Under Construction

Rhinophrynus dorsalis

Mexican Burrowing Toad

David Cannatella
Click on an image to view larger version & data in a new window
Click on an image to view larger version & data in a new window
Rhinophrynus dorsalis
Containing group: Rhinophrynidae


Rhinophrynus dorsalis is the only living member of the family Rhinophrynidae. It is one of the strangest of frogs. This animal is highly fossorial (adapted for burrowing) and apparently only comes to the surface to breed, and then only during very heavy rains. The head is small and cone-shaped, and not surprisingly, the skull resembles that of a mole (Spalax). The skin is quite thick, and an early naturalist described the frog (in French) as a bag of bones. It ranges through the southern Rio Grande Valley of Texas to Costa Rica. This frog is 5-7 cm long. There is usually a broad red or orange stripe down the middle of the back. There is a spade, used for digging, on the inner edge of the foot; the first toe is also modified to extend the functional edge of the spade.

Rhinophrynus dorsalis is specialized for eating termites, and the tongue seems to be particularly modified for this activity. Instead of being flipped out over itself, as in most frogs, the tongue is projected straight out of the mouth (Trueb, 1983).

Many small eggs are laid in water, and the tadpoles aggregate and form large schools. They are specialized for filter-feeding on small particles suspended in the water, rather than grazing on algae or eating detritus from the bottom of the pond. Correlated with this behavior, the larvae lack beaks and denticles; they also have paired spiracles like most pipid tadpoles. This type of tadpole (Orton Type 1) is evidence of a close phylogenetic relationship between Rhinophrynidae and Pipidae.

Geographic Distribution

Click on an image to view larger version & data in a new window
Click on an image to view larger version & data in a new window

The distribution of Rhinophrynus dorsalis is indicated in red. The species is found in coastal lowlands of southern North America and Central America.

Other Names for Rhinophrynus dorsalis


Trueb, L. 1983. Feeding specializations of the Mexican burrowing toad, Rhinophynus dorsalis (Anura: Rhinophrynidae). J. Zool., Lond. 199:189-208.

Title Illustrations
Click on an image to view larger version & data in a new window
Click on an image to view larger version & data in a new window
Rhinophrynus dorsalis
Scientific Name Rhinophrynus dorsalis
Image Use creative commons This media file is licensed under the Creative Commons Attribution-ShareAlike License - Version 3.0.
Copyright © 1995 David Cannatella
About This Page

David Cannatella
University of Texas, Austin, Texas, USA

Correspondence regarding this page should be directed to David Cannatella at

Page: Tree of Life Rhinophrynus dorsalis. Mexican Burrowing Toad. Authored by David Cannatella. The TEXT of this page is licensed under the Creative Commons Attribution License - Version 3.0. Note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. Click on an image or a media link to access the media data window, which provides the relevant licensing information. For the general terms and conditions of ToL material reuse and redistribution, please see the Tree of Life Copyright Policies.

Citing this page:

Cannatella, David. 2008. Rhinophrynus dorsalis. Mexican Burrowing Toad. Version 25 November 2008 (under construction). http://tolweb.org/Rhinophrynus_dorsalis/17528/2008.11.25 in The Tree of Life Web Project, http://tolweb.org/

edit this page
close box

This page is a Tree of Life Leaf Page.

Each ToL leaf page provides a synopsis of the characteristics of a group of organisms representing a leaf at the tip of the Tree of Life. The major distinction between a leaf and a branch of the Tree of Life is that a leaf cannot generally be further subdivided into subgroups representing distinct genetic lineages.

For a more detailed explanation of the different ToL page types, have a look at the Structure of the Tree of Life page.

close box

Rhinophrynus dorsalis

Page Content

articles & notes



Explore Other Groups

random page

  go to the Tree of Life home page