Nashville Zoo First to Hatch Obscure Lizard

Nashville Zoo is proud to announce the hatching of two crocodile tegus. The event marks the first hatching of this species in any organization accredited by the Association of Zoos and Aquariums (AZA). The new arrivals, both believed to be female, were born on May 7 and 14 and are currently being raised behind the scenes in the Zoo’s Herpetology Department.

Little is known about the crocodile tegu (Crocodilurus amazonicus). This semi-aquatic species is native to the wetlands and forests of South America in countries including Argentina, Paraguay, and Brazil. Crocodile tegus grow to about four feet in length and have long, flat, paddle-like tails making them excellent swimmers. Despite the name, the crocodile tegu is not related to crocodiles.

Nashville Zoo is the only AZA organization caring for crocodile tegus. In 2018, the Zoo acquired three juveniles (all female) and raised them in an off-exhibit area. The Zoo received a juvenile male in 2023 who was recently introduced to the females. Shortly after, one of the females laid a clutch of 10 eggs. Two of those eggs were viable resulting in the hatching.

“When I caught a first glimpse of that little hatchling, I was so excited my hands were shaking,” exclaimed Katie Gregory, Nashville Zoo Herpetology Keeper responsible for the care and breeding of this species. “We are thrilled to learn more about this largely unstudied species and share our discoveries with other AZA organizations and the rest of the world.”

Nashville Zoo has a history of being first in husbandry programs. In addition to being the first AZA organization to hatch crocodile tegus, the Zoo is proud to claim the following achievements:

• 1992 – First successful artificial insemination in a clouded leopard
• 1994 – First known breeding of the roughneck monitor lizard
• 1996 – First breeding of the Bengal monitor lizard at an AZA Institution
• 2001 – Frist breeding of the Cuban giant false chameleon at an AZA Institution
• 2002 – Frist known breeding of Haitian giant anole
• 2007 – First breeding of Central American galliwasps
• 2008 – First successful artificial incubation of a rhinoceros hornbill chick in the U.S.
• 2011 – First known breeding of a giant rainbow stripe galliwasp
• 2012 – First known breeding of an Eastern hellbender
• 2012 – First breeding of an externally fertilizing salamander species using in-vitro fertilization
• 2014 – First known breeding of a bumble bee toad
• 2015 – First production of an externally fertilizing salamander using artificial insemination and cryopreservation
• 2017 – First birth of a clouded leopard through artificial insemination and cryopreservation
• 2021 – First known breeding of a streamside salamander
• 2022 – First breeding of a Malpeo giant galliwasp