Hesperevax acaulis var. ambusticola

Morefield

Syst. Bot. 17: 306, fig. 5A–L. 1992.

Common names: Fire evax
Endemic
Treatment appears in FNA Volume 19. Treatment on page 469.

Plants 0.5–2 (–4) cm. Stems (0–) 4–10, ± prostrate (in depauperate plants sometimes 0, or 1, erect, unbranched); branches proximal and/or distal. Leaves cauline, petiolate, largest mostly 4–7 × 1–2 mm; petiole lengths mostly 0.5–1.5 times blade lengths; blades obovate to ± round, obtuse; capitular leaves mostly distally spreading. Heads usually borne singly, largest 2–2.5 × 1.5–2 mm. Receptacles 1–1.4 × 0.8–1.1 mm. Pistillate paleae in 3–4 series, 1.7–2.5 mm. Staminate paleae: longest 1.6–2 mm. Functionally staminate florets 2–5 (–9); corollas 0.6–0.8 mm. Cypselae mostly 0.8–1 mm.


Phenology: Flowering and fruiting mostly Apr–early Jun.
Habitat: Dry or vernally moist slopes, relatively barren or in clearings, recent chaparral burns
Elevation: 200–1300 m

Discussion

Variety ambusticola is known from mountains of western Riverside County to the San Francisco Bay area and northern Sierra Nevada foothills. It occurs at about the same elevations as, and intergrades extensively with, var. robustior in northern California (J. D. Morefield 1992c).

Depauperate individuals of var. ambusticola are among the smaller and more inconspicuous Compositae, sometimes consisting of just one grayish head embedded in a leaf rosette on a root 1–2 cm long.

Selected References

None.

Lower Taxa

None.

"-1.5timesbladelengths" is not declared as a valid unit of measurement for this property.

truncate-penicillate;truncate +
scarious +
mostly ovate +  and lanceovate or linear +
spiciform +  and cymiform +
indeterminate +  and determinate +
James D. Morefield +
Morefield +
decurrent +
pliant to somewhat +
Stylocline acaulis +
compound +  and simple +
obtuse;obovate;more or less round +
5-ribbed +, 3-ribbed +  and 2-ribbed +
muriculate +, papillate +  and smooth +
obovate;obovate;oblanceolate not gibbous flat +
Fire evax +
actinomorphic +
red-tipped +, purplish +, yellow +  and whitish +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
black-banded +  and brown +
not gibbous +, obovoid +  and obcompressed +
2.2 cm22 mm <br />0.022 m <br /> (3.2 cm32 mm <br />0.032 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
largest +  and larger +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
200–1300 m +
dull +  and more or less shiny +
winged +  and beaked +
dispersed +
Dry or vernally moist slopes, relatively barren or in clearings, recent chaparral burns +
indeterminate +
1-1.5 times diams +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
homogamous +  and heterogamous +
campanulate +
largest +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
each +  and sessile +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
2 (?) +  and 8 (?) +
largest +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
rarely lanceovate +  and lanceolate +
2-carpellate +
staminate +  and pistillate +
persistent +
spreading +, erect +  and ascending or spreading +
spatulate;unlike +
0.16 cm1.6 mm <br />0.0016 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
persistent +
Flowering and fruiting mostly Apr–early Jun. +
subequal +  and unequal +
paleate +  and epaleate +
0.1 cm1 mm <br />0.001 m <br /> (0.14 cm1.4 mm <br />0.0014 m <br />) +
cylindric;conic +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
exalbuminous +
0 (?) +  and 4 (?) +
erect +  and prostrate +
4 +  and 10 +
appendaged +  and truncate +
papillate +
Evax acaulis +
Hesperevax acaulis var. ambusticola +
Hesperevax acaulis +
variety +
10 cm100 mm <br />0.1 m <br /> (20 cm200 mm <br />0.2 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (10 cm100 mm <br />0.1 m <br />) +
2 cm20 mm <br />0.02 m <br /> (4 cm40 mm <br />0.04 m <br />) +