| Author | B.D. Greene ex Bigelow | |
| Distribution | Known only from the shores of two very large natural lakes -- Phelps in Washington County and Waccamaw in Columbus County. The collection records were made after RAB (1968) was published.
This bladderwort has a highly fragmented and bimodal range, indicating its overall rarity or highly selective habitat requirements. It occurs over southeastern Canada, south to New England and the Great Lakes region. South of this region it is mainly found in scattered sites from NJ south to southern FL and southern AL. The BONAP map and NatureServe show no records yet for OH, VA, WV, and KY, showing how scarce it is across the central part of its range. | |
| Abundance | Very rare, and found only at two known sites in NC. This is, not surprisingly, a State Endangered species. The fact that lakes (as do ponds) can greatly fluctuate in water levels owing to drought and flooding events, plus the concern about pollution, algal blooms, and other negative factors in natural lakes makes it clear that this species and others (including rare fishes and mussels) restricted to these habitats are always at peril. | |
| Habitat | As mentioned above, in NC the species is found only along small sections of the shorelines of large natural lakes. It grows rooted in mud or wet sand along the shores, and it is not a floating species of deep water. In other parts of its range, it can grow in pond margins and wet flatwoods. | |
| Phenology | Blooms from June to September, and fruits shortly after flowering. | |
| Identification | This is the second of only two pink-flowered species of bladderworts in the state, being the "rare one". It has its leaves rooted in mud, and it grows normally in only 1-inch of water or less, along the shorelines of natural lakes. It is a tiny plant, with a very slender and erect scape reaching upward only to about 2-4 inches high. The tiny flower, normally just a single one per stalk, is about 1/3-inch wide or less. As the scientific name implies, it is "resupinated", tilted back as to face upward, with the very short spur being horizontal. Unlike with U. purpurea, the lip is rather flat and is not inflated into a sac or pouch (like a tiny lady's-slipper flower); that species also grows in deeper water, with floating leaves. Though U. resupinata does grow in colonies, the sites in NC are typically just 20-50 individuals, often growing near other species, and thus an observer does not normally obtain a "pink spectacle" as with a stand of U. purpurea. In fact, you likely will need binoculars or a hand lens, get down on your knees (keeping them or your pants as dry as possible), and then can appreciate the flowers of this species! However, as water levels of these two lakes can vary considerably owing to weather events, your visit may coincide with a "bad water level", and the water is too high or too low for the plants to thrive and even be seen at all. | |
| Taxonomic Comments | None
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| Other Common Name(s) | Northeastern Bladderwort, Resupinate Bladderwort | |
| State Rank | S1 | |
| Global Rank | G4 | |
| State Status | E | |
| US Status | | |
| USACE-agcp | OBL link |
| USACE-emp | OBL link |
