A family of a single genus and about 250 species.
Isoetes Linnaeus (Quillwort, Merlin's-grass)
References: Taylor et al. in FNA (1993b); Boom (1982); Kott & Britton (1983).
A genus of about 250 species, cosmopolitan in distribution.
Isoetes engelmannii A. Braun. [= FNA; I. engelmannii -- RAB, C, in part only (also see I. caroliniana and I. hyemalis); I. engelmannii var. engelmannii -- K]
Isoetes hyemalis Brunton, Winter Quillwort. Cp (NC, SC, VA), Pd (NC, VA): (VA Rare List). Endemic to an area from sc. VA south through e. and c. NC to GA and AL, in the Coastal Plain and lower Piedmont. See Brunton, Britton, & Taylor (1994) and Brunton & Britton (1996a) for additional information on this species. [I. engelmannii -- RAB, in part] Isoetes lacustris Linnaeus, Lake Quillwort. Mt (VA): (VA Rare List). [= FNA, C; I. macrospora Durieu -- K]
Isoetes melanopoda Gay & Durieu ex Durieu. Pd (NC, SC, VA): (VA Rare List). [= FNA, K, C; I. melanopoda -- RAB, in part only (also see I. melanospora, I. virginica, I. piedmontana)]
Isoetes melanospora Engelmann, Black-spored Quillwort. [= FNA, K; I. melanopoda -- RAB, in part]
Isoetes piedmontana (N.E. Pfeiffer) C.F. Reed. (VA Rare List). [= K; I. melanopoda -- RAB, in part; I. virginica -- FNA, in part]
Isoetes riparia Engelmann ex A. Braun. Shore Quillwort. (VA Watch List). [= RAB, FNA, C; I. riparia var. riparia -- K]
Isoetes valida (Engelmann) Clute, Carolina Quillwort. Mt (NC, SC, VA): bogs (growing in Sphagnum), pools, ponds; common. [I. caroliniana (A.A. Eaton) N. Luebke -- FNA; I. engelmannii -- RAB, C, in part; I. engelmannii A. Braun var. caroliniana A.A. Eaton -- K]
Isoetes virginica N.E. Pfeiffer, Virginia Quillwort. Mt (VA), Pd (NC?, SC?, VA): (US Species of Concern, VA Rare List). See Brunton, Britton, & Wieboldt (1996). [= C; I. melanopoda -- RAB, in part; I. virginica -- FNA, in part (also see I. piedmontana); I. melanopoda Gay & Durieu ex Durieu -- K, in part]
I. boomii N. Luebke is known only from Laurens County, GA.
I. butleri Engelmann occurs in calcareous areas of the midwest, extending east to c. TN and n. AL.
I. flaccida A. Braun occurs in the Coastal Plain of GA and FL.
I. georgiana N. Luebke is known only from GA (Colquitt, Dodge, Irwin, Tift, Tucker, Turner, and Worth counties). See Brunton & Britton (1996b) for additional information.
I. tegetiformans Rury occurs in shallow pools on granite flatrocks in ne. GA, near the SC line.
Flora of the Carolinas and Virginia, Working Draft of 27 October 1997 -- KEY TO PTERIDOPHYTE GENERA. Alan S. Weakley. The Nature Conservancy, Southeast Regional Office, Southern Conservation Science Department.