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Amphibia    Anura    Scaphiopodidae  

Western Spadefoot
Spea hammondii (Baird, 1859 “1857”)
SPEE-ah — HAM-mond-ee-eye

SSAR 9th Edition Comments:
 There is considerable inconsistency in the older literature regarding this taxon and both S. multiplicata and S. intermontana. Recent genetic evidence suggests two allopatric clades (Northern and Southern) may warrant recognition of an undescribed species (Neal et al., 2018, Conservation Genetics 19: 937–946). (Mendelson, Joseph R., III, Darrel R. Frost, Emily Moriarty Lemmon, and Maureen A. Donnelly. 2025. Anura – Frogs. Pages 1-9 in Kirsten E. Nicholson (Editor), Scientific and Standard English Names of Amphibians and Reptiles of North America North of Mexico, with Comments Regarding Confidence in Our Understanding, 9th Edition. Society for the Study of Amphibians and Reptiles, Lawrence, Kansas. 87 pp.)

Range maps are based on curated specimens and provided gratis by CNAH.
(Created by Travis W. Taggart; Version: 2024.02.01.09.25.27)
Download GeoJSON polygon range file: - 0.41 MB

Province/State Distribution:
United States: California

Taxonomic Etymology:
Named for an early American explorer-naturalist.
Spea — From Greek σπαθη (spathē) = “blade” or “spade”. Spea is a Latinized form referencing the keratinous spade-like projection on the hind feet, which these frogs use for burrowing.
hammondii — Possibly a patronym honoring Dr. William A. Hammond (1828–1900), a U.S. Army surgeon and collector who obtained natural history specimens during western expeditions, including in California. Alternatively, the species may have been named for John F. Hammond (1820-1886), also a U.S. Army surgeon stationed in the southwest.

First instance(s) of published English names:
Hammond's Spade-foot (Scaphiopus hammondii: Cooper, James G. 1869. The fauna of California and its geographical distribution. Proceedings of the California Academy of Sciences 4():61-81); Hammond's Spea (Spea hammondi: Yarrow, Henry C. 1882. Check list of North American Reptilia and Batrachia with catalogue of specimens in U. S. National Museum. Bulletin of the United States National Museum (24):1-249); Western Spadefoot (Scaphiopus hammondii: Strecker, John K., Jr. 1922. An annotated catalogue of the amphibians and reptiles of Bexar County, Texas. Bulletin Scientific Society of San Antonio (4):1-31); Western Spadefoot Toad (Scaphiopus hammondii: Wright, Anna Allen, and Alex Hazen Wright. 1933. Handbook of frogs and toads. The frogs and toads of the United States and Canada Comstock Publishing Associates, Ithaca, NY. xi+231pp.); Hammond's Spadefoot (Scaphiopus hammondii: Wright, Anna Allen, and Alex Hazen Wright. 1933. Handbook of frogs and toads. The frogs and toads of the United States and Canada Comstock Publishing Associates, Ithaca, NY. xi+231pp.); Western Spadefoot (Scaphiopus hammondi hammondi: Schmidt, Karl P. 1953. A Check List of North American Amphibians and Reptiles. 6th Edition. University of Chicago Press, Chicago, Illinois. 280pp.);

Taxon Links:

  
Catalog of American Amphibians and Reptiles
  
Amphibian Species of the World
  
NatureServe
  
iNaturalist
  
GenBank
  
USGS - Nonindigenous Aquatic Species Database

Selected References:
1859 "1857" Baird, Spencer F. Report upon the reptiles of the route, in Explorations and Surveys, R.R. Route from the Mississippi River to the Pacific Ocean, 1853-56. Pages Pp.37-45 in Vol. 10, Williamson's Route. Zoological Report, Part 6, Number 4. US Government, Washington, D. C.. pp.
1890 Stejneger, Leonhard H. Part V. - Annotated list of reptiles and batrachians collected by Dr. C. Hart Merriam and Vernon Bailey on the San Francisco Mountain Plateau and Desert of the Little Colorado, Arizona, with descriptions of new species. North American Fauna 3(3):103-118
1939 Tanner, Vasco M. A study of the genus Scaphiopus. Western North American Naturalist 1(1):3-26
1950 Firschein, I. Lester. A new record of Spea bombifrons from northern Mexico and remarks on the status of the hammondii group of spadefoot anurans. Herpetologica 6:75-77
1954 Lowe, Charles H., Jr. Isolating mechanisms in sympatric populations of southwestern anurans. Texas Journal of Science 6(3):265-270
1955 Blair, W. Frank. Differentiation of mating call in spadefoots, genus Scaphiopus. Texas Journal of Science 7(2):183-188
1956 Chrapliwy, Pete S. Taxonomy and distribution of the spadefoot toads of North America (Salientia: Pelobatidae). Thesis. University of Kansas, Lawrence. 131pp.
1957 Wasserman, Aaron O. Factors affecting interbreeding in sympatric species of spadefoots (genus Scaphiopus). Evolution 11(3):320-338
1967 Brown, Herbert A. Embryonic temperature adaptations and genetic compatibility in two allopatric populations of the spadefoot toads (genus Scaphiopus). Los Angeles County Museum Contributions in Science (286):1-15
1967 Brown, Herbert A. Embryonic temperature adaptations and genetic compatibility in two allopatric populations of the spadefoot toad, Scaphiopus hammondi. Evolution 21(4):742-761
1976 Brown, Herbert A. The status of California and Arizona populations of the western spadefoot toads (genus Scaphiopus). Natural History Museum of Los Angeles County, Contributions in Science (286):1-14
1980 Sattler, P. W. Genetic relationship among selected species of North American Scaphiopus. Copeia 1980(4):605-610
1989 Tanner, Wilmer W. Status of Spea stagnalis Cope (1875), Spea intermontanus Cope (1889), and a systematic review of Spea hammondii Baird (1839) (Amphibia: Anura). Great Basin Naturalist 49:503-510
1991 Wiens, John J. and Tom A. Titus. A phylogenetic analysis of Spea (Anura: Pelobatidae). Herpetologica 47(1):21-28
2000 Maglia, Anne M. Phylogenetic Relationships of Pelobatoid Frogs (Anura: Pelobatoidea). Dissertation. University of Kansas, Lawrence, Kansas. pp.
2002 Buchholz, Daniel R. and Tyrone B. Hayes. Evolutionary patterns of diversity in spadefoot toad metamorphosis (Anura: Pelobatidae). Copeia 2002(1):180-189
2018 Neal, Kevin M., B. B. Johnson, and H. Bradley Shaffer. Genetic structure and environmental niche modeling confirm two evolutionary and conservation units within the western spadefoot (Spea hammondii). Conservation Genetics 19:937-946
2019 Neal, Kevin M. An integrative population and landscape genomic approach to conservation of a threatened California amphibian at multiple spatial scales. Dissertation. University of California, Los Angeles, Los Angeles, California. 170pp.

THE CENTER FOR NORTH AMERICAN HERPETOLOGY — Accessed: Friday 05 December 2025 15:56 CT