Flower:

Raceme of 1 to 4 bright yellow 1/3-inch snapdragon-like blooms at the top of a mostly naked reddish green stem emerging from the water. The flower has a large lower lip fanning out, an inflated pouch mid-lip, a broadly triangular upper lip half as long as the lower lip, and a stout curved spur underneath slightly shorter than the lower lip. The center pouch and upper lip typically have red venation. Each flower has a slender green stalk.

Leaves and stem:

Leaves are integrated within the surface of the boggy soil. Finely branching stems to 6 inches long with 6 to 14 nodes from which extend spidery filamentous but flattened foliage, up to ¾ inch long, and fine fibrous roots. Small bladders for capturing micro-organisms are present on specialized stems, but nearly impossible to observe without careful extraction from the boggy mud in which they are emersed. The flowering stem has a few minute scale-like leaves alternately attached.

Notes:

Flat-leaved Bladderwort is another one of Minnesota's carnivorous plant species. While it is not as widespread as the common bladderwort (Utricularia macrorhiza), it can be frequently happened upon searching shallow marshy areas of many lakes and open wetlands. There are 7 bladderwort species in Minnesota, most with yellow flowers and similar leaves. Distinguishing features are the size and shape of the spur, the general shape of the flowers, including relative sizes of the upper and lower lips, the bladder size and location. Flat-leaved Bladderwort bladders are mostly unseen, the lower lip on the flower is twice as large as the upper lip, and flowers up to about 1/3 inch long.