Heterotheca sessiliflora subsp. fastigiata

(Greene) Semple

Phytologia 73: 451. 1993.

Endemic
Basionym: Chrysopsis fastigiata Greene Pittonia 3: 296. 1898
Synonyms: Chrysopsis villosa var. fastigiata (Greene) H. M. Hall Heterotheca fastigiata (Greene) V. L. Harms Heterotheca sessiliflora var. sanjacintensis Semple
Treatment appears in FNA Volume 20. Treatment on page 238. Mentioned on page 239.

Stems 1–20, ascending to erect, (24–) 37–85 (–108) cm, densely strigose, becoming moderately hispido-strigose and densely stipitate-glandular distally. Cauline leaves sessile, light green or silvery-whitish; proximal oblanceolate 12–38 × (3–) 4.7–7 (–8.5) mm, margins entire, undulate, faces moderately to densely hispido-strigose, very sparsely to moderately stipitate-glandular; distal lanceolate, 10–20 × 2–6 mm, reduced distally, stiff, bases rounded, margins usually strongly undulate, often more stipitate-glandular and less ciliate than faces, sparsely to extremely densely short-strigose, sparsely to densely glandular. Peduncle bracts 3–5, leaflike, greatly reduced, none enlarged and subtending heads. Involucres 7–10 (–12) mm. Ray-florets 4–14; laminae 3.5–5.9 (–9) mm. Disc-florets: corolla lobes sparsely pilose, hairs 0.25–0.6 mm. Cypsela faces sparsely strigose. 2n = 18.


Phenology: Flowering Jul–Oct(–Dec) (rarely spring).
Habitat: Arroyos, embankments, in oak scrub and pine forests, rarely adventive in desert arroyos below mountains
Elevation: (100–)300–1800(–2200) m

Discussion

Subspecies fastigiata is known from the San Gabriel, San Bernardino, and San Jacinto mountains, and from Mount Palomar. It is distinguished by its undulate leaf margins, heads not subtended by large peduncle bracts, and usually low number of ray florets. Two varieties have been recognized on the basis of the density of leaf hairs and glands. In var. fastigiata, the leaves appear silvery white because of the densely short-strigoso-canescent indument of tightly appressed, short hairs obscuring underlying glands; it occurs in the San Gabriel, San Bernardino, and Santa Monica mountains. In var. sanjacintensis, the leaves are sparsely to moderately hispido-strigose and are more densely stipitate-glandular, giving them a light green appearance; it is known from the San Jacinto Mountains and Mount Palomar, and is of conservation concern. Hybridization with subsp. echioides occurs at lower elevations throughout the range.

Selected References

None.

Lower Taxa

None.

"[" is not declared as a valid unit of measurement for this property."]" is not declared as a valid unit of measurement for this property.

not tailed +, rounded +  and obtuse +
distinct +
subequal +
scarious +
usually triangular +  and linear +
usually deltate +  and lanceolate +
paniculiform +  and corymbiform +
indeterminate +  and determinate +
John C. Semple +
(Greene) Semple +
rounded +
Chrysopsis fastigiata +
compound +  and simple +
4 cm40 mm <br />0.04 m <br /> (6 cm60 mm <br />0.06 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
0.65 cm6.5 mm <br />0.0065 m <br /> (4 cm40 mm <br />0.04 m <br />) +
oblanceolate;lanceolate;oblanceolate +
reduced +
1.5mm;8mm +
rugulose +  and muricate +
leafy +  and phyllary-like +
0.85 cm8.5 mm <br />0.0085 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.85 cm8.5 mm <br />0.0085 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
barbellulate +  and barbellate +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
rhizomatous +  and taprooted +
silvery-whitish +  and light green +
not 2-lipped +  and actinomorphic +
0.7 cm7 mm <br />0.007 m <br /> (0.95 cm9.5 mm <br />0.0095 m <br />) +
glabrous +  and glabrate +
ampliate +
0.55 cm5.5 mm <br />0.0055 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
compressed +  and obconic +
fertile +  and bisexual +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (?) +  and 0.6 cm6 mm <br />0.006 m <br /> (?) +
(100–)300–1800(–2200) m +
stipitate-glandular +  and hispido-strigose +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Arroyos, embankments, in oak scrub and pine forests, rarely adventive in desert arroyos below mountains +
0.025 cm0.25 mm <br />2.5e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
paniculiform +
in corymbiform arrays +  and singly +
indeterminate +
heterogamous +  and homogamous +
lanceolate +
reduced +
each +  and sessile +
attenuate +  and weakly clavate +
tan;rusty brown +
attenuate +  and clavate +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
campanulate;turbinate;campanulate;turbinate;cylindric +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
1.05 cm10.5 mm <br />0.0105 m <br /> (1.85 cm18.5 mm <br />0.0185 m <br />) +
0.59 cm5.9 mm <br />0.0059 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
0.17 cm1.7 mm <br />0.0017 m <br /> (0.24 cm2.4 mm <br />0.0024 m <br />) +
4.5mm;10.5mm +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.59 cm5.9 mm <br />0.0059 m <br />) +
1mm;1.7mm +
sessile +  and petiolate +
proximal +  and basal +
erect;spreading +
lanceolate +, triangular +  and deltate +
more stipitate-glandular and less ciliate +
short-strigose +  and stipitate-glandular +
undulate +
2-carpellate +
in 3 +  and 4 series +
enlarged +  and reduced +
glandular +, strigose +  and hispid +
0.2 cm2 mm <br />0.002 m <br /> (10 cm100 mm <br />0.1 m <br />) +
Flowering Jul–Oct(–Dec) (rarely spring). +
lanceolate +  and linear-lanceolate +
ovate-oblanceolate +
0.7 cm7 mm <br />0.007 m <br /> (0.85 cm8.5 mm <br />0.0085 m <br />) +
1.2 cm12 mm <br />0.012 m <br /> (3.8 cm38 mm <br />0.038 m <br />) +
0.47 cm4.7 mm <br />0.0047 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
bearing subulate enations +, hairy +  and bristly +
subulate;convex +
6 +  and 10 +
3 +  and 40 +
linear +  and linear-lanceolate or triangular +
0.025 cm0.25 mm <br />2.5e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
exalbuminous +
ascending +  and erect +
1 +  and 20 +
37 cm370 mm <br />0.37 m <br /> (85 cm850 mm <br />0.85 m <br />) +
appendaged +  and truncate +
papillate +  and smooth +
Chrysopsis villosa var. fastigiata +, Heterotheca fastigiata +  and Heterotheca sessiliflora var. sanjacintensis +
Heterotheca sessiliflora subsp. fastigiata +
Heterotheca sessiliflora +
subspecies +
70 cm700 mm <br />0.7 m <br /> (110 cm1,100 mm <br />1.1 m <br />) +
20 cm200 mm <br />0.2 m <br /> (70 cm700 mm <br />0.7 m <br />) +
tree +, shrub +  and subshrub +