Northern Prairie Wildlife Research Center

Checklist of Amphibian Species and Identification Guide

An Online Guide for the Identification of Amphibians in North America north of Mexico


Identification Definitions

The following diagram displays the most commonly used terms when referring to the orientation of an organism.

Drawing by Jundt: Diagram of frog.

Anterior
Refers to the front or the head on the body of the organism.
Costal Grooves
The vertical folds on the sides of many salamanders (see fig.).
Dorsal
Refers to the "back" of the animal.
Dorsolateral
Refers to something between the back and the side of the organism.
Dorsolateral Folds
Lines of raised glandular skin in an area between the back and the sides.
Dorsum
The back of the animal.
Interorbital
Between the eyes.
Lateral
Refers to the sides of the organism.
Middorsal
Refers to the center of the back.
Parotid Gland
Large wart like galnd located behind the eye in some toads and salamanders.
Posterior
Refers to the caudal or rear of the body of the animal.
Postorbital
Behind the eyes.
Venter
The belly of the organism.
Ventral
Refers to the "belly" or underside of the animal.

Diagram of morphological features of toads (shown: interorbital ridge, postorbital ridge, and parotid gland)

Cranial Crests or Ridges. Raised ridges or crests on the head located behind and/or between the eyes in some toads.

Drawing by Jundt: Diagram showing Costal Grooves on salamander.

Costal Grooves in Salamanders. The number of folds is often constant or within a constant range for a given species. Counting them can help with species identification.


Return to Contents
Anura: Frogs and Toads - by Family / by Species
Caudata: Salamanders - by Family / by Species
NPWRC Home | Site Map | About Us | Staff | Search | Contact | Web Help | Copyright

Accessibility FOIA Privacy Policies and Notices

Take Pride in America home page. FirstGov button U.S. Department of the Interior | U.S. Geological Survey
URL: http://www.npwrc.usgs.gov/resource/herps/amphibid/define.htm
Page Contact Information: npwrc@usgs.gov
Page Last Modified: August 3, 2006