Astragalus legionensis Barneby,

Castillón, Eduardo Estrada, Quintanilla, José Ángel Villarreal, Delgado-Salinas, Alfonso & Rebman, Jon P., 2023, The genus Astragalus (Leguminosae: Papilionoideae: Galegeae) in Mexico, Phytotaxa 586 (1), pp. 1921-1935 : 1921-1935

50. Astragalus legionensis Barneby, Mem. New York Bot. Gard. 13: 156. 1964

Type:— MEXICO, Nuevo León, ascent to Sierra Infiernillo and Cerro El Viejo , Sierra Madre Occidental (wrong, is S. M. Oriental), 6 June 1934, C. H. & M. T. Muller 823. (holotype: MICH1107114 digital image!; isotype: TEX-LL00371238 digital image!, GH00059421 digital image!) .

Perennial. Stems dwarf, 2–7 cm long, hirsute, the trichomes up to 0.8 mm long, straight, lax ascendant. Stipules 0.6– 9.5 mm long, the lowest ones attached almost all its length, forming a triangular, bidentate sheath apically, the upper ones connate, attached almost half of its length. Leaves 1.5–6.5 cm long, leaflets 9–27, 0.8–6.5 mm long, oblong, elliptic to obovate, retuse, rarely subtruncate, adaxially glabrate or almost so. Peduncles 1–5 cm long, ascendant; the racemes 1.5–10 mm long, flowers 2–5, early ascendant or spreading but soon deflexed. Flowers purple to purple-violet; the calyx 6.2–7.9 × 2.3–3 mm, densely hirsute, mainly with black trichomes and few white ones, the tube 3.2–3.5 mm long campanulate; the teeth 2.6–4.4 mm long, lanceolate to subulate, sinus obtuse among teeth; the banner 9.2–14 × 5.6–6.2 mm, obovate to rhombic, recurved, shallowly retuse; the wings 9–12.2 × 1.8–3.5 mm, the claw 3.5–4.2 mm long, the blade 6.5–8.8 mm long, oblong, oblanceolate to obovate, incurved; the keel 7.3–8.5 × 2.2–2.5 mm, the claw 3.7–4.5 mm long, the blade 4–4.4 mm long, semi-obovate, abruptly incurved distally. Pod pendulous, stipitate (stipe 2–4 mm long) oblong to elliptic, 14–15 × 3–4.5 mm, recurved, obcompressed, dorsoventrally compressed, ventrally slightly carinate, dorsally flattened and shallow and openly grooved, the valves thin, glabrate, papery with age, ochre or black (remaninig in the peduncles of the past season) with other (in different peduncle), light brown of the present season together, septum complete, the pod thence bilocular; ovules 8–12; seeds not seen.

Distribution:— Endemic to Mexico; mountains of the state of Coahuila (Cerro La Viga, Arteaga) and Nuevo León (Cerro El Infiernillo, Galeana and Cerro El Viejo, Zaragoza) ( Fig. 14 ).

Habitat:— Rare, rocky summit; in pine-oak forest; Pinus , Quercus, Juniper forest; associations of Joshua tree, sotol, maguey, sumac; roadside; pine - douglas fir - fir association; 2000–3380 m.

Comments:— The mountainous areas and portions of the High Plains in the central region of the geopolitical border between Coahuila and Nuevo Léon, houses 13 species of Astragalus , but this species is easily separated from the others by its stipitate but flattened or obcompressed pod.

Specimens examined:—COAHUILA: 2 October 1982, On the road to the top of Cerro de la Viga, about 30 km east of Hwy 57, J. Grimes 2291, K. Nixon, S. Sundberg ( NY) ; 23 June 1985, Sierra El Coahuilón, Mpio. Arteaga, Hinton et al. 18871 ( IEB) . NUEVO LEÓN: 29 June 1934, Mt. “El Infernillo”, Pablillo, southeast of Galeana. Sierra Madre Oriental , F. W. Pennell 17125 ( US), 17130 ( NY, US) ; 18 May 1978, San Antonio Peña Nevada, Hinton 17328 ( ENCB, IEB) ; 24 March 1985, El Carrizo, G.L Nesom 18800 ( MEXU) ; 25 June 1978, Picacho San Onofre, Mpio. Zaragoza, Hinton et al. 17382 ( MEXU) .

Figures

FIGURE 14. Map showing the distribution of Astragalus insularis var. insularis, A. insularis var. hardwoodii, A. insularis var. quentinus, A. jalicensis and A. legionensis in Mexico.