The paired copulatory organs lying laterally in a cavity in the base of the tail in snakes and lizards (Peters 1964).
Paired sex organs of males, the bulge at the base of the tail
Penis of snake. Each snake has two penises, each of which is an independent fully functioning unit. Only one is used during mating. Each hemipene is sac-like and lies internally on either side of the base of the tail behind the vent in its own individual sheath. During mating the one that will be used is everted through an opening in the sheath and turned inside out. Hemipenes are covered by spines and hooks that help keep them in place during mating. A groove on the ventral boarder acts as a channel for sperm transfer.
male copulatory organs: paired in squamates, unpaired in crocodilians and turtles
A male iguana's copulatory organs. Males do not have a single penis, but rather two hemipenes, that deliver sperm to the female's body during copulation. Hemipenes are often seen protruding from the vent (see below) during or after mating or other sexual activity. Hemipenes may also be visible during defecation, and may occasionally remain outside the body in what is known as a prolapse (see below). To see a photo of hemipenes, visit our Breeding Season Issues or Anatomy pages.
The bi-lobed male reproductive organ that is kept inverted in the base of the tail until needed for copulation.
The hemipenes is the male reptiles reproduction organ.
Paired, eversible copulatory organs in male snakes and lizards.