Skip to main content Skip to main navigation menu Skip to site footer
Type: Monograph
Published: 2023-03-07
Page range: 1–162
Abstract views: 29
PDF downloaded: 38

The genus Astragalus (Leguminosae: Papilionoideae: Galegeae) in Mexico

Universidad Autónoma de Nuevo León, Facultad de Ciencias Forestales, A. P. 41, 67700, Linares, Nuevo León, Mexico
Universidad Autónoma Agraria Antonio Narro, Departamento de Botánica, Saltillo, Coahuila, Mexico
Universidad Nacional Autónoma de México, Instituto de Biología, 21068
San Diego Natural History Museum, P.O. Box 121390, San Diego, California, 92112
Eudicots Fabaceae Galegeae Astragalus Mexico taxonomy


Astragalus is the most diverse genus within flowering plants with almost 2500 species, it is widely distributed around the world, very abundant in temperate regions of the Northern Hemisphere, in central and western Asia, Turkey, Iran, and Afghanistan, central Asia, Europe, Mongolia, Siberia, northeastern China, and Japan. In the American continent it is especially abundant in Canada, western United States, Mexico, and South America. Given the diversity of Astragalus species present in Mexico, the recent description of at least 15 new species for this country, the absence of a recent study that encompasses all the new findings and that the last general study for Mexico dates back almost 60 years, we consider necessary a new taxonomic synopsis that encompasses all the new information, which is presented here. The study records 102 species of Astragalus in Mexico. This work is based essentially on the review of collections of specimen samples, type specimens in national and foreign herbaria, data bases, and the collection of specimens of this genus by the authors in the last 40 years and that covers practically the entire area where this genus is distributed in Mexico. In this study we recorded 102 species and 46 infraspecific taxa; seventy one species and 17 varieties are endemic to Mexico. Baja California (32), Chihuahua (25), Durango (23), Sonora (22), Coahuila (20), San Luis Potosí (17), Nuevo León (17), and Zacatecas (15) are the states with the greatest species richness. In Mexico, the diversity of Astragalus species decreases from north to south and from west to east. Most of the species of Astragalus in Mexico are distributed in the mountains, followed by low and arid plains, including coastal dunes, those last ones, exclusively of the northwestern region. There are no records of any Astragalus species in Campeche, Tabasco, Quintana Roo or Yucatan. The dichotomous keys are based mainly on the color of flowers, the shape of the pod and if the fruit is sessile or stipitate. For each species is included also a morphological description, habitat, altitudinal range, and distribution map.


<p>Amiri, M.S., Joharchi, M.R., Nadaf, M. &amp; Nasseh, Y. (2020) Ethnobotanical knowledge of <em>Astragalus</em> spp.: The world’s largest genus of vascular plants. <em>Avicenna Journal of Phytomedicine</em> 10 (2): 128–142.</p>
<p>Anderson, D.M.W. (1989) Evidence for the safety of gum tragacanth (Asiatic Astragalus spp.) and modern criteria for the evaluation of food additives. <em>Food additives and contaminants</em> 6 (1): 1–12.&nbsp;</p>
<p>Azani, N., Bruneau, A., Wojciechowski, M.F. &amp; Zarre, S. (2017) Molecular phylogenetics of annual <em>Astragalus</em> (Fabaceae) and its systematic implications. <em>Botanical Journal of the Linnean Society</em> 184 (3): 347–365.&nbsp;</p>
