Authors:
Similar in habit and appearance to A. arnottianus, which it replaces from the Andean lake and volcanic region southwards, but distinguished by the hairless faces of its leadets, the sometimes shortly bristled pods and, in the typical variety, by having the wings of the 1-1.3cm corolla never much longer than the keel. Flowering during summer in the wild. The wings of A.p. var. grandiflora are conspicuously longer than the keel, the larger flowers 1.3-1.5cm long are borne in greater numbers per head (up to eleven), and the leaflets average twice as many. Alpine steppe, dry dwarf pastures and open sandy places from sea level to 1700m. The distinctive red-mottled indated pods are particularly attractive.
