Flap-necked Chameleon

The flap-necked chameleon (Chamaeleo dilepis) is a medium-sized to large African chameleon that can reach about 35 cm in total length. Its most distinctive feature is the pair of movable occipital flaps behind the head. A pale stripe or series of light patches along the side of the body is also typical, although colour and pattern vary considerably among individuals and populations.

Like other chameleons, it has independently moving eyes, grasping feet and a prehensile tail that together make it highly adapted for moving slowly through shrubs and trees. Females are generally larger than males in southern African populations.

The flap-necked chameleon belongs to a taxonomically unresolved species complex. Genetic work published in 2022 found three distinct lineages within Chamaeleo dilepis that may represent separate species, but these corresponded poorly with the eight subspecies traditionally recognised.

There is not yet sufficient evidence to formally split these lineages into separate species. A 2026 review likewise concluded that a recently proposed species had not been sufficiently distinguished from the other forms to justify recognition as a separate species, and returned roperi and martensi to subspecies rank within C. dilepis. The species therefore remains treated as a single species in the Reptile Database, but with substantial unresolved geographic variation.

Flap-necked chameleons are strongly associated with savanna, open woodland, bushland and other relatively open habitats with shrubs and trees. They also occur along forest edges and in some rural and urban vegetation.

The species is primarily arboreal, but individuals regularly descend to the ground to cross between vegetation patches. A study published in 2020 at Telperion Nature Reserve in South Africa found that the height and type of vegetation used changes through the year with temperature, rainfall and plant structure.

Arthropods dominate the diet. A study published in 2012 from southern Africa found grasshoppers, crickets and other orthopterans to be especially important both numerically and by volume, followed by beetles.

A wide range of other insects and arthropods are also taken. Vertebrates are very rare prey, but both a skink and a gecko have been found in stomach contents, and occasional cannibalism has also been documented. Prey size and availability change with season and with the vegetation being used.

Each eye can scan much of the surroundings independently while the chameleon remains almost motionless. When a potential prey item is selected, the eyes converge on it to provide precise distance information.

The sticky tongue is then projected rapidly toward the target and can capture prey well beyond the reach of the jaws. This sit-and-wait technique allows the chameleon to hunt efficiently without making the conspicuous movements that would reveal it to prey or predators.

Flap-necked chameleons are diurnal and mostly solitary. Slow movement, cryptic posture and colour help them remain inconspicuous, while basking and shifts between sun and shade are used to regulate body temperature.

Colour change serves several functions. Temperature, light, stress and social context can all alter colour and pattern. Darker colours can increase absorption of solar radiation, while highly contrasting patterns are used during encounters with rivals or potential mates.

The paired flaps behind the head are also part of the display system. A threatened chameleon or an individual confronting a rival can raise them, flatten or enlarge the body and change colour to appear more imposing.

In southern Africa, reproduction is concentrated mainly in spring and summer. A museum-based study published in 2012 found that females were larger than males and that larger females produced larger clutches. This may help explain why larger body size has evolved in females.

In the same study, mean clutch size was 44.2 eggs, with 19–74 recorded. The female descends to the ground and excavates a tunnel about 15–30 cm deep in damp soil before laying and covering the eggs. Embryonic development is very slow: the eggs overwinter with a period of embryonic diapause, a temporary pause in embryonic development, and in the wild hatching can take up to 377 days. This delay helps time emergence of the young to more favourable conditions. The hatchlings receive no parental care.

The flap-necked chameleon has long been part of the international live-reptile trade and is listed in CITES Appendix II, so international commercial trade is regulated. Wild collection has historically been especially important in parts of East Africa.

A 2024 analysis of international chameleon trade found that reported trade in wild-sourced animals declined substantially between 2000 and 2019 while captive-bred trade increased. Illegal or poorly documented trade nevertheless continues.

The flap-necked chameleon is classified as least concern on the IUCN Red List, reflecting its very broad range, local abundance and tolerance of some modified habitats.

The assessment treats the widespread complex as a single species. Genetic studies nevertheless reveal substantial cryptic diversity—genetically distinct lineages that look very similar—and if some of these are later recognised as separate species, they may have much smaller ranges than C. dilepis as currently defined.