Astragalus hintonii Barneby var. hintonii

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

42.2. Astragalus hintonii Barneby var. hintonii

Type:— MEXICO, Michoacán, ascent of Cerro Pelón from Zitacuaro , distr. Zitacuaro , 3600m, 14 September 1938, G. B. Hinton 13240 (holotype: NY 00005802 !; isotype: TEX-LL00371235 !, GBH 013240 digital image!, K 000118207 digital image!, P 00585371 digital image!, US 00004124, UC 1113910 digital image!, S-G-10224 digital image!) .

Astragalus hintonii Barneby, Mem. New York Bot. Gard. 13(1): 156–157. 1964.

Main differences as in key. Stems buried, short, up to 19 cm long; stipules of different size, the upper one the longer, the lowest ones the shorter and wider, forming a lax sheath; peduncles up to 5.3 cm long; the calyx with mixed black and white trichomes; the banner short, 11–13 mm long.

Distribution:— Endemic to southern Mexico; mountains of Michoacán (between Zitácuaro-Cerro Pelón and Cerro San Andrés), rare ( Fig. 12 ).

Habitat:— Paddocks; roadside; hillsides; fir forest; flooded grasslands; subalpine grassland with pine; pine forest; juniper scrubland; pine - fir forest; 2940–3589 m.

Comments:— In this region, there are other two species with tumescent (bulged), dorsoventrally flattened, oblong to elliptic and stipitate pod, A. guatemalensis var. brevidentatus , and A. strigulosus , this last one with white petals; while A. g. var. brevidentatus shows shorter (calyx 3.2–6 mm, wings 8–10.5 mm, and keel 6.8–8.3 mm) and more amount of flowers, averaging 20–30 flowers per raceme, and slightly larger pod (21 mm).

Specimens examined:— MICHOACÁN: 14 September 1938, Distrito Zitacuaro. Alt. 3600 m, G. B. Hinton 13240 (NY, TEX-LL); 6 September 1960, Summit of Cerro San Andres, ca. 12 kms (straigh line distance) north of Ciudad Hidalgo, J. H. Beaman 4299 (NY); 16 October 1991, Cerro La Taza, Mpio. Huiramba, E. García et al. 3965 (IEB); 2 August 2001, Angangueo, Sierra Chincua, M. G. Cornejo T. 263, G. Ibarra M. (IEB, MEXU); 27 August 1986, 300 m ESE del Pozo Az-9, Campo Geotérmico “Los Azufres”, Mpio. Zinapécuaro, E. Carranza G. 355 (IEB); 29 August 1987, parte alta del Cerro San Andrés, S. Zamudio R. 5559 (IEB, MEXU); 13 July 1991, Laguna de San gregorio, Mpio. Santa Clara del Cobre, J. M. Escobedo 1947 (IEB); 7 August 2010, Ladera W de la cima del Cerro San Andres, Mpio., Ciudad Hidalgo, G. Aguilar G. 66, S. Zamudio, J. J. Von Taden, H. Von Taden (IEB); 22 September 1988, Prersa Pízcuaro, Mpio. Zinapécuaro, M. J. Jasso 166 (IEB); 17 September 1995, Llano Las Papas, Mpio. Angangueo, Rzedoswki 53773 (IEB); 27 June 2012, Cima del Cerro San Andres, ladera W, Mpio. Cd. Hidalgo, G. Aguilar A. 881, S. Zamudio (IEB); 4 August 1994, Alrededores de la Presa Llano Grande, al E de Los Azufres, E. Carranza 4821 (ENCB, IEB, MEXU); 6 September 1987, La Lagunita, cerca de San Gregorio, Mpio. Santa Clara del Cobre, Rzedowski 44638 (IEB); 8 September 1987, Llano Largo, cerca de Los Azufres, Mpio. Zinapécuaro, H. Díaz B. 3935 (IEB); 7 July 1989, Presa la Gachupina, lado SW, M. J. Jasso T. 1599 (ENCB, IEB, MEXU); 7 July 1989, Llano Los Ajolotes, Los Azufres, M. J. Jasso T. 1227 (ENCB, IEB, MEXU); 27 June 2012, Cima del Cerro San Andrés, 1 776 m al SW de las antenas, Mpio. Ciudad Hidalgo, G. Aguilar A. 904, S. Zamudio (IEB).

Figures

FIGURE 12. Map showing the distribution of Astragalus hintonii var. hintonii, A. hintonii var. cofrensis, A. hornii var. minutiflorus, A. humistratus var. humistratus, and A. humistratus var. sonorae in Mexico.