Isoëtes virginica

N. E. Pfeiffer

Claytonia 3: 29. 1937.

Common names: Virginia quillwort
Synonyms: Isoëtes virginica var. piedmontana N. E. Pfeiffer Isoëtes piedmontana
Treatment appears in FNA Volume 2.

Plants becoming terrestrial. Rootstock nearly globose, 2-lobed. Leaves deciduous, dull green, pale to dark-brown toward base, spirally arranged, less than 30 cm, pliant, gradually tapering to tip. Velum covering less than 1/3 of sporangium. Sporangium wall brown-streaked to completely brown. Megaspores white, 400–480 μm diam., boldly tuberculate to rugulate with cristate, occasionally branched to anastomosing ridges; girdle obscure. Microspores light-brown in mass, 27–33 μm, spinulose. 2n = 22, 44.


Phenology: Spores mature late in spring–early summer.
Habitat: Mud flats and depressions on and around granite outcrops

Discussion

Short plants with 15 to 50 leaves and a tendency toward lower and more open megaspore ornamentation have been called Isoëtes virginica var. piedmontana Pfeiffer.

Selected References

None.

Lower Taxa

None.
... more about "Isoëtes virginica"
several +  and 1 +
W. Carl Taylor +, Neil T. Luebke +, Donald M. Britton +, R. James Hickey +  and Daniel F. Brunton +
N. E. Pfeiffer +
Virginia quillwort +
alternating +
Ala. +, Ga. +, S.C. +  and Va. +
Mud flats and depressions on and around granite outcrops +
pale +  and dark-brown +
straight +
deciduous +
recurved;erect;spreading +
tapering +
0 cm0 mm <br />0 m <br /> (30 cm300 mm <br />0.3 m <br />) +
deltate;cordiform +
0.1 cm1 mm <br />0.001 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
membranous +
occasionally branched +  and anastomosing +
boldly tuberculate +  and rugulate +
Spores mature late in spring–early summer. +
branched +  and simple +
2-lobed +  and globose +
0.3 cm3 mm <br />0.003 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
brown-streaked +  and completely brown +
Isoëtes virginica var. piedmontana +  and Isoëtes piedmontana +
Isoëtes virginica +
Isoëtes +
species +
brown-streaked;completely brown +
ephemeral +, evergreen +  and perennial +