This widespread eastern species appears to intergrade with several other stemless blue violets; 2n = 54 in all species of this section. V. affinis has sometimes been confused or combined with the following: (1) the glabrous missouriensis, with deltoid-ovate leaves; (2) the largely glabrous communis (to which V. latiuscula Greene may appear transitional); and (3) the more uniformly pubescent sororia. McKinney & Russell (2002; J) have included affinis completely within missouriensis, as a variety of sororia, but other authors have continued to recognize it as a species (Gil-ad 1997, 1996; W; H. Ballard, in prep.). Identification is often difficult and some records mapped here are tentative. V. affinis differs from communis and sororia as follows (based partly on H. Ballard, in prep.): spurred petals are densely bearded as well as the laterals (like cucullata); auricles are short and rounded (versus prominent, up to 4 mm); cleistogenes are on ascending to erect peduncles (approaching cucullata but not erect-sinuous as in communis or short as in sororia); and capsules are often hirtellous, unlike other species of Boreali-Americanae (Gil-ad 1997, 1998); seeds are yellow- to orange-brown or purple-black (versus dark brown to black). Leaves of affinis tend to be relatively small, narrow and somewhat deltoid-triangular, gradually tapering to acutish tips (approaching missouriensis); they are more densely reddish-punctate, and generally glabrate except for small thinly scattered hairs confined to the upper surface, especially on the basal lobes. V. affinis can also intergrade with hirsutula (typically on drier sites), which has hairs scattered more widely over upper leaf surfaces. Based on Sm, D, B, F and personal experience, typical habitat for affinis is moist or damp woodlands and edges, especially in gullies or near streams on relatively acid, sandy soils (in contrast to communis and missouriensis on more base-rich or clayey soils).