Pellaea glabella subsp. occidentalis

(E. E. Nelson) Windham

Contr. Univ. Michigan Herb. 19: 39. 1993.

Endemic
Basionym: Pellaea atropurpurea var. occidentalis E. E. Nelson Fern Bull. 7: 30. 1899
Synonyms: Pellaea glabella var. nana (Richardson) Cody Pellaea glabella var. occidentalis (E. E. Nelson) Butters Pellaea occidentalis Pellaea pumila
Treatment appears in FNA Volume 2.

Ultimate segments glabrous; sporangia containing 64 spores; spores averaging 38–52 µm diam. 2n = 58.


Phenology: Sporulating summer–fall.
Habitat: Calcareous cliffs and ledges, usually on limestone
Elevation: 500–2800 m

Distribution

V2 625-distribution-map.gif

Man., Sask., Mont., N.Dak., S.Dak., Utah, Wyo.

Discussion

Most recent treatments refer to this taxon as Pellaea glabella var. occidentalis. It appears to be synonymous, however, with P. glabella var. nana, which was proposed 76 years earlier and has priority if the taxon is treated at varietal rank. This diploid (treated here as a subspecies) often shows prominent articulation lines near the base of the petiole, and plants with less divided leaves are occasionally misidentified as P. breweri. At least some of the sporangia of subsp. occidentalis are long-stalked, however, whereas those of P. breweri are sessile or subsessile.

Selected References

None.

Lower Taxa

None.
Michael D. Windham +
(E. E. Nelson) Windham +
cordate +, truncate +  and rounded +
Pellaea atropurpurea var. occidentalis +
glabrous +  and pubescent +
linear-oblong +  and ovatelanceolate +
1cm;8cm +
erose-denticulate +
straight +
Man. +, Sask. +, Mont. +, N.Dak. +, S.Dak. +, Utah +  and Wyo. +
500–2800 m +
yellow +  and white +
obcordate;reniform +
Calcareous cliffs and ledges, usually on limestone +
monomorphic +
clustered;widely scattered +
recurved +  and reflexed +
noncircinate +  and circinate +
2 cm20 mm <br />0.02 m <br /> (40 cm400 mm <br />0.4 m <br />) +
? (?) +  and ? (?) +
entire +, erose +  and dentate +
entire +  and denticulate +
pubescent +  and glabrous +
Sporulating summer–fall. +
Contr. Univ. Michigan Herb. +
reddish-brown +
persistent +
occasional +
hairlike +  and linear-subulate +
thin +, 0.1mm +  and 0.3mm +
brown +  and tan +
cristate +  and tetrahedral-globose +
dark colored +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Pellaea glabella var. nana +, Pellaea glabella var. occidentalis +, Pellaea occidentalis +  and Pellaea pumila +
Pellaea glabella subsp. occidentalis +
Pellaea glabella +
subspecies +
0.5 cm5 mm <br />0.005 m <br /> (2 cm20 mm <br />0.02 m <br />) +
leathery +  and herbaceous +
crescent--shaped +  and roundish +
branched +  and anastomosing +