The brown anole (Anolis sagrei), also known commonly as the Cuban brown anole, or De la Sagra's anole, is a species of lizard in the family Dactyloidae. The species is native to Cuba and the Bahamas. It has been widely introduced elsewhere, via the importation and exportation of plants where the anole would lay eggs in the soil of the pots, and is now found in Florida and as far north in the United States as southern Georgia, Texas, Louisiana, Tennessee, Mississippi, Alabama, Hawaii, and Southern California.] It has also been introduced to other Caribbean islands, Mexico, and Taiwan.
This species is highly invasive. In its introduced range, it reaches exceptionally high population densities, is capable of expanding its range very quickly, and both outcompetes and consumes many species of native lizards, like the green anole. The brown anole's introduction into the United States in the early 1970s has altered the behavior and negatively affected populations of the native Carolina anole (Anolis carolinensis, also known as the green anole), which have since generally been relegated to the treetops.
The first record of the Anolis sagrei in Taiwan was in September 2000 at the Sanjiepu Township of Chiayi County. The source of the invasion was unknown. It was speculated that the egg from this animal is being hidden in potted plants heading to Taiwan and being introduced to Taiwan unintentionally. Wild groups are being discovered in the Ci Sing Tan Scenic Spot of the Hua-lian City in 2008. Monitoring removal plan was being carried out in 2009.
The brown anole is normally a light brown color with darker brown to black markings on its back, and several tan to light color lines on its sides. Like other anoles, it can change color, in this case a darker brown to black. Its dewlap ranges from yellow to orange-red.
Brown anoles are typically 5.0 to 8.5 inches long. The males can grow as large as their male Carolina anole counterparts, around 17.8–20.3 cm (7.0–8.0 in) long, with some individuals topping 22.9 cm (9.0 in). The females are also around the size of female Carolina anoles, which ranges from 7.6–15 cm (3.0–5.9 in). The male brown anole's head is smaller than that of the male Carolina anole.
The brown anole's tail has a ridge that travels all the way up to behind the head, a feature that the Carolina anole lacks. Female anolis lizards exhibit heritable polymorphism in their dorsal patterning. A study in Gainesville, Florida reported that one-third of A. sagrei females displayed a male-like chevron dorsal pattern, while other females had a striped dorsal pattern with continuous variation.