DACF Home → Bureaus & Programs → Maine Natural Areas Program → Communities, Plants, and Animals → Rare Plants → Zosterella dubia
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Zosterella dubia (Jacq.) Small
Water Stargrass
- State Rank: S3
- Global Rank: G5
- State Status: Special Concern
Habitat: Damp sands, often submerged in quiet waters. [Open water (non-forested, wetland)]
Range: Southern Quebec to North Dakota and Washington, south to Cuba and South America.
Aids to Identification: This perennial aquatic plant usually grows in shallow water with its stem submersed. The leaves are grass-like and up to 15 cm long. The flowers are pale yellow, and the fruits are black. It can be recognized vegetatively by its alternate, narrow, parallel-sided leaves with many fine veins. The leaves lack a more prominent central vein.
Ecological characteristics: In Maine, this species may occur along shallow shorelines or in open water.
Phenology: Flowers June - September.
Family: Pontederiaceae
Synonyms: Formerly known as Heteranthera dubia (Jacq.) MacM.
Known Distribution in Maine: This rare plant has been documented from a total of 10 town(s) in the following county(ies): Aroostook, Hancock, Kennebec, Penobscot, Somerset, Waldo.
Dates of documented observations are: 1940, 1960, 1981, 1990 (3), 1999 (3), 2000, 2002 (2)
Reason(s) for rarity: At northern limit of range.
Conservation considerations: Maintain water quality in the lakes and ponds in which it occurs.