Abstract
UNTIL recently, the oldest known Arabo-African fossils of the elephant order (Proboscidea) were scarce Moeritherium-like remains from the Middle Eocene epoch of Mali1 and Senegal2. In 1984 the discovery in Algeria of Numidotherium koholense3 pushed back the record to the late Early Eocene. Here we report the discovery of a new genus in the late Palaeocene (Thanetian) epoch of Morocco (Ouled Abdoun Basin), about 7 million years older than Numidotherium. The new specimen is not only the oldest and smallest known proboscidean, but also the first modern ungulate from pre-Eocene strata. Though indirect data support an early eutherian radiation, close to the Cretaceous/Tertiary boundary, this is also among the very few known occurrences of modern placental orders before the Eocene. Unexpectedly, it belongs to what is, according to current phylogenetic studies4,5, one of the most derived eutherian orders, providing new evidence for a very early radiation of modern orders of placentals.