described
Dorudon serratus based on a fragmentary maxilla and a few teeth found in South Carolina. He concluded that the teeth must have belonged to a mammal since they were two-rooted, that they must have been teeth from a juvenile since they were hollow, and also noted their similarity to the teeth then described for
Zeuglodon (
Basilosaurus). When exploring the type locality, Gibbes discovered a lower jaw and twelve caudal vertebrae, which he felt obliged to assign to
Zeuglodon together with his original material. Gibbes concluded that
Dorudon were juvenile
Zeuglodon and consequently withdrew his new genus. He did, however, allow
Louis Agassiz at Harvard to examine his specimens, and the Swiss professor replied that these were neither teeth of a juvenile nor those of
Zeuglodon, but of a separate genus just as Gibbes had first proposed. described
Prozeuglodon atrox (="Proto-
Basilosaurus") based on a nearly complete skull, a dentary and three associated vertebrae presented to him by the Geological Museum of Cairo. however, realized that Andrews' specimen was a juvenile, and, he assumed, the same species as
Zeuglodon isis, described by Andrews 1906. Kellogg also realized that the generic name
Zeuglodon was invalid and therefore recombined it
Prozeuglodon isis. Since then many specimens have been referred to
Prozeuglodon atrox, including virtually every part of the skeleton, and it has become obvious that it is a separate genus, not a juvenile "Proto-
Zeuglodon". Kellogg placed several of the species of
Zeuglodon described from Egypt in the early 20th century (including
Z. osiris,
Z. zitteli,
Z. elliotsmithii and
Z. sensitivius) in the genus
Dorudon. synonymized these four species and grouped them as
Saghacetus osiris.
D. serratus from Georgia and South Carolina in the United States. The
type species D. serratus was, and still is, based solely on two partial maxillae with a few teeth, cranial fragments, and a dozen vertebrae with some additional material, collected but not described by Gibbes, and referred to the type species. Before Uhen 2004,
D. atrox was based solely on Andrews holotype skull, lower jaw, and the vertebrae he referred to it, but is now the best-known archaeocete species. --> The two species of
Dorudon differ from other members of Dorudontinae mainly in size: they are considerably larger than
Saghacetus and slightly larger than
Zygorhiza, but also differ from both these genera in dental and/or cranial morphology. The limited known material for
D. serratus makes it difficult to compare the two species of
Dorudon. placed
D. atrox in the same genus as
D. serratus because of similarities in size and morphology, but kept them as separate species because of differences in dental morphology. Even though
D. serratus is the type species, the description of
Dorudon is largely based on
D. atrox because of its completeness. The cranial morphology of
D. atrox makes it distinct from all other archaeocetes. ==Description==