Phylogenetic Tree of Camelids

Suborder Tylopoda 

Representatives of the suborder Tylopoda (meaning “swollen foot”) have some unique intrinsic characteristics. Instead of hooves, they have two-toed feet with blunt curved claws, and they are bearing their weight on the pads of the feet rather than on toes which is typical for many other mammals. They owe their name to the springy calloused pads on the soles of their feet. In the llamas each toe has its own pad, while in the camels this pad is not separated and camel tracks look like a chain of the solid round marks. The typopods look quite clumsy: they have very long legs and neck, and relatively small head with elongated snout and split upper lip. However, it all does not prevent them from running at a speed of up to 55 km/h – though these animals’ trait is presented by ambling, when the front and hind legs on the same side of the body move synchronically, in the same direction at the same time. All tylopods have three-chambered stomach. Another unique feature that differs from what is seen in other mammals is the shape of their red blood cells that are ellipsoidal rather than disk-shaped.

This suborder (that is sometimes referred to as a separate order) has only one extant family, Camelids, which includes three genera and six species presented by the camels of the Old World and their South American relatives – llamas and vicuñas.