Basilosauridae

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Basilosauridae
Temporal range: Late Eocene[1]
Saghacetus osiris 2.JPG
Saghacetus osiris
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Suborder: Archaeoceti
Family: Basilosauridae
Cope 1868[1]
Genera

See text

Basilosauridae is a paraphyletic family of extinct cetaceans that lived during the late middle to the early late Eocene,[2] known from all continents including Antarctica.[1][3] They were probably the first fully aquatic cetaceans.[2]

Characteristics[edit]

Dorudon atrox skeleton

Basilosaurids ranged in size from 4 to 16 m (13 to 52 ft). Like all archaeocetes, they lacked the telescoping skull of modern whales. Their dentition is easily distinguishable from that of other archaeocetes: they lack upper third molars and the upper molars lack protocones, trigon basins, and lingual third roots. The cheek teeth have well-developed accessory denticles. The hindlimbs are strongly reduced and does not articulate with the vertebral column which lack true sacral vertebrae.[2]

Basilosaurid forelimbs have broad and fan-shaped scapulae attached to a humerus, radius, and ulna which are flattened into a plane to which the elbow joint was restricted, effectively making pronation and supination impossible. Because of a shortage of forelimb fossils from other arachaocetes, it is not known if this arrangement is unique to basilosaurids. Some of the characteristics of basilosaurids are also present in Georgiacetus.[2]

Taxonomy[edit]

See also[edit]

Notes[edit]

References[edit]