Green arboreal alligator lizard, Terrestrial arboreal alligator lizard
The Mexican alligator lizard (Abronia graminea) is an endangered species of lizard native to Mexico. It was originally described under the genus Gerrhonotus as Gerrhonotus gramineus by Edward D. Cope in 1864. Mexican alligator lizards especially favor living near bromeliads because the leaves of this plant collect water that is so essential for these lizards.
The Mexican alligator lizard has a dorsoventrally depressed body with a flattened, triangular head and weak lateral fold. It has a prehensile tail, that can be regrown if lost, and long, strong limbs and digits ideal for its arboreal habitat. The preauricular scales of this lizard are granular, and the dorsal scales are slightly keeled. The plates of the head are often thickened and roughed, giving the head a triangular appearance. The adult colour pattern varies significantly from the juvenile colouration. Adult males are typically bright emerald green while females exhibit colour variations that include bright to dull orange on the dorsal side. Other colour elements present in adults include bright yellow orbital skin, blue highlights on the supralabial scales, and yellow snout, lower jaw, and throat. Dorsal scales contain variable amounts of dark pigmentation on the basal half of the scales. Females of this species occasionally retain dark crossbands characteristic of juvenile colour patterns. Juveniles typically have a light tan ground colour with 9 irregular black crossbands on the body and 19 on the tail, and a dirty yellow ventrum.
This species is widely distributed in the highlands of Mexico along the Sierra Madre de Oaxaca mountain range. This range includes the states of Puebla, Veracruz, and Oaxaca. Mexican alligator lizards inhabit mesic, montane forest environments. They are usually found in cloud forests or pine-oak forests within humid temperate climates where the temperature can change dramatically between day and night. These lizards can be found among epiphytic vegetation, particularly bromeliads, but also lichens and orchids.
Mexican alligator lizards are solitary and arboreal. They live in trees and can be found at heights of 40 m (131 ft) in forest canopies. They are active during the day spending most of their time preying on insects.
Mexican alligator lizards are carnivores (insectivores) and feed on a wide variety of insects and other arthropods.
Mexican alligator lizards are considered to be viviparous (giving birth to live offspring). Mating typically occurs in the summer/fall, and parturition occurs in the spring. The gestation period lasts approximately 6-8 months and females can give birth to 1-12 young. Females of this species can become reproductively mature and start to breed in their 3rd year of life.
The main threats to this species include population fragmentation and destruction of habitat. Forest fires, deforestation, and change in land use for agricultural purposes have degraded this habitat and reduced the distribution of the Mexican alligator lizard dramatically. Illegal international trade for the purpose of maintaining it as a pet has also significantly contributed to the status of this species.
The IUCN Red List and other sources don’t provide the number of the Mexican alligator lizard total population size. Currently, this species is classified as Endangered (EN) on the IUCN Red List, and its numbers today are decreasing.
