Incilius alvarius (Girard, 1859)

Class: Amphibia > Order: Anura > Family: Bufonidae > Genus: Incilius > Species: Incilius alvarius

Bufo alvarius Girard In Baird, 1859, Rep. U.S-Mex. Bound. Surv., 2(Pt. 2-Rept.): 26. Syntypes: USNM 2571-72, according to Kellogg, 1932, Bull. U.S. Natl. Mus., 160: 38-39 (see discussion by Fouquette, 1968, Great Basin Nat., 28: 70-72); USNM 2572 considered "holotype" by Cope, 1889, Bull. U.S. Natl. Mus., 34: 267 (constituting a lectotype designation by implication), and subsequently designated lectotype formally by Fouquette, 1968, Great Basin Nat., 28: 71. Type locality: "Valley of the Gila and Colorado [Rivers]"; corrected to "Fort Yuma, Cal[ifornia].", USA by Cope, 1889, Bull. U.S. Natl. Mus., 34: 267; restricted to "Yuma", Yuma Co., Arizona by Smith and Taylor, 1950, Univ. Kansas Sci. Bull., 33: 355; restricted to "Colorado River bottomlands below Yuma, Arizona", USA, by Schmidt, 1953, Check List N. Am. Amph. Rept., Ed. 6: 61; corrected to "[old] Fort Yuma, Imperial County, California (on the north bank of the Colorado River, opposite its junction with the Gila River", USA, by Fouquette, 1968, Great Basin Nat., 28: 70-72.

Phrynoidis alvariusCope, 1862, Proc. Acad. Nat. Sci. Philadelphia, 14: 358.

Cranopsis alvariaFrost, Grant, Faivovich, Bain, Haas, Haddad, de Sá, Channing, Wilkinson, Donnellan, Raxworthy, Campbell, Blotto, Moler, Drewes, Nussbaum, Lynch, Green, and Wheeler, 2006, Bull. Am. Mus. Nat. Hist., 297: 364.

Ollotis alvariaFrost, Grant, and Mendelson, 2006, Copeia, 2006: 558, by implication.

Incilius alvariusFrost, Mendelson, and Pramuk, 2009, Copeia, 2009: 418, by implication.

Bufo (Incilius) alvarius — Fouquette and Dubois, 2014, Checklist N.A. Amph. Rept.: 314. See comment under Bufonidae regarding how this arrangement is part of a a system that requires widespread paraphyly. 

English Names

Colorado Toad (Cooper, 1873, Proc. California Acad. Sci., 4: 66). 

Girard's Toad (Yarrow, 1882, Bull. U.S. Natl. Mus., 24: 23).

Colorado River Toad (Storer, 1925, Univ. California Publ. Zool., 27: 43; Wright and Wright, 1933, Handb. Frogs Toads U.S. Canada: ix; Stebbins, 1951, Amph. W. North Am.: 229; Schmidt, 1953, Check List N. Am. Amph. Rept., Ed. 6: 61; Conant, Cagle, Goin, Lowe, Neill, Netting, Schmidt, Shaw, Stebbins, and Bogert, 1956, Copeia, 1956: 176; Stebbins, 1966, Field Guide W. North Am. Rept. Amph.: 59; Collins, Huheey, Knight, and Smith, 1978, Herpetol. Circ., 7: 10; Liner, 1994, Herpetol. Circ., 23: 16; Frank and Ramus, 1995, Compl. Guide Scient. Common Names Amph. Rept. World: 40; Collins, 1997, Herpetol. Circ., 25: 11; Crother, Boundy, Campbell, de Queiroz, Frost, Highton, Iverson, Meylan, Reeder, Seidel, Sites, Taggart, Tilley, and Wake, 2001 "2000", Herpetol. Circ., 29: 6).

Giant Toad (Slevin, 1928, Occas. Pap. California Acad. Sci., 16: 108).

Sonoran Desert Toad (Stebbins, 1985, Field Guide W. Rept. Amph., Ed. 2: 69; Stebbins, 2003, Field Guide W. Rept. Amph., Ed. 3: 207; Frost, McDiarmid, and Mendelson, 2008, in Crother (ed.), Herpetol. Circ., 37: 9; Liner and Casas-Andreu, 2008, Herpetol. Circ., 38: 18; Collins and Taggart, 2009, Standard Common Curr. Sci. Names N. Am. Amph. Turtles Rept. Crocodil., ed. 6: 6; Frost, McDiarmid, Mendelson, and Green, 2012, in Crother (ed.), Herpetol. Circ., 39: 16; Frost, Lemmon, McDiarmid, and Mendelson, 2017, in Crother (ed.), Herpetol. Circ., 43: 12).


Extreme southeastern California, southern Arizona, and extreme southwestern New Mexico (USA) and adjacent northwestern Chihuahua (Mexico) south through Sonora and to northwestern Sinaloa (Mexico) in arid tropical scrub and desert up to oak woodland and juniper-grassland, sea level to 1763 m elevation.


Reviewed by Fouquette, 1970, Cat. Am. Amph. Rept., 93: 1-4. In the monotypic Bufo alvarius group of Martin, 1972, in Blair (ed.), Evol. Genus Bufo: 40. Stebbins, 2003, Field Guide W. Rept. Amph., Ed. 3: 207-208, provided a brief account, figure, and map. Mendelson, Mulcahy, Williams, and Sites, 2011, Zootaxa, 3138: 1-34, suggested on the basis of morphology and molecular evidence that Incilius alvarius is the sister taxon of Incilius occidentalis + Incilius mccoyi and otherwise in an unnamed monophyletic group (the name Incilius alvarius group is availabe-DRF) including Incilius alvarius, Incilius occidentalis, Incilius mccoyi, and Incilius tacanensisLemos-Espinal, 2007, Anf. Rept. Chihuahua Mexico: 33-34, provided an account (as Bufo alvarius) for Chihuahua. Oliver-López, Woolrich-Piña, and Lemos-Espinal, 2009, Fam. Bufonidae Mex.: 55–57, provided an account (as Ollotis alvaria), although the range map is imprecise and substantially incorrect for the USA.  Dodd, 2013, Frogs U.S. and Canada, 1: 177–180, provided an account (as Ollotis alvaria) that summarized relevant literature. Fouquette, Painter, and Nanjappa, 2005, in Lannoo (ed.), Amph. Declines: 384–386, provided a brief but detailed account. Elliot, Gerhardt, and Davidson, 2009, Frogs and Toads of N. Am.: 168–169, provided an account, photos, and advertisement call. Altig and McDiarmid, 2015, Handb. Larval Amph. US and Canada: 186–187, provided an account of larval morphology and biology.      

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