Astragalus sect. Reventi-arrecti
several to many.
odd-pinnate, usually petiolate, rarely short-petiolate or subsessile;
leaflets (5 or)7–41.
loosely flowered, sometimes initially densely flowered, flowers usually ascending, spreading, or nodding, rarely declined; length of peduncle and raceme combined usually exceeding stem length, sometimes shorter.
whitish, greenish white, cream, ochroleucous, pink, or purple with pale wing apices, banner 40–90°, keel apex usually round or narrowly triangular, sometimes sharply deltate or beaklike.
tubes short-cylindric or campanulate.
persistent, sessile or stipitate, usually erect or incurved-ascending, rarely deflexed, ovoid, oblong-ovoid to ellipsoid, or linear-oblong or -oblanceoloid, obcompressed or dorsiventrally or 3-sided compressed or subterete, unilocular or ± bilocular.
14–36.
basifixed or malpighian.
distinct.
Astragalus sect. Reventi-arrecti
Species 14 (12 in the flora).
Section Reventi-arrecti consists of six subsections with distribution in the Columbia and Great basins, eastward to southwestern Montana and northwestern Wyoming, southward to southern Nevada, Arizona, and western New Mexico, and in Baja California.
The subsections are: subsect. Reventi M. E. Jones (Astragalus adanus, A. reventus, A. sheldonii); subsect. Terminales Barneby (A. terminalis); subsect. Arrecti M. E. Jones (A. arrectus, A. riparius); subsect. Eremitici Barneby (A. atropubescens, A. eremiticus, A. remotus, A. scaphoides); subsect. Orcuttiani (Rydberg) Barneby (A. ackermanii); and subsect. Obscuri Barneby (A. obscurus).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
