Hesperevax sparsiflora

(A. Gray) Greene

Fl. Francisc., 402. 1897.

Common names: Erect evax
IllustratedEndemic
Basionym: Evax caulescens var. sparsiflora A. Gray in A. Gray et al., Syn. Fl. N. Amer. 1(2): 229. 1884
Synonyms: Evax sparsiflora (A. Gray) Jepson
Treatment appears in FNA Volume 19. Treatment on page 468. Mentioned on page 467.

Plants 2–17 cm. Stems 1–10, ascending to erect (rarely 0); branches 0 or proximal. Leaves mostly cauline, petiolate, distal scarcely congested, ± equal to proximal, largest 6–32 × 3–8(–10) mm; petioles: lengths 0.9–1.5 times blade lengths, bases thickened, cartilaginous to ± indurate; capitular leaves 1–4 per glomerule or head, approximate, not whorled, ascending to erect, some sometimes grading into pistillate paleae (by reduction of blades, expansion of petiole bases). Heads terminal in loose glomerules (3–4 mm diam.) of 3–5 mixed with leaves and some borne singly in axils, cylindric, 3–4.5 × 1.5–2 mm, heights 1.8–2.5 times diams. Receptacles distinct, 1.4–1.8 × 0.2–0.4 mm. Pistillate paleae in 1–3 series, spirally ranked, oblanceolate, 2.5–4.5 mm. Staminate paleae not or scarcely surpassing pistillate, 1.1–1.8 mm, lengths 0.3–0.4 times head heights; apices ± erect. Functionally staminate florets 2–5; corollas 0.8–1.1 mm. Cypselae mostly 1–1.7 mm.

Discussion

Varieties 2 (2 in the flora).

The varieties of Hesperevax sparsiflora occur in distinct habitats and might be treated as separate species but for some morphologically intermediate specimens from areas of sympatry in the San Francisco Bay area.

Selected References

None.

Key

1 Largest leaves (10–)13–32 × 4–8(–10) mm, blades broadly oblanceolate to obovate, arachnoid-seri- ceous Hesperevax sparsiflora var. sparsiflora
1 Largest leaves 6–12(–14) × 3–5(–6) mm, blades ± round, ± densely lanuginose Hesperevax sparsiflora var. brevifolia