Isoëtes tegetiformans
Ann. Missouri Bot. Gard. 68: 100. 1978.
Common names: Mat-forming Melin's grass
Treatment appears in FNA Volume 2.
Revision as of 23:22, 29 July 2020 by imported>Volume Importer
Plants becoming terrestrial. Rootstock horizontally elongate, mat-forming, often proliferous. Leaves deciduous to nearly evergreen, bright green, pale toward base, distichously arranged, to 4 cm, pliant, gradually tapering to tip. Velum covering entire sporangium. Sporangium wall unpigmented. Megaspores dark gray, 275–370 μm diam., tuberculate with low and distinct tubercules; girdle obscure. Microspores brown in mass, 26–33 μm, spinulose. 2n = 22.
Phenology: Spores mature late winter and spring.
Habitat: Shallow pools on granite outcrops
Discussion
Isoëtes tegetiformans is a unique mat-forming quillwort distinguished by its distichous leaf arrangement, horizontally elongate rootstock, and nondichotomous roots. (See discussion under I. melanospora.)
Of conservation concern.
Selected References
None.
Lower Taxa
None.
... more about "Isoëtes tegetiformans"
separating +
Mat-forming Melin's grass +
alternating +
Ga. +
vascular +
surrounding +
vascular +
obscure +
several +
Present +
septate +
longitudinal +
simple +
arranged +
straight +
deciduous;nearly evergreen +
pliant +
recurved;erect;spreading +
surrounding +
tapering +
deltate;cordiform +
membranous +
exposed +
endosporic +
trilete +
dark gray +
tuberculate +
globose +
9-celled +
monolete +
spinulose +
brown +
reniform +
textured +
brownish +
several +
fibrous +
hardened +
converging +
Ann. Missouri Bot. Gard. +
1978 +
arising +
cormlike +
brown +
mat-forming +
proliferous +
elongate +
hardened +
multitailed +
unpigmented +
Isoëtes tegetiformans +
Isoëtes +
species +
distinct +
brown-streaked;completely brown +
terrestrial +
heterosporous +