Identification: Rhinella horribilis is a large, warty, brown or dark-mottled terrestrial toad (bufonid) that can weigh up to 1.5 kg (3.3 lbs) (Powell et al. 2016). External morphology is indistinguishable from R. marina, requiring radiographical examination of skull morphology or genetic testing to differentiate them (Acevedo et al. 2016; Bessa-Silva et al. 2020).
Like R. marina, these toads have a pair of large parotoid glands that produce bufotoxins, which act as neurotoxins, each extending from just behind the eye, far down the side of the body (Powell et al. 2016; Powell et al. 1998; Lever 2001). The pupils of the eye are horizontal and the irises golden, with distinct ridges running from above their eyes down the snout (Powell et al. 2016). The tadpoles are black dorsally, with a belly that is silvery white with black spots (Ashton and Ashton 1988; Lee 1996). Adult males can be identified by their more robust forelimbs for amplexus than adult females (Lee 2001). Tadpoles of R. marina are illustrated in Lee (1996), McKeown (1996), Lever (2001), Savage (2002), and Duellman (2005).
Unlike native Southern Toads (Anaxyrus terrestris) and American Toads (A. americanus) which have relatively small, oval paratoid glands, the paratoid glands of Cane Toads (Rhinella spp.) are large and triangular paratoid glands. Cane toads also have ridges or crests on top of the head between the eyes.
Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Rhinella horribilis are found here.
Table last updated 10/4/2022
† Populations may not be currently present.
References: (click for full references)
Abercrombie, H.E., M. Ferrera, P. Schultz, S. Watkins, E. Eversole, D.B. Estabrooks, and N.Ferrera. 2022. Geographic Distribution: Rhinella Horribilis
. Herpetological Review 53(1):74.
Acevedo, A.A., M. Lampo, and R. Cipriani. 2016. The cane or marine toad, Rhinella marina (Anura, Bufonidae): two genetically and morphologically distinct species. Zootaxa 4103(6):574-586.
Ashton, R.E., and P.S. Ashton. 1988. Handbook of Reptiles and Amphibians of Florida. Part Three: The Amphibians. Volume 3. Windward Publishing, Inc Miami, FL.
Bessa-Silva, A., M. Vallinoto, I. Sampaio, O. Flores-Villela, E. N. Smith, and F. Sequeira. 2020. The roles of vicariance and dispersal in the differentiation of two species of the Rhinella marina species complex. Molecular p 145(106723):1-12.
Duellman, W.E. 2005. Cusco Amazónico. The Lives of Amphibians and Reptiles in an Amazonian Rainforest. Comstock Publishing Associates, Cornell University Press.
King, F.W., and T. Krakauer. 1966. The exotic herpetofauna of southeast Florida. Quarterly Journal of the Florida Academy of Sciences 29(2):144-154.
Lee, J.C. 1996. The Amphibians and Reptiles of the Yucatan Peninsula. Cornell University Press.
Lee, J. C. 2001. Evolution of a secondary sexual dimorphism in the toad, Bufo marinus. Copeia 2001(4):928-935.
Lever, C. 2001. The Cane Toad. The History and Ecology of a Successful Colonist. Westbury Academic and Scientific Publishing, Otley, West Yorkshire, England.
McKeown, S. 1996. A Field Guide to Reptiles and Amphibians in the Hawaiian Islands. Diamond Head Publishing, Inc., Los Osos, California.
Powell, R.J.T. Collins, and E.D. Hooper, Jr. 1998. A Key to Amphibians & Reptiles of the Continental United States and Canada. University Press of Kansas, Lawrence.
Powell, R., R. Conant, and J.T. Collins. 2016. Peterson field guide to reptiles and amphibians of eastern and central North America. 4th edition. Houghton Mifflin Harcourt Publishing Company, New York, NY.
Savage, J.M. 2002. The Amphibians and Reptiles of Costa Rica. A Herpetofauna between Two Continents, between Two Seas. The University of Chicago Press, Chicago and London.
This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.