The giant armadillo (Priodontes maximus) can grow up to 40 inches, measured from the tip of the nose to the base of the tail, which can be about half of his overall length. Considerably larger than the American nine-banded armadillo, the giant armadillo lives exclusively in South America. From a distance, males and females appear identical, but close physical observation, including that of their behavior, can tip you off to which is which.
There is a minimal size difference between male and female armadillos -- although males may be slightly larger -- and no distinct traits to differ between the sexes when you view them from above. The difference becomes apparent when turned on their backs. Males have among the longest penes of any mammal for their size, extending up to two-thirds of the body's length. Females have two mammary glands to feed their young.
Nothing in an armadillo's generally solitary existence gives a clue to their gender. When a male and female come together, their rather unremarkable courtship consists mainly of the male following the female around until she allows him to mount her from behind, fertilizing her single egg with his long penis. The single egg splits into multiple offspring, each baby genetically identical to the others. The male will depart to pursue other females, leaving the female to care for the young on her own.
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