The non-native lizards breeding in Florida now outnumber the native species, and there are several large, invasive lizards that are of special concern. This fact sheet, best viewed as a pdf (https://edis.ifas.ufl.edu/UW352), is a quick reference guide to identification of the largest lizards you are likely to see in Florida, and the appropriate action to take in the event of an encounter. Report sightings and view maps of locations where each species has been encountered in Florida by visiting the EDDMapS Florida invasive species reporting portal online at http://www.IveGot1.org. Learn more about how to scan for, recognize, and report introduced reptiles by completing the Introduced Reptile Early Detection and Documentation training course. Visit http://ufwildlife.ifas.ufl.edu/reddy.shtml to learn more and get REDDy!
Native Species—Do Not Report
American Alligator (Alligator mississippiensis)
Status: native species found throughout Florida
Size: grows to 14 ft. long
Body: black; juveniles (up to 6 ft. long) with light-colored bands that fade with age
Other: enlarged, bony scales and webbed feet with claws
Note: Alligators are reptiles (i.e., Class Reptilia) but they are not lizards (Order Squamata)—they are crocodilians (Order Crocodilia).
Invasive Carnivorous Lizards—Report Immediately!
To learn more about how to recognize and report invasive carnivorous lizards, get REDDy—visit http://ufwildlife.ifas.ufl.edy/reddy.shtml
Nile Monitor (Varanus niloticus)
Status: breeding populations in southern Florida in Lee County and potentially also in Miami-Dade, Broward, and Palm Beach counties; other monitor lizard species are occasionally sighted, likely escaped or released pets
Size: grows to ~6 ft. long
Head: V-shaped marks on neck behind eyes
Body: grayish brown; rows of lighter spots across body, spots fuse into bands on tail
Giant Argentine Tegu a.k.a. Black-and-White Tegu (Salvator merianae)
Status: breeding populations in southern Miami-Dade and Hillsborough counties; other tegu species are occasionally sighted, likely escaped or released pets
Size: can grow to over 4 ft. long
Head: greenish when young
Body: grayish to reddish; marked with dark bands
Invasive Omnivorous Lizards—Document Sightings Online
Upload photos to document sightings by visiting http://www.IveGot1.org.
Black Spiny-Tailed Iguana (Ctenosaura similis)
Status: breeding populations in Sarasota, Lee, Charlotte, Collier, Broward, and Miami-Dade counties
Size: can grow to over 4 ft. long
Body: grayish; marked with dark bands; spikes down the back (more prominent in males) and rings of spikes around the tail
Green Iguana (Iguana iguana)
Status: breeding populations in Lee, Collier, Monroe, Miami-Dade, Broward, and Palm Beach counties; sightings and potential for breeding as far north as Indian River County on the East Coast
Size: grows up to 6 ft. long
Head: may be reddish; large, round scale on each cheek; large throat fan (dewlap)
Body: greenish to grayish (juvenile bright green); tail with dark bands; spikes down the back
This project was made possible in part by a grant from the South Florida National Parks Trust and the Ferris Greeney Family Foundation, and by the USDA-RREA. This document was originally created as additional reference material for the Introduced Reptile Early Detection and Documentation training program, also known as REDDy. For more information, visit http://ufwildlife.ifas.ufl.edu/reddy.shtml.