<p>Barneby, R.C. (1953) Pugillus astragalorum XV: Four new species. <em>Leaflets of Western Botany </em>7 (2): 31–38</p>
<p>Barneby, R.C. (1964) Atlas of North American <em>Astragalus</em>. <em>Memoirs of the New York Botanical Garden</em> 13: 1–1188.&nbsp;</p>
<p>Barneby, R.C. (1976) Dragma hippomanicum II. Astragali novi peninsulares Moraniani. <em>Brittonia</em> 28: 273–280.&nbsp;</p>
<p>Barneby, R.C. (1982) Dragma Hippomanicum VIII. A new species of Astragalus section Strigulosi (Leguminosae) from Oaxaca. <em>Brittonia</em> 34: 78–80.</p>
<p>Barneby, R.C. (1989) <em>Intermountain Flora</em> <em>(Fabales)</em>. Vol. 3, Part B. The New York Botanical Garden, 279 pp.&nbsp;</p>
<p>Bunge, A. (1868) Generis Astragali species gerontogeae. <em>Mémoires de l’Académie impériale des sciences de St. Pétersbourg</em> 11: 1–140.</p>
<p>Camazine, S. &amp; Bye, R.A. (1980) A study of the medical ethnobotany of the Zuni Indians of New Mexico. <em>Journal of Ethnopharmacology</em> 2: 365–388.&nbsp;</p>
<p>Cavanilles, A.J. (1791) <em>Astragalus garbancillo. Icones et Descriptiones Plantarum</em> 1: 59.</p>
<p>Chaudhary, L.B., Rana, T.S. &amp; Anand, K.K. (2008) Current Status of the Systematics of Astragalus L. (Fabaceae) with Special Reference to the Himalayan Species in India. <em>Taiwania</em> 53 (4): 338–355.</p>
<p>Correll, D.S. &amp; Johnston, M.C. (1970) <em>Manual of the Vascular Plants of Texas</em>. Texas Research Foundation, Renner, Texas, 1881 pp.&nbsp;</p>
<p>Dexter, D.F., Martin, K. &amp; Travis, L. (2014) Prehistoric Plant Use at Beaver Creek Rock Shelter, Southwestern Montana, USA. <em>Ethnobotany Research and Applications</em> 12: 355–384.&nbsp;</p>
<p>de Candolle, A.P. (1802) <em>Astragalogia, nempe astragali, biser–rulae et oxytropidis: nec non phacae, colutae et lessertiae his–toria iconibus illustrate</em>. J.B. Garnery, Paris.</p>
<p>Dasgupta, A. (2019)<em> Antiinflammatory Herbal Supplements</em>. <em>Translational Inflammation Perspectives in Translational Cell Biology</em>: 69–91.&nbsp;</p>
<p>Douglas, D. (1831) <em>Astragalus lentiginosus, Fl. Bor.-Amer. </em>(Hooker) 1 (3): 151.</p>
<p>Ebrahimzadeh, H., Niknam, V. &amp; Maassoumi, A.A. (2000) Mucilage content and its sugar composition in <em>Astragalus</em> species from Iran. <em>Pakistan Journal of Botany</em> 32: 131–140.</p>
<p>Estrada, E., Villarreal, J.A. &amp; Yen, M.C. (2005) <em>Astragalus mario–sousae</em> (Fabaceae: Galegeae) a new species from northeastern Mexico. <em>Brittonia</em> 57 (4): 314–319.&nbsp;[0314:AMFGAN]2.0.CO;2</p>
<p>Estrada, E. &amp; Villarreal, J.A. (2010) Flora del centro del estado de Chihuahua, México. <em>Acta Botanica Mexicana</em> 92: 51–118.</p>
<p>Estrada, E., Delgado-Salinas, A. &amp; Villarreal-Quintanilla, J.A. (2014) <em>Leguminosas de Nuevo León, México</em>. Universidad Nacional Autónoma de México, Instituto de Biología, México, 307 pp.</p>
<p>Estrada, E., González Elizondo, S. &amp; Villarreal, J.A. (2016) A new species of <em>Astragalus</em> (Fabaceae, Faboideae) from Durango, Mexico. <em>Phytotaxa</em> 288 (1): 91–95.&nbsp;</p>
<p>Estrada, E., Rebman, J.P. &amp; Villarreal, J.A. (2019) <em>Astragalus comonduensis</em> and <em>Calliandra pilocarpa</em> (Fabaceae), two new species from Baja California Sur, Mexico. <em>Phytotaxa</em> 391 (1): 57–68.&nbsp;</p>
<p>Estrada, A.E., Villarreal, J.A. &amp; Encina, J.A. (2020) A new species and a new section of <em>Astragalus</em> (Fabaceae: Papilionoideae) from Mexico. <em>Phytotaxa</em> 428 (3): 163–172.&nbsp;</p>
