Astragalus minthorniae
Fl. Calif. 2: 374. 1936.
Plants 8–40 cm, strigulose or villosulous; from superficial caudex. Stems few or several, ascending to erect, proximalmost internodes very short, strigulose or villosulous. Leaves (4–)6–17 cm; stipules obscuring proximal internodes, 3–11 mm, papery-membranous at proximal nodes, subherbaceous at distal nodes; leaflets (7 or)9–17, blades obovate, lanceolate, or broadly elliptic to suborbiculate, 8–20(–26) mm, apex obtuse to emarginate, surfaces strigose or sparsely so abaxially, strigose, glabrous, or glabrescent adaxially. Peduncles erect, 6–16 cm, together with racemes usually longer than leaves, often sub-basal and appearing scapelike. Racemes 7–35-flowered, flowers ascending to declined; axis 2.5–14(–25) cm in fruit; bracts 2–6 mm; bracteoles 0–2. Pedicels 1–3.5 mm. Flowers 12–17(–18) mm; calyx short-cylindric, 6–7.8 mm, black-pilosulous, tube 4.5–5.2 mm, lobes subulate, 1.2–2.7 mm; corolla ochroleucous with keel tip dull purple, banner sometimes suffused with lavender, or pink-purple and wing tips pale or white; keel 9.5–13 mm. Legumes persisting on receptacle until well after maturity, falling while still attached to pedicel, erect to ascending, straight or slightly incurved, narrowly oblong, subterete, laterally compressed when pressed, not grooved ventrally, 15–26(–30) × 4–6 mm, ± bilocular, fleshy becoming leathery, silky-pilose or villous, hairs 1+ mm; septum 2.5–3.5(–4) mm wide; stipe 0.5–1.5 mm. Seeds 24–36.
Distribution
w United States.
Discussion
Varieties 2 (2 in the flora).
The closest relative of Astragalus minthorniae is apparently the south-central Utah endemic A. malacoides, which has similar but strongly curved and stipitate fruits, and larger flowers.
Selected References
None.
Key
| 1 | Herbage sparsely strigulose, hairs appressed or subappressed, to 0.7(–1) mm; basal internodes and stipules sparsely pubescent, not conspicuously more so than stem distally; s Calcareous and e Tonopah mountains in n Clarke, Lincoln, nw Nye, and s White Pine counties, Nevada. | Astragalus minthorniae var. minthorniae |
| 1 | Herbage villosulous, hairs spreading, to 0.8–1.5 mm; basal internodes and stipules densely and canescently villous-pilose, usually more densely so than stems distally; e, c Mojave Desert and Death Valley regions, se California and adjoining Nevada. | Astragalus minthorniae var. villosus |