Viola x brauniae

Perennial herb 5 - 30 cm tall Stem: erect to spreading, robust, mostly hairless, producing both leaves and flowers. Leaves: both basal and alternate, stalked, irregularly round-toothed, 2 - 5 cm long, broadly egg-shaped to heart-shaped with indented base and tapered to a pointed tip. The stipules are green, 1 - 2 cm long, lance-shaped to egg-shaped, and obviously fringed along the edges. Flowers: in upper leaf axils, long-stalked, pale lavender with dark purple center, about 1.5 - 2.5 cm long, bilaterally symmetric with two upper petals, two lateral petals, and lower petal with base modified into a thick, rounded, obvious nectar spur. In the summer, producing very fertile flowers that do not open (cleistogamous). Sepals: five, green, sparsely fringed with slender bristles, lance-shaped with obvious ear-like appendages (auricles) at base, and long-pointed tips. Petals: five, separate, all differently shaped, pale light purple with darker area near base. The two lateral petals have a beard of many threadlike hairs, and the lowest petal is prolonged at its base into a thick, 2 - 5 mm long, rounded spur. Stamens: five, separate, but very tightly arranged so anthers touch as they surround ovary. The filaments are very short, and the lower two stamens have spur-like nectaries on their backs that extend into the spur of the lower petal. Pistil: with a single-chambered, superior ovary; and a single slender style that curves slightly upwards below the stigma.

Similar species: Viola x brauniae is intermediate between its parents. The presence of flowers with a dark purple eyespot is shared with V. rostrata, but that parent has sharp short-toothed leaves with slightly more narrow stipules, no bristles on the sepals, and the flower has a very long (7 - 15 mm), slender spur and no beard of hairs on the lateral petals. The other parent of the hybrid, V. striata, is most easily recognized by its cream-white to ivory flowers.

Flowering: April to June

Habitat and ecology: Not common (probably often overlooked), in areas bordering swamps and floodplains where the two parent species also occur.

Occurence in the Chicago region: native

Notes: This hybrid of V. rostrata and V. striata was first documented in 1917 near Cincinnati, OH by the astute observance and collections by Dr. E. Lucy Braun. The hybrid is sterile and fails to produce viable seed. While it has only been confirmed to occur in Berrien Co., MI at present, it is likely to exist elsewhere in the Chicago Region where the two parent species co-occur. Old collections and current observances may be erroneously attributed to one of the parent species.

Etymology: Viola is the classical name for the genus. Brauniae is named after Dr. E. Lucy Braun, discoverer of the hybrid, and a diligent botanist of the Ohio flora in the early 1900's.

Author: The Field Museum