<p>Estrada, A.E., Villarreal, J.A. &amp; Delgado-Salinas, A. (2022) Morphological range changes in Mexican <em>Astragalus</em> <em>radicans</em> Hornem. (Fabaceae: Galegeae): review of its taxonomy and nomenclature, <em>Phytotaxa</em> 470 (2): 123–132.&nbsp;</p>
<p>Estrada, A.E., Rebman, J., González, C. &amp; Villarreal, J.A. (2022) <em>Astragalus tijuanensis</em> and <em>Astragalus brauntonii</em> var. <em>lativexillum</em>, a new species and a new variety in the genus <em>Astragalus</em> (Fabaceae) from extreme northwestern Baja California, Mexico. <em>Phytotaxa</em> 577 (1): 1–13.&nbsp;</p>
<p>Gómez–Sosa, E. (1979) Las especies Sudamericanas del genero <em>Astragalus</em> (Leguminosae) I. Las especies Patagónicas Argentinas. <em>Darwiniana</em> 22: 313–376.</p>
<p>Goncharov, N.F., Borisova, A.G., Gorshkova, S.G., Popov, M.G. &amp; Vasilchenko, I.T. (1965) Leguminosae: <em>Astragalus</em>. <em>In</em>: Komarov, V.L. &amp; Shishkin, B.K. (Eds.) <em>Flora of the US.S.R</em>., vol. 12. Israel Program for Scientific Translations, Jerusalem, Smithsonian Institution and the National Science Foundation, Washington, D.C., pp. 1–918.</p>
<p>Graham, D., Creamer, R., Cook, D., Welch, K.D., Pfister, J., Panter, K., Cibils, A., Ralphs, M., Encinias, M., McDaniel, K., Tompson, D. &amp; Gardner, K. (2009) Solutions to locowed poisoning in New Mexico and western United States. <em>Rangelands</em> 31 (6): 3–8.&nbsp;</p>
<p>Gray, A. (1864) A revision and arrangement (mainly by the fruit) of the North American species of Astragalus and Oxytropis. <em>Proceedings of the American Academy of Arts and Sciences</em> 6: 188–236.</p>
<p>Gray, A. (1878) <em>Astragalus amphioxys</em> A. Gray. <em>Proceedings of the American Academy of Arts and Sciences</em> 13: 366–367.</p>
<p>Greene, E.L. (1885) <em>Astragalus anemophilus</em> Greene. <em>Bulletin of the Southern California Academy of Sciences</em> 1 (4): 186.</p>
<p>Greene, E.L. (1888) <em>Astragalus magdalenae</em> Greene, <em>Pittonia </em>1: 162.</p>
<p>Henrickson, J. &amp; Johnston, M.C. (1997) (prepublication) <em>A flora of the Chihuahuan Desert Region</em>. Published by J. Henrickson, Los Angeles, California, 1687 pp. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</p>
<p>Isely, D. (1998) <em>Native and naturalized Leguminosae (Fabaceae) of the United States</em>. Brigham Young University Press, Provo, 1007 pp.</p>
<p>IUCN (2022) The IUCN Red List of Threatened Species. Version 2022–1. Available from: (accessed 15 August 2022)</p>
<p>Johnston, I.M. (1947) Astragalus in Argentina, Bolivia and Chile. <em>Journal of the Arnold Arboretum</em> 28: 336–409.&nbsp;</p>
<p>Johnston, M.C. (1997) (prepublication) <em>A flora of the Chihuahuan Desert Region</em>. Published by J. Henrickson, Los Angeles, California. 1687 pp. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</p>
<p>Jones, M.E. (1893) <em>Astragalus proriferus</em> M. E. Jones, <em>Zoe</em> 4: 275.</p>
<p>Jones, M.E. (1895) <em>Astragalus douglasii</em> var. <em>glaberrimus</em> M. E.Jones. <em>Proceedings of the California Academy of Sciences</em> ser. 2 (5): 645.</p>
<p>Jones, M.E. (1895) <em>Astragalus piscinus</em> M. E. Jones. <em>Proceedings of the California Academy of Sciences </em>ser. <em>2</em>. 5: 645.</p>
<p>Jones, M.E. (1898) <em>Astragalus americanus. Contributions to Western Botany</em> 8: 8.</p>
