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western moonwort

Paradox moonwort, peculiar moonwort, two-spike moonwort

Pinnae

to 6 pairs, ascending, usually approximate or overlapping except in shade forms, distance between 1st and 2d pinnae not or slightly more than between 2d and 3d pairs, basal pinna pair commonly much larger and more divided than adjacent pair, lobed to tip, basal pair oblong to oblong-lanceolate with lobed margins, remainder broadly spatulate with entire margins or 1 or more shallow lobes, apex rounded, venation pinnate.

Trophophore(s)

stalk 0–3(–10) mm, to 1/4 length of trophophore rachis;

blade ± gray-green, dull, oblong-linear to deltate, 1–2-pinnate, to 6 × 5 cm, firm.

converted entirely to second fertile segment, stalk 1/2 length of fertile segment.

Sporophores

1–3 pinnate, 2–3 times length of trophophore.

double, 2 per leaf, 1-pinnate, 0.5–4 cm.

2n

=180.

=180.

Botrychium hesperium

Botrychium paradoxum

Phenology Leaves appearing in midspring, dying in early fall.
Habitat Grassy mountain slopes, snow fields, road ditches with willows, and sand dunes Sporophores in June to August. Difficult to detect, plants usually hidden under other vegetation, in snowfields, secondary growth pastures
Elevation 200–2800 m (700–9200 ft) 1500–3000 m (4900–9800 ft)
Distribution
from FNA
AZ; CO; ID; MI; MT; UT; WY; AB; BC; ON; SK
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[BONAP county map]
from FNA
MT; UT; AB; BC; SK
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[BONAP county map]
Discussion

In the Rocky Mountains Botrychium hesperium grows often with B. echo, and in the Lake Superior region, with B. acuminatum and B. matricariifolium.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

The leaf structure of Botrychium paradoxum is uniform and unique. Very rare teratological individuals of other moonwort species may have trophophores partially or wholly transformed into sporophores.

Botrychium × watertonense W.H. Wagner, known only from one locality in western Alberta, is the sterile hybrid of B. hesperium and B. paradoxum. It can be identified by its trophophore pinnae; all are bordered with sporangia. It may reproduce by some unknown mechanism, such as unreduced spores (W.H. Wagner Jr., F. S. Wagner, et al. 1984).

Of conservation concern.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 2. FNA vol. 2.
Parent taxa Ophioglossaceae > Botrychium > subg. Botrychium Ophioglossaceae > Botrychium > subg. Botrychium
Sibling taxa
B. acuminatum, B. ascendens, B. biternatum, B. boreale, B. campestre, B. crenulatum, B. dissectum, B. echo, B. gallicomontanum, B. jenmanii, B. lanceolatum, B. lunaria, B. lunarioides, B. matricariifolium, B. minganense, B. montanum, B. mormo, B. multifidum, B. oneidense, B. pallidum, B. paradoxum, B. pedunculosum, B. pinnatum, B. pseudopinnatum, B. pumicola, B. rugulosum, B. simplex, B. spathulatum, B. virginianum
B. acuminatum, B. ascendens, B. biternatum, B. boreale, B. campestre, B. crenulatum, B. dissectum, B. echo, B. gallicomontanum, B. hesperium, B. jenmanii, B. lanceolatum, B. lunaria, B. lunarioides, B. matricariifolium, B. minganense, B. montanum, B. mormo, B. multifidum, B. oneidense, B. pallidum, B. pedunculosum, B. pinnatum, B. pseudopinnatum, B. pumicola, B. rugulosum, B. simplex, B. spathulatum, B. virginianum
Synonyms B. matricariifolium subsp. hesperium
Name authority (Maxon & R. T. Clausen) W. H. Wagner & Lellinger: Amer. Fern J. 71: 92. (1981) W. H. Wagner: Amer. Fern J. 71: 24. (1981)
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