Chorizanthe valida

S. Watson

Proc. Amer. Acad. Arts 12: 271. 1877.

Common names: Sonoma spineflower
EndemicConservation concern
Treatment appears in FNA Volume 5. Treatment on page 456. Mentioned on page 447, 448.

Plants erect to spreading, 1–3 × 1–6 dm, villous. Leaves basal or nearly so; petiole 1–3 cm; blade broadly oblanceolate, 1–2.5(–5) × 0.4–0.8(–1.2) cm, usually villous. Inflorescences with secondary branches suppressed, grayish; bracts 2, similar to proximal leaf blades only reduced, short-petiolate, becoming linear and aciculate at distal nodes, acerose, 1–3 cm × 6–10 mm, awns absent. Involucres 1, grayish, cylindric, not ventricose,3–4(–4.5) mm, with white, scarious margins between teeth, finely corrugate, thinly pubescent; teeth erect, equal, 0.3–0.7(–1) mm; awns straight, with longer ones 0.7–1.3 mm and anterior one mostly 1.3 mm, these alternating with shorter, 0.5–1(–1.2) mm ones. Flowers exserted; perianth bicolored with floral tube white and tepals white to lavender or rose, cylindric, (4–)5–6 mm, pubescent on proximal 1/2; tepals connate 1/4 their length, dimorphic, oblong, truncate and erose to denticulate, sometimes individual lobes entire, 2-lobed or even cuspidate apically, those of outer lobes longer and wider than inner ones; stamens 9, included; filaments distinct, 2–4.5 mm, glabrous; anthers pink to red or maroon, oblong, 0.6–0.8(–1) mm. Achenes light brown, lenticular-globose, 3–4.5 mm.


Phenology: Flowering Jun–Aug.
Habitat: Sandy places, coastal grassland communities
Elevation: 10-100 m

Discussion

Of conservation concern.

Chorizanthe valida may be distinguished by the highly colored involucre. The teeth and bases of awns are bright red. The awns then quickly transform to a bright ivory and this color dominates nearly the length of each awn. In the more inland populations (now extirpated), the awns observed in the old collections appear to be a straw color. It is not known if this is an artifact of age or potentially significant. Sonoma spineflower is now known only from grassy fields south of Abbott’s Lagoon in the Point Reyes area of Marin County (L. Davis and R. J. Sherman 1990, 1992). The last collection from Sonoma County was made at Sebastopol in 1907. The type, collected in 1841, apparently was gathered near Fort Ross, also in Sonoma County. This species is federally listed as endangered.

Selected References

None.

Lower Taxa

None.
... more about "Chorizanthe valida"
James L. Reveal +
S. Watson +
Sonoma spineflower +
10-100 m +
Sandy places, coastal grassland communities +
Flowering Jun–Aug. +
Proc. Amer. Acad. Arts +
Endemic +  and Conservation concern +
Chorizanthe sect. Anisogonum +, Chorizanthe sect. Eriogonellopsis +  and Chorizanthe sect. Herbaceae +
Chorizanthe valida +
Chorizanthe sect. Ptelosepala +
species +