<p>Jones, M.E. (1898) <em>A. insularis</em> var. <em>quentinus</em> M.E. Jones. <em>Contributions to Western Botany</em> 8: 6.</p>
<p>Jones, N.E. (1912) <em>Astragalus pueblae </em>M. E. Jones. <em>Contributions to Western Botany</em> 14: 35.&nbsp;</p>
<p>Jones, M.E. (1923) <em>Astragalus</em>. <em>Revision of North American</em> <em>Astragalus</em>. pp. 1–288. (distributed Feb.15) + Index to Plates and Plates 1–78 (distributed June 20).</p>
<p>Kazempour, O.S., Maassoumi, A.A. &amp; Murakami, N. (2003) Molecular systematics of the genus <em>Astragalus</em> L. (Fabaceae): phylogenetic analyses of nuclear ribosomal DNA internal transcribed spacers and chloroplast gene ndhF sequences. <em>Plant Systematics and Evolution</em> 242: 1–32.&nbsp;</p>
<p>Kazempour, O.S., Maassoumi, A.A. &amp; Murakami, N. (2005). Molecular systematics of the Old world <em>Astragalus</em> (Fabaceae) as inferred from nrDNA ITS sequence data. <em>Brittonia</em> 57: 367–381.&nbsp;[0367:MSOTOW]2.0.CO;2</p>
<p>Kellog, M.D. (1884) New species of Cedros Island Plants. <em>Bulletin of the Southern California Academy of Sciences</em> 1 (1): 6.</p>
<p>Lavin, M. &amp; Marriott, H. (1997) <em>Astragalus molybdenus</em> s.l. (Leguminosae): Higher taxonomic relationships and identity of constituent species. <em>Systematic Botany</em> 22 (2): 199–217.&nbsp;</p>
<p>Lewis, G.P. &amp; Schrire, B.D. (2003) <em>Leguminosae or Fabaceae?</em> <em>In</em>: Klitgaard, B. &amp; Bruneau, A. (Eds.) <em>Advances in legume systematics, part 10, Higher level systematics</em>. Richmond, U.K. Royal Botanic Gardens, Kew, pp. 1–3.</p>
<p>Lewis, G., Schrire, B., Mackinder, B. &amp; Lock, M. (2005) <em>Legumes of the world</em>. Royal Botanic Gardens, Kew, 577 pp.</p>
<p>Li, Q., Hu, J.H., Bo, G., Li, H.D., Song, S. &amp; Yang, L.X. (2017) Advances on Immunoregulation Effect of <em>Astragalus</em> polysaccharides<em>. Chinese Journal of Experimental Traditional Medical Formulae</em> 2: 199–206.</p>
<p>Linnaeus, C. (1753) <em>Species plantarum</em>. Vol. 2. Impensis Laurentii Salvii, Holmiae, 639 pp.</p>
<p>Linnaeus, C. (1767) <em>Astrgalaus sinicus. </em>Mantissa Plantarum.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</p>
<p>Liston, A. &amp; Wheeler, J.A. (1994) The phylogenetic position of the genus <em>Astragalus</em> (Fabaceae): evidence from the chloro–plast genes rpoC1 and rpoC2. <em>Biochemical Systematics and Ecology</em> 22: 377–388.&nbsp;</p>
<p>Liu, Z.G., Xiong, Z.M. &amp; Yu, X.Y. (2003) Effect of <em>Astragalus</em> injection on immune function in patients with congestive heart failure. <em>Chinese Journal of Integrative Medicine</em> 23: 351–353.</p>
<p>Lnag-rang, X. &amp; Podlech, D. (2010) <em>Astragalus</em> Linnaeus. <em>In</em>: Wu, Z.Y., Raven, P.H. &amp; Hong, D.Y. (Eds.) <em>Flora of China</em> 10. Science Press, Beijing and Missouri Botanical Garden Press, St. Louis, U.S.A., pp. 328–453.</p>
<p>Lock, J.M. &amp; Simpson, K. (1991) <em>Legumes of West Asia</em>: A Check–list. Royal Botanic Gardens, Kew.</p>
<p>Lock, M. &amp; Schrire, B. (2005) Tribe Galegeae. <em>In</em>: Lewis, G., Schrire, B., Mackinder, B. &amp; Lock, M. (Eds.) <em>Legumes of the world</em>. Royal Botanic Gardens, Kew, pp. 475–487.</p>
<p>Maassoumi, A.A. (1998) <em>Astragalus in the Old World</em>, Check List. Research Institute of Forests and Rangeland. Tehran, 617 pp.</p>
