Isoëtes tuckermanii

A. Braun ex Engelmann in A. Gray

in A. Gray,Manual ed. 5 676. 1867.

Common names: Tuckerman's quillwort isoète de Tuckerman
Treatment appears in FNA Volume 2.

Plants aquatic, occasionally emergent. Rootstock nearly globose 2 (–3) -lobed. Leaves evergreen, olive green to reddish-brown, pale toward base, spirally arranged, to 20 cm, pliant to rigid, gradually tapering to tip. Velum covering less than 1/2 of sporangium. Sporangium wall brown-streaked. Megaspores white, 450–650 μm diam., reticulate with ridges having irregular and roughened crests; girdle densely papillate. Microspores gray in mass, 25–35 μm, spinulose. 2n = 44.


Phenology: Spores mature in late summer.
Habitat: Slightly acid lakes, ponds, and streams

Distribution

V2 671-distribution-map.gif

N.B., Nfld. and Labr. (Nfld.), N.S., Ont., Que., Conn., Maine, Mass., N.H., N.J., N.Y., R.I., Vt.

Discussion

Isoëtes tuckermanii may be an allotetraploid like I. riparia, but it appears to have had different parental species. Variation may also have resulted from multiple allotetraploid origins. Typical plants of I. tuckermanii have thin, soft leaves. More northern plants, referred to as I. tuckermanii var. borealis A. A. Eaton, have thick, stiff leaves.

Isoëtes tuckermanii hybridizes with I. echinospora; I. engelmannii [ = I. x foveolata A. A. Eaton ex Dodge]; and I. lacustris [ = I. x harveyi A. A. Eaton].

Selected References

None.

Lower Taxa

None.
... more about "Isoëtes tuckermanii"
several +  and 1 +
W. Carl Taylor +, Neil T. Luebke +, Donald M. Britton +, R. James Hickey +  and Daniel F. Brunton +
A. Braun ex Engelmann in A. Gray +
Tuckerman's quillwort +  and isoète de Tuckerman +
alternating +
N.B. +, Nfld. and Labr. (Nfld.) +, N.S. +, Ont. +, Que. +, Conn. +, Maine +, Mass. +, N.H. +, N.J. +, N.Y. +, R.I. +  and Vt. +
papillate +
Slightly acid lakes, ponds, and streams +
pale +, olive green +  and reddish-brown +
straight +
evergreen +
recurved;erect;spreading +
tapering +
0 cm0 mm <br />0 m <br /> (20 cm200 mm <br />0.2 m <br />) +
pliant +  and rigid +
deltate;cordiform +
0.1 cm1 mm <br />0.001 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
membranous +
Spores mature in late summer. +
in A. Gray,Manual ed. 5 +
branched +  and simple +
2(-3)-lobed +  and globose +
0.3 cm3 mm <br />0.003 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Isoëtes tuckermanii +
Isoëtes +
species +
brown-streaked;completely brown +
ephemeral +, evergreen +  and perennial +