Astragalus mollissimus var. Coryi

  • Title

    Astragalus mollissimus var. Coryi

  • Authors

    Rupert C. Barneby

  • Scientific Name

    Astragalus mollissimus var. coryi Tidestr.

  • Description

    233b.  Astragalus mollissimus var. Coryi

    Habit and vesture of var. mollissimus, the stems 2-25 cm. long, the longer, spirally twisted hairs up to 1.6-2.8 mm. long; stipules triangular-acuminate or lance-caudate, (5) 7-15 mm. long; leaves (4) 6-20 cm. long, with (11) 17-25 (29) obovate or oblong-oval and obtuse, or rhombic-obovate and subacute leaflets 5-18 mm long; peduncles 8-21 cm. long; racemes densely 15-45-flowered, the axis 3.5-9 cm. long in fruit; calyx 10.5-14 mm. long, the cylindric or subcylindric tube 7-8 7 long, 3-4 mm. in diameter, the teeth (3.3) 3.7-5.5 mm. long; petals cream-colored, immaculate; banner (14.4) 15-20.3 mm. long, (5.9) 6.5-9.6 mm. wide; wings (13) 13.7-19.7 mm. long, the claws (6.8) 7.5-10.5 mm., the blades 7.3-10.7 mm. long, 1.7-2.8 mm. wide; keel 12-17.4 mm. long, the claws (6.6) 6.9-10.2 mm., the blades 6—7.9 mm. long, 2.6—3.3 mm. wide; pod narrowly ovoid or oblong-ellipsoid, 1—1.7 cm. long, 4.5—7 mm. in diameter, glabrous or thinly hispidulous distally, the beak unilocular.—Collections: 19 (o); representative: Cory 50 (GH), 56 (NY), 59 (NY), 114 (MO), 12,457 (TEX), 39,172 (TEX, topotypus), 41,447 (NY), 53,399 (SMU, SRSC, WS); Parks & Cory 28,755 (SMU), 28,760 (TEX); J. Reverchon 1281 (NY, MO).

    Calcareous clay flats and depressions on rolling plains, locally plentiful in a small area of the Edwards Plateau, between the lower Pecos and upper Concho Rivers, in Sterling, Reagan, Upton, and Crockett Counties, Texas.—Map No. 97. —March to May, sometimes again after summer or fall rains.

    Astragalus mollissimus var. Coryi (Victor Louis Cory, 1880- ) Tidest. in Proc. Biol. Soc. Wash. 50: 21. 1937, based on A. argillophilus (delighting in clay soils) Cory in Rhodora 32: 5. 1930.—"The Type specimen, No. 134, was collected May 5, 1929, from a northern tributary of Bates Draw at a point six miles north of Big Lake in Reagan County, Texas. -—Holotypus, not examined, TAES; a topotypus, and many collections distributed by Cory himself, are decisive.

    Cory’s woolly locoweed is excessively close to var. mollissimus, apparently differing only in the petal-color, although this is constant, and correlated with a disjunct dispersal. The flowers of var. Coryi are on the average a trifle smaller, and the pods somewhat more plumply ovoid in outline than those of var. mollissimus, but there is a wide overlap in all measurements.

    The first collection of var. Coryi (Reverchon 1281 from the upper Concho River) was referred by Rydberg (1930, p. 540) to A. giganteus; and Jones (1930, p. 27) made the same error when he encountered it near Ozona (Jones 26075, CAS, MO). Resembling var. Coryi superficially in its ochroleucous flowers and glabrous fruit, A. giganteus is easily distinguished by its few, stiffly erect stems, retrorsely imbricated, nodding flowers, and fruit securely attached to the receptacle until long after dehiscence. Moreover, it is a plant of streamsides in xeric pine forest, flowering in summer rather than in spring, and is known in Texas only from the Davis Mountains.