<p>Marin, R.E., Micheloud, J.F., Vignale, N.D., Gimeno, E.J., O’Toole, D., Gardner, D.R., Woods, L. &amp; Uzal, F.A. (2020) Intoxication by <em>Astragalus garbancillo</em> var. <em>garbancillo</em> in llamas. <em>Journal of Veterinary Diagnostic Investigation:</em> 1–4.&nbsp;</p>
<p>Marin, R.E., Gardner, D.R., Armien, A.G., Fortunato, R.H. &amp; Uzal, F.E. (2022) Intoxication of llamas by <em>Astragalus punae</em> in Argentina. <em>Journal of Veterinary Diagnostic Investigation:</em> 1–5.</p>
<p>McVaugh, R. (1987) <em>Flora Novo–Galiciana</em> Vol. 5. Leguminosae. The University of Michigan Press. Ann Arbor. Michigan, 786 pp.</p>
<p>Melgoza, A., Royo, M., Morales, C.R. &amp; Sierra, J.S. (2003) Germinación de semillas de hierba loca (<em>Astragalus mollissimus</em> Torr) con diferentes niveles de humedad y temperatura. <em>Tec Pecu Mex</em> 41(1):85–89</p>
<p>Moench, C. (1794) <em>Astragalus membranaceus</em>, Methodus (Moench) 168.</p>
<p>Panter, K.E., Welch, K.D., Gardner, D.R., Lee, S.T., Green, B.T., Pfister, J.A., Cook, D., Davis, T.Z. &amp; Stegelmeier, B.L. (2012) <em>Poisonous Plants of the United States</em>. <em>In</em>: Gupta, R.C. (Ed.) <em>Veterninary toxicology. Basic and clinical principles</em>. Cap. 61. Academic Press, pp. 837–889.</p>
<p>Podlech, D. (1983) Zur taxonomie und nomenclatur de tragacanthoiden Astragali. <em>Mitt. Bot. Staatss. Munchen </em>19: 1–23.</p>
<p>Pursh, F.T. (1813) <em>Astragalus racemosus. Flora Americae Septentrionalis</em> 2: 740.</p>
<p>Rebman, J., Gibson, J. &amp; Rich, K. (2016) Annotated checklist of the vascular plants of Baja California, Mexico. Proc. <em>San Diego Society of Natural History</em> 45: 1–352.</p>
<p>Rydberg, P.A. (1929) Genera of North American Fabaceae VI. Astragalus and related genera. <em>American Journal of Botany</em> 16 (4): 197–206.&nbsp;</p>
<p>Rzedowski, J. &amp; Rzedowski, G.C. (2015) Seis novedades de Leguminosae–Papilionoideae de México. <em>Acta Botanica Mexicana </em>110: 1–19.&nbsp;</p>
<p>Rzedowski, G.C. de &amp; J. Rzedowski y colaboradores (2010) <em>Flora fanerogámica del Valle de México</em>. Instituto de Ecología, A. C., edición digital.</p>
<p>Sanderson, M.J. (1991) Phylogenetic relationships within North American <em>Astragalus</em> L. (Fabaceae). <em>Systematic Botany</em> 16: 414–430.&nbsp;</p>
<p>Sanderson, M.J. &amp; Liston, A. (1995) Molecular phylogenetic systematics of Galegeae, with special reference to <em>Astragalus</em>. <em>In</em>: Crisp, M.D. &amp; Doyle, J.J. (Eds.) <em>Advances in legume Systematics–phylogeny</em> 7. Royal Botanic Garden, Kew, India, pp. 331–350.</p>
<p>Sanderson &amp; &amp; Wojciechowski, M.F. (1996) Diversification rates in a temperate legume clade: are there so many species of <em>Astragalus</em> (Fabaceae)? <em>American Journal of Botany </em>83: 1488–1502.</p>
<p>Semarnat Secretaría de Medio Ambiente y Recursos Naturales (2010)<em> Norma Oficial Mexicana NOM–059–SEMARNAT–2010</em>. Diario Oficial de la Federación (DOF), jueves 30 de diciembre de 2010.</p>
<p>Shahrajabian, M., Sun, W. &amp; Cheng, Q. (2019) A review of <em>Astragalus</em> species as foodstuffs, dietary supplements, a traditional Chinese medicine and a part of modern pharmaceutical Science. <em>Applied Ecology and Environmental Research</em> 17 (6): 13371–13382.&nbsp;</p>
<p>Shreve, F. &amp; Wiggins, I.L. (1964) <em>Vegetation and flora of the Sonoran Desert</em>. Stanford University Press, Stanford.</p>
