Isoëtes lithophila

N. Pfeiffer

Ann. Missouri Bot. Gard. 9: 135. 1922.

Common names: Rock quillwort
Treatment appears in FNA Volume 2.

Plants becoming terrestrial. Rootstock nearly globose, 2-lobed. Leaves deciduous, bright green, pale toward base, spirally arranged, to 12 (–20) cm, pliant, gradually tapering to tip. Velum covering entire sporangium. Sporangium wall unpigmented. Megaspores light gray to gray-brown, 290–360 μm diam., obscurely rugulate with low ridges; girdle obscure. Microspores brown in mass, 30–33 μm, tuberculate to spinulose. 2n = 22.


Phenology: Spores mature in winter or spring.
Habitat: Shallow depressions on granite outcrops

Discussion

Isoëtes lithophila is known from granite outcrops in Burnett, Mason, and Llano counties in south central Texas.

Of conservation concern.

Selected References

None.

Lower Taxa

None.
... more about "Isoëtes lithophila"
several +  and 1 +
W. Carl Taylor +, Neil T. Luebke +, Donald M. Britton +, R. James Hickey +  and Daniel F. Brunton +
N. Pfeiffer +
Rock quillwort +
alternating +
Shallow depressions on granite outcrops +
12 cm120 mm <br />0.12 m <br /> (20 cm200 mm <br />0.2 m <br />) +
pale +  and bright green +
straight +
deciduous +
recurved;erect;spreading +
tapering +
0 cm0 mm <br />0 m <br /> (12 cm120 mm <br />0.12 m <br />) +
deltate;cordiform +
0.1 cm1 mm <br />0.001 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
membranous +
light gray +  and gray-brown +
tuberculate +
Spores mature in winter or spring. +
Ann. Missouri Bot. Gard. +
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 />) +
Isoëtes lithophila +
Isoëtes +
species +
brown-streaked;completely brown +
ephemeral +, evergreen +  and perennial +