Castilleja densiflora var. obispoënsis

(D. D. Keck) J. M. Egger

Phytologia 90: 69. 2008.

Common names: San Luis Obispo owl’s-clover
EndemicConservation concern
Basionym: Orthocarpus densiflorus var. obispoënsis D. D. Keck Proc. Calif. Acad. Sci., ser. 4, 16: 539. 1927
Synonyms: Castilleja densiflora subsp. obispoënsis (D. D. Keck) T. I. Chuang & Heckard
Treatment appears in FNA Volume 17. Treatment on page 602. Mentioned on page 601, 603.

Herbs 0.7–1.2 dm. Stems: hairs spreading, medium length, ± stiff. Leaves linear-lanceolate, 1.4–6 cm, 0(–5)-lobed. Inflorescences 1.5–7 cm; bracts distally white on apices, rarely pale yellow. Calyces (8–)15–20 mm; abaxial clefts 7–10.5 mm, adaxial 12 mm, abaxial 33–50% of calyx length, adaxial ca. 50% of calyx length, all 4 clefts subequal, lateral 5–7 mm, 33% of calyx length. Corollas 14–22 mm; beak adaxially white, aging light pink; abaxial lip proximally creamy white or yellow-green (becoming light pink with age), distally yellow (becoming orange with age), with small purple spot, pouches appearing moderately inflated, widened gradually, longer than deep, deeply pouched (less so than var. gracilis), 4.5–7 mm.

Phenology: Flowering Apr–May.
Habitat: Coastal grasslands, springs, roadsides, pastures.
Elevation: 0–500 m.


Variety obispoënsis is white-bracted and is mostly limited to the coastal plain in San Luis Obispo County, where it is threatened by development. It can resemble Castilleja attenuata, but the spikes of var. obispoënsis are considerably wider, and the abaxial lip of the corolla is more inflated and conspicuous.

Selected References


Lower Taxa

J. Mark Egger +, Peter F. Zika +, Barbara L. Wilson +, Richard E. Brainerd +  and Nick Otting +
(D. D. Keck) J. M. Egger +
Orthocarpus densiflorus var. obispoënsis +
San Luis Obispo owl’s-clover +
0–500 m. +
Coastal grasslands, springs, roadsides, pastures. +
Flowering Apr–May. +
Endemic +  and Conservation concern +
Castilleja densiflora subsp. obispoënsis +
Castilleja densiflora var. obispoënsis +
Castilleja densiflora +
variety +