Aglaocetus

Aglaocetus is a genus of extinct baleen whales known from the Miocene of Patagonia, the US Eastern Seaboard, Japan and the Low Countries. It was once considered a member of Cetotheriidae along with many other putative cetotheres, but was recently recognized as representing a distinct family from true Cetotheriidae.

Aglaocetus Temporal range: Early-Late Miocene ~20.4–7.2 Ma PreꞒ Ꞓ O S D C P T J K Pg N
A. moreni skull
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Suborder:	Whippomorpha
Infraorder:	Cetacea
Superfamily:	Balaenopteroidea
Family:	†Aglaocetidae Steeman 2007
Genus:	†Aglaocetus Kellogg 1934
Species
A. latifrons (van Beneden 1880) A. longifrons (van Beneden 1880) A. moreni (Lydekker 1894) (type) A. rotundus (van Beneden 1880)
Synonyms
Amphicetus rotundus van Beneden 1880 Cetotherium moreni Lydekker 1894 Idiocetus longifrons Mesocetus latifrons Plesiocetus longifrons Plesiocetus latifrons

Species

Front view of A. moreni skull

There are three currently recognized valid species: Aglaocetus moreni, A. latifrons, and A. rotundus.^[1][2][3]

The type species, Aglaocetus moreni, was originally described as a species of Cetotherium, but later recognized as generically distinct from the latter.^[4] "Aglaocetus" patulus, described from the Calvert Formation by Remington Kellogg in 1968,^[5] was recovered by Bisconti et al. (2013) in a different phylogenetic position than the Aglaocetus type species.^[6] In 2020, A. patulus was renamed Atlanticetus.^[7]

Distribution

Fossils of Aglaocetus have been found in:^[8]

Miocene

• Gaimán Formation (Colhuehuapian-Santacrucian), Argentina
• Diest and Berchem Formations, Belgium
• Eibergen Member, Netherlands