<p>Sousa, S.M. &amp; Delgado, A. (1998) <em>Leguminosas mexicanas: fitogeografía, endemismo y orígenes.</em> <em>In</em>: Ramamoorthy, T.P., Bye, R., Lot, A. &amp; Fa, J. (Eds.) <em>Diversidad Biológica de México</em>. Instituto de Biología, Universidad Nacional Autónoma de México. México, D.F. pp. 449–500.</p>
<p>Spegazzini, C.L. (1902) <em>Astragalus nuttallianus</em> Speg., <em>Anales Mus. Nac. Buenos Aires</em> 7: 265.</p>
<p>Spellenberg, R., Lebgue, T. &amp; Corral–Díaz, R. (1996) <em>A specimen–based, annotated checklist of the vascular plants of Parque Nacional ‘‘Cascada de Basaseachi’’ and adjacent areas, Chihuahua, Mexico</em>. Listados Florísticos de México, XIII. Instituto de Biología, Univ. Autónoma de México, Mexico.</p>
<p>Spellenberg, R., Van Devender, R.T. &amp; Jenkins, P.D. (2014) <em>Astragalus martinii</em> (Fabaceae), a new species from eastern Sonora and western Chihuahua, Mexico. <em>Phytoneuron</em> 66: 1–8.</p>
<p>Spellenberg, R. &amp; Anderson, E.W. (2019) <em>Astragalus pilosior</em> (Fabaceae), a new species from the Sierra Madre Occidental in Chihuahua, Mexico. <em>Journal of the Botanical Research Institute of Texas</em> 13 (1): 131–140.</p>
<p>Taubert, P. (1894) <em>Leguminosae</em>. <em>In</em>: Engler, A. &amp; Prantl, K. (Eds.) <em>Die Naturlichen Pflanzenfamilien</em>, vol. III. Verlag von W Engelmann, Leipzig, pp. 70–385.</p>
<p>Thiers, B. (2021) [continuously updated] Index Herbariorum: A global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium. Available from: (accessed 21 June 2021)</p>
<p>Torrey, J. &amp; Gray, A. (1838) Tribe Astragaleae. <em>Flora of North America</em> 1: 328–353.</p>
<p>Villarreal, J.A. (2001) <em>Listados florísticos de México</em> XXIII. Flora de Coahuila. Universidad Nacional Autónoma de México. Instituto de Biología. México, 136 pp.</p>
<p>Villarreal, J.A. &amp; Carranza, M.A. (1994) Two new species of <em>Astragalus</em> (Leguminosae) from northeastern Mexico. <em>Brittonia</em> 46 (4): 335–339.&nbsp;</p>
<p>Wang, J., Jia, J., Song, L., Gong, X., Xu, J., Yang, M. &amp; Li, M. (2019) Extraction, structure, and pharmacological activities of <em>Astragalus</em> polysaccharides. <em>Applied Sciences</em> 9. 122.&nbsp;</p>
<p>Watson, S. (1882) <em>Astragalus giganteus</em>. <em>Proceedings of the American Academy of Arts and Sciences</em> 17: 370.</p>
<p>Watson, S. (1888) <em>Astragalus scalaris</em> S. Watson. <em>Proceedings of the American Academy of Arts and Sciences</em> 23: 270.</p>
<p>Whistler, R.L. (1993) <em>Exudate gums, in industrial gums</em>. Academic Press, pp. 309–339.</p>
<p>Wiggins, I.L. (1980) <em>Flora of Baja California</em>. Stanford University Press. Stanford.</p>
<p>Williams, M.C. &amp; Barneby, R.C. (1977) The occurrence of nitro-toxins in North American <em>Astragalus</em> (Fabaceae). <em>Brittonia</em> 29 (3): 310–331.</p>
<p>Wojciechowski, M.F., Sanderson, M.J., Baldwin, B.G. &amp; Donoghue, M.J. (1993) Monophyly of aneuploid <em>Astragalus</em> (Fabaceae): evidence from nuclear ribosomal DNA internal transcribed spacer sequences. <em>American Journal of Botany</em> 80: 711–722.&nbsp;</p>
<p>Wojciechowski, M.F., Sanderson, M.J. &amp; Hu, J. (1999) Evidence on the Monophyly of <em>Astragalus</em> (Fabaceae) and its Major Subgroups Based on Nuclear Ribosomal DNA ITS and Chloroplast DNA trnL Intron Data. <em>Systematic Botany </em>24 (3): 409–437.&nbsp;</p>
<p>Zarre, S. &amp; Azani, N. (2013) Perspectives in taxonomy and phylogeny of the genus <em>Astragalus</em> (Fabaceae): a review. <em>Progress in Biological Science</em> 3: 1–6.</p>