Astragalus endopterus (Fabaceae), a species purported as extinct, found in northern Arizona, U.S.A.


  • Glenn Rink Northern Arizona University



Astragalus endopterus (Barneby) Barneby, listed as an extinct species in a recent Conservation Biology paper (Knapp et al. 2021) was found in abundance after three hours of targeted searching. Continued searches revealed thousands of plants. Our work has doubled the known range of the species. Astragalus endopterus seems to mostly occur on sheetwash deposits composed of particles derived mostly from windblown sands along with a component of clay probably derived from the Chinle Formation. We have no indications that the species may have been in decline or was ever on the verge of extinction.


ARIZONA GAME AND FISH DEPARTMENT. 2020. Astragalus endopterus. Unpublished abstract compiled and edited by the Arizona Natural Her-itage Data Management System, Arizona Game and Fish Department, Phoenix, Arizona, U.S.A. 4 pp.

ARIZONA RARE PLANT COMMITTEE. No date. Arizona rare plant field guide, a collaboration of agencies and organizations. Available at

BARNEBY, R. 1949. Pugillus Astragalorum X: New species, varieties and combinations. Amer. Midl. Naturalist 41(2):498.

BARNEBY, R. 1964. Atlas of North American Astragalus. Mem. New York Bot. Gard 13:879.

DAU, J.H., U.A. DONALD-AMAECHI, & O. CHUKWU. 2018. Seed banks as conservation tool for endangered wild plant species in ecozones of Nigeria. J. Res. Forest. Wildlife & Environ. 10(3):69–78.

FABER-LANGENDOEN, D. (& 10 others). 2012. NatureServe conservation status assessments: methodology for assigning ranks. NatureServe, Arlington, Virginia, U.S.A.

KNAPP, W.M. (& 14 others). 2021. Vascular plant extinction in the continental United States and Canada. Conservation Biol. 35(1):360–368.

LAURENZI, A. & J. SPENCE. 2013. Conservation priority setting for Arizona G1 and G2 plant species: a regional assessment. The Plant Press, Arizona Native Plant Society, Tucson, Arizona, U.S.A.

RINK, G. & T. EMBREY. 2023. Survey for Astragalus endopterus (Barneby) Barneby (Fabaceae) Coconino and Navajo counties, Arizona June and July, 2023. Final Section 6 Report, Segment 28: Reference #2022-2024-09, unpublished report for the US Fish and Wildlife Service, U.S.A.


STEWART, J.H., F.J. POOLE, & R.F. WILSON. Stratigraphy and origin of the Chinle Formation and related Upper Triassic strata in the Colorado Plateau Region. Geological Survey Professional Paper 690, prepared on behalf of the U.S. Atomic Energy Commission. U.S. Government Printing Office, Washington, DC, U.S.A.

WALTERS, C. & V.C. PENCE. 2021. The unique role of seed banking and cryobiotechnologies in plant conservation. Plants, People, Planet 3:83–91.

WELSH, S.L. 2023. Astragalus. In: Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 25+ vols. New York and Oxford. 11(2):584–900.




How to Cite

Rink, G. (2024). Astragalus endopterus (Fabaceae), a species purported as extinct, found in northern Arizona, U.S.A. Journal of the Botanical Research Institute of Texas, 18(1), 205–210.