Pachydermata (from two
Greek words παχύς
pachys, "thick" and δερμα
derma, "skin", meaning 'thick skin') is an obsolete
order of
mammals described by
Gottlieb Storr,
Georges Cuvier and others, at one time recognized by many systematists. Because it is
polyphyletic, the order is no longer in use, but it is important in the history of
systematics. Cuvier's Pachydermata included the three families of mammals he called Proboscidiana, Pachydermata Ordinaria, and Solipedes, all
herbivorous. They are now divided into the
Proboscidea, represented among living species only by
three species of elephants; the
Perissodactyla, or
odd-toed ungulates, including
horses,
tapirs and
rhinoceroses; the
Suina, or
pigs and
peccaries; the
Hippopotamidae; and the
Hyracoidea, or
hyraxes.