Femoral pore

Femoral pores are a part of a holocrine secretory gland found on the inside of the thighs of certain lizards and amphisbaenians which releases pheromones to attract mates or mark territory.

[1] Femoral pores appear as a series of pits or holes within a row of scales on the ventral portion of the animal's thigh.

Femoral pores are present in all genera in the families Cordylidae, Crotaphytidae, Hoplocercidae, Iguanidae, Phrynosomatidae, and Xantusiidae.

[3] According to tests performed on the Green iguana, the variation in the chemicals released by the femoral pores can help to determine age, sex, and individual identity of the animal in question.

[2] For example, the number of pores in male lizards of the family Lacertidae can range between zero (e.g. Meroles anchietae) and 32 (e.g. Gallotia galloti) per limb.

Femoral pores on a gecko
Femoral pores on a male Western Fence Lizard secreting waxy lipids. These lipids are used by the male to lay down scent for marking territory or other purposes.
Evolution of femoral (epidermal) pores in lizards: a family overview. Pie charts from the maximum likelihood analyses are shown for ancestors, with the proportion of black representing the likelihood of epidermal pores being present in this ancestor. [ 2 ]