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9- Crocodilurus genus : 

Only one species in this genus :


Crocodilurus amazonicus — Crocodile Tegu

Crocodilurus amazonicus — Crocodile Tegu :

courtesy to :

Along Rio Orosa, Loreto, Peru—January 17, 2013

Mike Pingleton and I were drifting back towards the Madre Selva field station after a leisurely morning of kayaking when my brain registered an unusual shape on top of a hunk of log suspended in some vines along the edge of the Rio Orosa. I had already kayaked at least a hundred feet past this log, but I thought I should go back and investigate. Sure enough, as I got closer, I recognized the distinctive shape of a basking lizard. And not just any boring run-of-the-mill lizard either, but a particularly colorful one. I recognized it as a teiid, and knew that there was a large aquatic teiid in the area called the Crocodile Tegu, but this lizard wasn't all that large and I wasn't quite sure what Crocodile Tegus looked like. Mike was pretty sure it was in fact a Crocodile Tegu though, and indeed so it turned out to be. Turns out the young ones are very colorful; the big adults are much less so.



The tegu cooperated for an unreasonable length of time, as Mike and I took turns nudging our kayaks into the vegetation to get ever-closer photos of the lounging lizard. When we were satisfied with the picture-taking, Mike suggested that we might be able to catch it to bring back for others to admire. This seemed worth trying, so I nudged my kayak even a little bit closer and started leaning lizard-ward. But even this lazy lizard had limits, and that was enough to spook it into abandoning its perch and diving into the water below.


So we continued our kayak journey back to the field station, one of us on each side of the river to best notice any more interesting wildlife that we might chance upon. About five minutes later, I was thinking how it was sad that I hadn't managed to catch the tegu, and how I should have waited for Mike to try to block its exit path before making my move, when my eye happened to glance down at a little floating vegetation just to the left of the kayak. And what should be sticking up from that very floating vegetation but the head of another, even smaller, Crocodile Tegu. Before my brain had fully processed what it was seeing, my left hand had snatched that little guy out of the water. I called over to Mike, laughing: "I caught a different one!" Neither of us had any sort of bag, so Mike graciously sacrificed one of his socks to hold the little tegu until we got back to the field station.


I never ended up taking photos of the little guy I grabbed, but Matt Cage took some beautiful photos, and generously allowed me to use them here and anywhere else I choose. The last photo above is one of his -- thanks Matt!


Here is a complete list of the herps I saw in the wild on my 2013 MT Amazon Expeditions trip.

Along Rio Orosa, Loreto, Peru—January 14, 2014



This year I went kayaking with Matt Cage and Lorrie Smith. On the way out to the drop-off point, while we were still in the speedboat, a crew member and I both saw a big green lizard stretched out on a branch overhanging the river. He turned the boat back that way and I tried to focus my camera as we approached, but the camera chose to focus on the foreground branches in the one photo I managed to take before the lizard dove into the water.


On the way back, I spotted another one in a similar position. This one was much more cooperative, and Matt and I both got decent photos of it from our kayaks. Both of this year's Crocodile Tegus were much larger than both of last year's.


Here is a complete list of the herps I saw in the wild on my 2014 MT Amazon Expeditions trip.


Printed references:


  • Bartlett, R.D., and Bartlett, P. 2003. Reptiles and Amphibians of the Amazon: An Ecotourist's Guide

  • Dixon, J. R. and Soini, P. 1986. The Reptiles of the Upper Amazon Basin, Iquitos Region, Peru

  • Duellman, W.E. 2005. Cusco Amazónico: The Lives of Amphibians and Reptiles in an Amazonian Rainforest



Video : 

SLIDESHOW: Male Crocodilurus Amazonicus (Crocodile Tegu)

Crocodile Tegu - Crocodilurus amazonicus 


courtesy to :

Scientific classification :
Kingdom: Animalia
Class: Reptilia
Order: Squamata
Family: Teiidae
Genus: Crocodilurus
Species: C. amazonicus

C. amazonicus is a large, semi- aquatic teiid. The head is green with black mottled coloration. Throat coloration is typically yellow.The eye is large, with a round pupil. The rest of the body is a mottled grey/ green combo action, with large yellow spots located down the animals' abdomen. Young animals typically have red coloration on their forelimbs and tail; adults too have this coloration, but it is less pronounced.The tail is compressed and elongated, and the legs are short but powerfully built to aid with aquatic locomotion. Sexual dimorphism does not appear to be present within the species. Females average roughly 190mm(7.4in) in snout-vent length, and a tail length of ~407mm(15.7in). Males average a snout-vent length of 187mm(7.3in) and ~401mm(15.7in)tail length.{1} 


Geographic range & habitat:
This species is found in Colombia, Venezuela, French Guiana, Brazil, and Peru. The crocodile tegu can be found in close proximity to large bodies of water(I.e. rivers, lagoons, etc.). It can commonly be found basking on branches hanging over the water, and will jump in without hesitation if approached.

Dietary habits:
The crocodile tegu is an aquatic forager, and subsequently the prey taken is that of the aquatic variety. These lizards avoid competing for food resources with the sympatric Caiman lizard( D. Guinaensis) by having generalistic diet habits, feeding on Arthropods, crustaceans, fish, and anurans{2}while the caiman lizard is a specialized durophagous animal feeding almost entirely on molluscs.


Mating occurs annually, with a typical clutch size being four or five eggs. Clutch size in comparison with other south american Teiids is small - those of the Tupinambis genus lay as many as twenty eggs.


Adjoining account :
"Crocodilurus amazonicus is a medium-sized neotropical lizard widely distributed throughout the Amazon Basin and Orinoco River. It prefers semi-aquatic habitats, often being found near water. There are few published accounts of the ecology and natural history of this lizard. Vanzolini and Valencia (1965. Arq. Zool. São Paulo 13:7–46) described C. amazonicus dentition as insectivorous, whereas Presch (1974. Herpetologica 30[4]:344–349) suggested that C. amazonicus dentition is adapted for grasping and tearing large prey. Vertebrates have been recorded for the diet of C. amazonicus, including anurans, a snake, and fish (Costa et al. 2005. Herpetol. Rev. 36:174–175; Mesquita et al. 2006. J. Herpetol. 40:221–229). The identity of fish species consumed and the method of prey capture remain unknown. On 25 March 2014 we observed C. amazonicus preying on a fish, Pterophyllum scalare (Discus Flag) (Fig. 1A, B), on the Rio Solimões in municipality of Iranduba, Amazonas, Brazil"
From the herpetological review (2015)


{1} Mesquita, Daniel O., et al. "At the water's edge: ecology of semiaquatic teiids in Brazilian Amazon." Journal of Herpetology 40.2 (2006): 221-229.
{2} Martins, Marcio. "Life in the water: Ecology of the jacarerana lizard, Crocodilurus amazonicus." The Herpetological Journal 16.2 (2006): 171-176.

  crocodile tegu and caiman lizard.

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