Astragalus coahuilae M. E. Jones,

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

12. Astragalus coahuilae M. E. Jones, Rev. N.-Amer. Astragalus 256. 1923

Type:— Mexico, Coahuila, Parras Coahuila , October 1910, C. A. Purpus 4671 (Holotype: UC 145648 digital image!; isotype: 15 october 1910, C. A.Purpus 4672 E 00383727 digital image!; syntype: March 1905, C. A. Purpus 1078, RSA 0002853 digital image!).

Hamosa coahuilae (M. E. Jones) Rydb. , Bull. Torrey Bot. Club 54: 23. 1927.

Perennial. Stems 12–40 cm long, ascendant, strigose, the trichomes ascendant, incurved, up to 0.4 mm long. Stípules 1–4 mm long, clasping or semi-clasping, not connate, triangular or ovate, acuminate. Leaves 3–11 cm long, leaflets 13–27, 2–16 mm long, elliptic, oblong, lanceolate-oblong to obovate, emarginate, bicolored, dark-green and glabrate adaxially. Peduncles 3–14 cm long, straight or incurved; the racemes 1–10 cm long, lax, flowers 3–15, ascendant. Flowers pale purple, sometimes with white tones; the calyx 4.6–6.4 × 1.7–2.7 mm, campanulate, strigose, trichomes black and white mixed, the tube 3–3.8 mm long, the teeth 1.8–3 mm long, lanceolate; the banner 10–15 × 5–9 mm recurved, obovate to subelliptic; the wings 9.5–12 × 1.8–2.6 mm, linear-obovate, incurved, the claw 3–4.3 mm long, the blade 6.5–8.5 mm long, with white tones apically; the keel 6.6–9 × 2.1–3 mm, incurved, the claw 3–4 mm long, the blade 4.3–5.5 mm long. Pod 10–16 × 2.2–3.4 mm, ascendant, sessile, linear to linear-oblong or triquetrous (triangular in cross-section), narrow at base, apex abruptly beaked, sulcate dorsally, laterally flattened, the valves thin, strigulose, green, becoming ochre and stiff with age, almost imperceptibly reticulated, septum complete or almost so; ovules 10–20; seeds 2–3 mm long, brown, sometimes with purple spots, smooth.

Distribution:— Endemic to north of Mexico, Coahuila (Sierra de Parras and adjacent areas), Nuevo León (Lampazos de Naranjo), Durango (La Cieneguilla, municipality of Villa Unión) and northern Zacatecas (surroundings of San Juan de los Cedros, Municipality of Mazapil) ( Fig. 4 ).

Habitat:— Calcareous and stony clay soils; rocky limestones; clayish loam; desert flats; shallow slopes with alluvial fans; streams; arid thickets with maguey and sotol, creosote bush, shrubs with lateral and cat-claw prickles, and Jousa tree; creosote bush scrublands with maguey and Josua tree; oak-pine-maple forest; Pine-Juniper associations; arid scrublands; 1600–2000 m.

Specimens examined:—COAHUILA: 29 June 2006, Sierra de Zapalinamé , Cañón de San Lorenzo, al sureste de Slatillo, S. G. Gómez 223, J. S. García ( ANSM) ; 17 June 1972, 1.0 km southeast of San Juan de los Cedros, on road to Mazapil, M. C. Johnston 7924, F. Chiang, T. Wendt ( ANSM, MEXU, NY, SD, TEX-LL) ; 24 June 1987, Cañón de San José de los Nuncio, Ramos — Arizpe, A. Rodríguez 865, M. A. Carranza ( ANSM, CIIDIR, ENCB, MEXU) ; 21 August 1999, Sierra de la Babia , Coahuila, M. A. Carranza C-3044, T. Wendt, D. Riskind, J. Henrickson, ( ANSM, TEX-LL) ; 11 September 1963, 3 miles W of Parras , H. D. Ripley 13513, R. C. Barneby ( MEXU, NY, US) ; 8–28 June 1880, Parras , 111½ miles west of Saltillo, E. Palmer 234 ( TEX, NY, US) ; 15 October 1983, Ejido Siete de Enero aprox. 36 km al SE de Parras de la Fuente, A. Rodríguez 1072, M. A. Carranza ( CIIDIR, NY) ; X-1910, Sierra de Parras , C. A. Purpus 4672 ( US) ; 6 March 1983, Parras , A. Rodríguez 82 et al. ( ENCB). DURANGO : 7 May 1981, Villa Unión , Durango, S. González 1659, M. González ( CIIDIR). NUEVO LEÓN : 26 March 1944, Thurty six miles northeast of Sabinas Hidalgo, G. Webster 13504, F. Barkley ( US) ; 26 March 1944, Thirty-six miles northeast of Sabinas Hidalgo, F. A. Barkley 14576 ( US). ZACATECAS: 13 / 14 August 1904, Zacatecas , Near Concepción del Oro, E. Palmer 305 ( US) ; 1-X-1910, Sierra de Parras. , C. A. Purpus ( US) ; 30 August 1971, 1 mile W of Concepcion del Oro along road to the main mine J. Henrickson 6255 ( IEB, MEXU, TEX-LL) .

Figures

FIGURE 4. Map showing the distribution of Astragalus coahuilae, A. cobrensis var. maguirei, A. coccineus, A. comonduensis, and A. coriaceus in Mexico.