Hottonia inflata Ell.
Habitat: Pools and ditches. [Open water (non-forested, wetland); Forested wetland].
Range: Florida to Texas, north to New England and west to Missouri. Rare in New York, Rhode Island, Pennsylvania, Maryland, and Delaware.
Aids to Identification: Featherfoil is a short-lived aquatic herb with an entirely submerged, spongy, densely leafy, hollow stem. The successive segments of the stem become progressively shorter bearing a terminal umbel of racemes. The white flowers are small (5-8 cm) in whorled verticils of 2-10 at the joints. The leaves are sessile, or nearly so, oblong (2-6 cm) and divided into narrowly, linear entire segments.
Ecological characteristics: Known populations occur in vernal pools in southern Maine. The species is believed to be a winter annual, with seeds germinating in the fall and resuming growth in the spring.
Phenology: Flowers in June.
Synonyms: None noted.
Known Distribution in Maine: This rare plant has been documented from a total of 4 town(s) in the following county(ies): Washington, York.
Reason(s) for rarity: Local throughout much of its range and here at its northern limit.
Conservation considerations: This plant is restricted statewide to southern Maine, and populations are vulnerable to conversion of their habitat to residential or commercial use.