Crested Anole

Appearance

Compared to many other anoles, it is a stocky, muscular and aggressive, although it is a small to moderately-sized species. Measurements in 2015 found the animals to have a snout-vent length which can reach to 75 mm in males, and up to 73 mm in females, although most females are much smaller.

It is sexually dimorphic, with the males being prettier than the females. The juvenile lizards are also coloured differently than adults. The males of this species are easily recognizable by their permanently erect caudal crests -which is a high sail- or fin-like structure running down the top of their tails, which is supported anatomically by bony extensions of the vertebrae. The crest is very short along the animals back, and gets higher again on the nape of the neck. The tail is compressed in cross-section.

The colour is variable; the head and body are bronze to greenish grey, with faint and irregular brownish spots, and the belly is greenish-yellow and the throat is whitish. The iris is dark brown. The male dewlaps is coloured mustard or greenish yellow, with a burnt-orange, reddish-orange to reddish-coloured band along the margin. Females have a well developed but smaller dewlap and a low caudal crest. The juveniles are transversely banded in brown, with some purplish-brown dots on the throat and the crotch , and often have a light mid-dorsal stripe, which some females retain into adulthood.

It can change its colour significantly from a very light grey to reddish-brown and dark black, and can shift colour in reaction to its behavioural state. They are thus often referred to as 'chameleons' in many places because of their ability to change colour, but they are not related to true chameleons.

Naming

As of 2020 there are two subspecies recognised:
⤷  ''Anolis cristatellus cristatellus'' – Puerto Rico, including some off-shore islands; introduced elsewhere.
⤷  ''Anolis cristatellus wileyae'' Grant, 1931 – Culebra and Vieques islands east of Puerto Rico and the U.S. and British Virgin Islands.

Status

This is an extremely common species in Puerto Rico, and it is believed that it has likely become more common over the last few centuries as humans have converted much more of the island to the type of habitat that this species prefers.

The IUCN has not evaluated this species' conservation status.

It has been recorded as present in the following protected areas:
⤷ Reserva Natural Caja de Muertos, Ponce, Puerto Rico, USA.
⤷ Guánica State Forest, Puerto Rico, USA.
⤷ Los Tres Picachos State Forest, Puerto Rico, USA.
⤷ Luquillo Experimental Forest within El Yunque National Forest, Puerto Rico, USA.
⤷ Reserva Forestal de Maricao, Puerto Rico, USA.
⤷ Virgin Islands National Park, Saint John, United States Virgin Islands, USA.

Behavior

It is oviparous. The lizards shed their skin as they grow, and eat their old skins when they do so, perhaps to conserve the nutrients. Compared to some other species of anoles, this species is not so vocal, although it can make some chirping sounds.

As a defence against predators, they can autotomize their tails, and later grow a new replacement tail which gets longer each time they shed their skin. These new tails do not have the bony vertebrae of the original, and instead only have a rod of cartilage.

This growth of cartilage does not have the ability to autotomise, so in order to do the same trick again, an individual lizard must loose more and more of its tail vertebrae. Because the regrown tails of urban lizards contain on average a similar amount of vertebrae as those of the forests, this indicates that individual lizards loose their tail just as often in either habitat.

When looking for a mate or defending its territory, the males of many anole species may display their dewlap and perform "push-ups" to establish dominance. Males of many species may aggressively defend territories when mating, but only rarely does this result in physical combat. Like many anole species, this lizard can change colour from dark brown to tan -this is in response to emotions, rather than a method of camouflaging itself such as true chameleons.

Habitat

This anole is found in almost all habitats throughout Puerto Rico and the Virgin Islands, from open fields to rainforest, except some of the high altitude elfin forests in the mountainous regions of Puerto Rico. The species is found from sea level upwards, decreasing in abundance at higher elevations, with the animals having been found at maximum altitudes of 2,800 ft in the Reserva Forestal de Maricao as of 1988, and later 980 m in the Los Tres Picachos State Forest .

The introduced population in Costa Rica appears to prefer urban habitats, being mostly found on tree trunks or buildings in towns or cities, and rarely in more rural areas or in forests, and population on Dominica appears to have similar preferences. In general, introduced populations appear to strongly prefer, or be restricted to, urban and other disturbed areas. Anoles of this species found in the urban habitats of the cities of Puerto Rico are found to have lost and regrown their tails more often than those of the natural forests, this may be due to a higher density of urban predators such as house cats, or less places to escape predators, or might indicate urban predators are less accomplished at actually catching their prey. In some parks, such as Los Tres Picachos State Forest, it may be less common than species such as ''A. cuvieri'', ''A. evermanni'', ''A. gundlachi'' and ''A. stratulus''.

These lizards are "ground-trunk anoles", which is an "''Anolis'' ecomorph", and means that they spend the majority of their time on the bottom two meters of tree trunks, but will go to the ground to forage and also to lay eggs.

Food

In Puerto Rico this species has been photographed trying to gobble up quite large prey, such as the blindsnake ''Typhlops hypomethes'', as well as other anoles, such as a juvenile ''A. krugi''.

Predators

Henderson and Robert Powell record that this species may be eaten by another anole, ''A. cuvieri'', as well as the non-native mongoose, ''Herpestes javanicus'' and the bird ''Margarops fuscatus'', a thrasher. In a 2008 study of the reptilian components of the diets of Caribbean birds, Powell and Henderson record the birds of prey ''Buteo jamaicensis'' and ''Falco sparverius'' feeding on this anole. Rios-Lopez ''et al''. recorded in 2015 that the Puerto Rican endemic bird ''Todus mexicanus'', a species of tody known locally as ''San Pedrito'', eats this lizard.