Perennial herb 4 - 15 cm tall Stem: creeping along soil, forming mats in shallow water. Leaves: submersed, numerous, 3 - 10 mm long, often three-parted at base and forking one to three times into flattened and slender segments. Terminal segments are pointed at the tip, non-toothed and as wide as the lower segments. Bladders formed along leaf segments. Flowers: borne two to nine (rarely to fifteen) on an emersed stalk (scape), yellow petals are two-lipped with upper lip less than half as long as the 4 - 8 mm lower lip, lower lip having an inconspicuous projection. The spur (extended sac at base of petals) is less than half as long as the lower lip. Fruit: a two-valved capsule containing small seeds.
Similar species: Utricularia radiata, Utricularia intermedia, Utricularia macrorhiza, Utricularia geminiscapa, and Utricularia gibba are other aquatic or amphibious Utricularia species with dissected leaves. The flower stalk of Utricularia radiata has a whorl of leaves with inflated petioles. Utricularia macrorhiza, U. geminiscapa, and U. gibba have leaf divisions that are circular in cross-section. Utricularia intermedia differs by its terminal leaf divisions that are toothed (10x magnification required) and traps that are usually borne on separate branches.
Flowering: mid June to early August
Habitat and ecology: Rare in shallow water, ponds, large swales, and bogs.
Occurence in the Chicago region: native
Etymology: Utricularia comes from the Latin word utriculus, meaning "a small bottle."This refers to the insect-trapping bladders on the leaves and runners of the bladderworts. Minor means small.
Stems mostly creeping on the soil and forming mats under shallow water; lvs numerous, mostly 0.3-1 cm, commonly 3-parted at base and then dichotomous or irregularly 1-3 times divided, the segment slender, flat, the ultimate ones strongly acuminate; fls mostly 2-9(-15) in a lax raceme on an emergent peduncle 4-15 cm; pedicels soon arcuate-recurved; cor yellow, the lower lip 4-8 mm, twice as long as the upper, the palate scarcely developed; the spur small, to half as long as the lower lip; 2n=44. Shallow water; circumboreal, s. to N.J., Ind., and Calif.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.