Annual or perennial herb 2 - 10 cm tall Stem: delicate, growing horizontally just below the soil surface or along the surface (in very shallow water). Leaves: often buried in soil, absent or tiny, to 3 mm long, linear, with one or two roots arising from the leaf base. Flowers: borne solitary on a thin erect stem arising from the ground (scape), subtened by bracts. The violet petals are two-lipped, to 1 cm long, tipped backward and facing upward, with the three-lobed lower lip having a tiny projection. The spur (extended sac at base of petals) is nearly horizontal. Fruit: a two-valved capsule containing small seeds.
Similar species: Utricularia purpurea also has violet flowers, but the flowers are borne one to five on a stout stem. It also has whorls of apparent leaves and is free-floating.
Flowering: August to September
Habitat and ecology: Very rare in the Chicago Region, this species grows in shallow water or along pond borders. It also grows in moist, sandy ditches of recently built roads, but is choked out by other vegetation after a few years.
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. Resupinata comes from the Latin word resupinus, meaning "bent or thrown back."
Stems delicate, horizontal just below the surface of the soil or on the surface in shallow water, emitting linear lvs to 3 cm and from the base of each 1 or 2 delicate roots with or without bladders; flowering branches erect, 2-10 cm, uniflorous; bract tubular, surrounding the stem, its margin notched; fls violet, 1 cm, tipped backward on the pedicel and facing upward, the spur almost horizontal; lower lip 3-lobed, the palate scarcely developed; 2n=44. Muddy soil or very shallow water at the edge of ponds; N.S. and n. N.Y. to n. Mich., n. Minn., and sw. Ont., s. to L.I., Del. and Ind.; Ga. and Fla. July, Aug. (Lecticula r.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Reported from Lake, Marshall, Noble, and Whitley Counties. It is local and grows on wet, sandy or marl borders of lakes or in shallow water up to 10 inches deep.