul-Aug. Hab: Moist to seasonally inundated sandy soils of fields, meadows, trail edges, and forest clearings adjacent to rivers and coastal marshes, also peaty river shores. Dist: MA to SC, along the coast.
ID notes:This homophyllous cut-leaved species has been most frequently confused with other members of the Pedatifida and Subsinuata species groups. It differs from V. pedatifida in its ovate cordate biternately divided leaf blades and with other features noted in the key, sepals eciliate (but auricles occasionally ciliolate), and slightly smaller seeds. It is easily separated from V. baxteri and V. subsinuata by its glabrous petioles and peduncle, leaf blades appressed-hirtellous along veins and ciliolate along margins, lanceolate to linear-lanceolate acuminate sepals and prominent auricles, densely bearded spurred petal, unspotted cleistogamous capsule on tall erect peduncle, and unspotted brown to orange-brown seeds. Both this and V. septemloba grow along the Atlantic Coastal Plain, with almost non-overlapping local ranges, but the two have been misidentified for each other. This species differs from the heterophyllous V. septemloba in all leaf blades being divided, the largest thinner and biternately divided with the terminal lobe of the terminal primary division usually narrow, blade surfaces appressed-pubescent along veins, and ciliolate margins, the chasmogamous peduncle often held among the leaves, often smaller flower, and smaller medium brown seeds.
Origin/Endemic status: Native
Synonymy: = F, FNA6, K4, NE, Pa, Va, Ballard () (in prep), Ballard, Kartesz, & Nishino (2023), Gil-ad (1998), Gil-ad (1998), Haines (2001); = Viola brittoniana Pollard var. brittoniana – G, K1, K2, RAB; = Viola pedatifida G.Don ssp. brittoniana (Pollard) L.E.McKinney – McKinney & Russell (2002); < Viola palmata L. var. palmata – C