The Axillary Pit in Chameleons

The axillary pit in chameleons is a morphological feature located in the forelimb region, in the armpit. It is found e.g. in the genera Chamaeleo, Furcifer and Rhampholeon. 

In addition to serving as a taxonomic characteristic for species identification, the axillary pit can function as a mite pocket, providing a habitat for certain symbiotic or parasitic mites. These mites may interact with the chameleons in various ways, influencing their health or ecology.

The presence and morphology of the axillary pit contribute to the classification and understanding of relationships within chameleon species, e.g. it is a key diagnostic feature to separate the species of Furcifer lateralis group (F. lateralis, major and viridis)