Delphinium subsect. Echinata
Bot. Zhurn. (Moscow & Leningrad) 72: 689. 1987.
Roots 3-9(-20)-branched, 3-8(-30) cm, fascicled, dry to fleshy, ± succulent, thin threadlike segments restricted to termini of major segment; buds minute. Stems 1(-2) per root, unbranched, elongation delayed 2-10 weeks after leaf initiation; base usually not narrowed, firmly attached to root; proximal internodes much shorter than those of midstem. Leaves basal and cauline, largest near base of stem, others often abruptly smaller on distal portion of stem; basal petioles spreading, cauline petioles ascending; blades of basal leaves more rounded and with fewer, wider lobes than cauline leaves. Inflorescences usually with 2-11 flowers per 5 cm, dense to open, cylindric, spurs rarely intersecting rachis; pedicel ascending, usually less than 2 cm, rachis to midpedicel angle more than 30°; bracts markedly smaller and fewer lobed than leaves. Fruits erect. Seeds ± rectangular, 1.5-2.5 × 0.8-1.5 mm, not ringed at proximal end, ± wing-margined; seed coats without wavy ridges (sometimes with prism-shaped structures in D. hansenii), cells ± brick-shaped, cell margins straight or undulate.
Species 4 (4 in the flora).
|1||Proximal petioles glabrous to puberulent with short (less than 0.5 mm) appressed and/or arched hairs.||> 2|
|1||Proximal petioles with long (more than 0.5 mm), straight spreading hairs.||> 3|
|2||Sepal color and/or stem pubescence different from that of other individuals with which they occur; stem base puberulent with short arched hairs.||Delphinium hesperium subsp. pallescens|
|2||Sepal color and stem pubescence similar to that of other individuals with which they occur; stem base glabrous to pubescent with short straight hairs.||Delphinium hesperium|
|3||Seeds echinate, appearing fuzzy to naked eye; lateral sepals 13 mm or shorter; flowers usually more than 12 per main inflorescence branch.||Delphinium hansenii|
|3||Seeds not echinate, appearing ± smooth to naked eye; lateral sepals 10 mm or longer; flowers usually fewer than 12 per main inflorescence branch.||> 4|
|4||Stem base longitudinally ridged.||Delphinium hesperium|
|4||Stem base not longitudinally ridged.||> 5|
|5||Margins of lower petals ciliate; bracteoles usually 7 mm or less from sepals; sepal spur straight.||Delphinium variegatum|
|5||Margins of lower petals glabrous; bracteoles usually 7 mm or more from sepals; sepal spur often downcurved for more than 3 mm at apex.||Delphinium hutchinsoniae|