Isoëtes georgiana
Amer. Fern. J. 82: 24. 1992.
Plants aquatic, emergent. Rootstock nearly globose, 2-lobed. Leaves deciduous, olive green, pale toward base, spirally arranged, to 40 cm., pliant, gradually tapering toward tip. Velum covering less that 3/4 of sporangium. Sporangium wall ± brown-streaked. Megaspores white, 450–650 μm diam., cristate to reticulate with broad, jagged ridges; girdle obscure. Microspores light brown in mass, 23–33 μm, papillose. 2n = 66.
Phenology: Spores mature late summer.
Habitat: Creeks
Discussion
Isoëtes georgiana is known only from Worth County, Georgia. An early collection from this locality was reported by B. M. Boom (1982) to be I. engelmannii x piedmontana, but the broad velum and bold texture of the megaspores suggest a possible involvement of I. flaccida.
Of conservation concern.
Selected References
None.