Pseudognaphalium saxicola

(Fassett) H. E. Ballard & Feller

Sida 21: 777. 2004.

Common names: Cliff cudweed
Endemic
Basionym: Gnaphalium saxicola Fassett Rhodora 33: 75. 1931
Synonyms: Gnaphalium obtusifolium var. saxicola (Fassett) Cronquist Pseudognaphalium obtusifolium var. saxicola (Fassett) Kartesz
Treatment appears in FNA Volume 19. Treatment on page 420. Mentioned on page 415, 417, 421.

Annuals, 4–15 (–30) cm; taprooted. Stems (filiform) persistently tomentose (indument a loose, envelope-like, transparent haze of extremely thin hairs, doubling apparent stem width), not glandular. Leaf-blades elliptic-oblanceolate to oblanceolate, 0.5–3 cm × 2–6 mm (largest at midstem), bases not clasping, not decurrent, margins flat, faces concolor, green, thinly arachnoid-tomentose to glabrate, not glandular (veiny reticulum evident). Heads (2–4) in terminal, capitate clusters (usually immediately subtended by distalmost cauline leaf, clusters sometimes in subcorymbiform arrays). Involucres turbinate, 4–5 mm. Phyllaries in 3 (–4) series, whitish to slightly tawny (hyaline, shiny), narrowly triangular to narrowly oblong-triangular, glabrous. Pistillate florets 25–28. Bisexual florets 6–7. Cypselae not ridged, smooth.


Phenology: Flowering (Jul–)Aug–Sep.
Habitat: Mostly bare sandstone cliff faces, ledges, and cracks, s- to e-facing, commonly shaded
Elevation: 200–300 m

Discussion

Pseudognaphalium saxicola probably is an evolutionary derivative of P. obtusifolium. Plants of P. saxicola are relatively small and have relatively few, relatively small heads and occur in a specialized habitat; they constitute the only narrowly endemic species of Pseudognaphalium in the United States. Depauperate individuals of P. obtusifolium from localities over its whole geographic range may sometimes be as short as 5–10 cm and similar in habit to P. saxicola; such plants differ from P. saxicola in their close and denser stem vestiture, bicolor and relatively narrow leaves, larger heads with greater numbers of pistillate florets, and broader phyllaries with rounded apices.

Selected References

None.

Lower Taxa

None.
... more about "Pseudognaphalium saxicola"
white +  and gray +
tomentose +  and velutinous +
grayish;greenish +
arachnose +, glabrescent +  and glabrous +
truncate-penicillate;truncate +
scarious +
mostly ovate +  and lanceovate or linear +
paniculiform +  and corymbiform +
indeterminate +  and determinate +
Guy L. Nesom +
(Fassett) H. E. Ballard & Feller +
not decurrent +
Gnaphalium saxicola +
compound +  and simple +
mostly narrowly lanceolate;oblanceolate +
5-ribbed +, 3-ribbed +  and 2-ribbed +
muriculate +, papillate +  and smooth +
Cliff cudweed +
actinomorphic +
not ridged +
200–300 m +
green;concolor +
thinly arachnoid-tomentose +  and glabrate +
papillate-roughened +
winged +  and beaked +
dispersed +
Mostly bare sandstone cliff faces, ledges, and cracks, s- to e-facing, commonly shaded +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (3 cm30 mm <br />0.03 m <br />) +
elliptic-oblanceolate;oblanceolate +
cauline +  and basal +
rarely lanceovate +  and lanceolate +
2-carpellate +
persistent +
Flowering (Jul–)Aug–Sep. +
bearing subulate enations +, hairy +  and bristly +
conic;more or less columnar +
4 +  and 6 +
exalbuminous +
decumbent +  and procumbent +
appendaged +  and truncate +
papillate +
Gnaphalium obtusifolium var. saxicola +  and Pseudognaphalium obtusifolium var. saxicola +
Pseudognaphalium saxicola +
Pseudognaphalium +
species +
15 cm150 mm <br />0.15 m <br /> (30 cm300 mm <br />0.3 m <br />) +
4 cm40 mm <br />0.04 m <br /> (15 cm150 mm <br />0.15 m <br />) +
shrub +  and subshrub +