Balaenoptera siberi is an extinct species of

baleen whale Baleen whales (systematic name Mysticeti), also known as whalebone whales, are a parvorder of carnivorous marine mammals of the infraorder Cetacea (whales, dolphins and porpoises) which use keratinaceous baleen plates (or "whalebone") in their ...

from the

Late Miocene The Late Miocene (also known as Upper Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages. The Tortonian and Messinian stages comprise the Late Miocene sub-epoch, which lasted from 11.63 Ma (million ye ...

, described by Pilleri and Pilleri in 1989, based on fossils found in the

Pisco Formation The Pisco Formation is a geologic formation located in Peru, on the southern coastal desert of Ica, Peru, Ica and Arequipa. The approximately thick formation was deposited in the Pisco Basin, spanning an age from the Miocene, Middle Miocene up to ...

of the

Pisco Basin Pisco Basin ( es, Cuenca de Pisco) is a sedimentary basin extending over in southwestern Peru.Solís Mundaca, 2018, p.1 The basin has a thick sedimentary fill, which is about half the thickness of more northern foreland basins in Peru. The old ...

in southwestern Peru.Demeré et al., 2005, p.115

Description

The baleen whale fossils comprise a complete skeleton, including the skull, baleen, mandibles, flippers, and vertebral column. The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

fossils are housed in a private collection, belonging to Allejandro Pezzia Asserto, while a

paratype In zoology and botany, a paratype is a specimen of an organism that helps define what the scientific name of a species and other taxon actually represents, but it is not the holotype (and in botany is also neither an isotype nor a syntype). Of ...

is stored in the Staatliches Museum für Naturkunde in

Stuttgart Stuttgart (; Swabian: ; ) is the capital and largest city of the German state of Baden-Württemberg. It is located on the Neckar river in a fertile valley known as the ''Stuttgarter Kessel'' (Stuttgart Cauldron) and lies an hour from the ...

, Germany. The skull of the whale has a length of and a width of and intermediate in size between ''

Balaenoptera acutorostrata ''Balaenoptera'' () is a genus of rorquals containing eight extant species. ''Balaenoptera'' comprises all but two of the extant species in its family (the humpback whale and gray whale); the genus is currently polyphyletic, with the two afore ...

'' and '' B. borealis''.Demeré et al., 2005, p.116

Age

Fossils of the species were found in two different locations in the Pisco Formation; Aguada de Lomas,Aguada de Loma
at

Fossilworks Fossilworks is a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals ...

.org and Sacaco (SAO horizon).Sacaco (SAO horizon)
at

.org At time of description of the species, the sediments at Aguada de Loma ranged in age from the Late Miocene to

Late Pliocene Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, ...

,De Muizon & DeVries, 1985, p.552 with the layer the fossils were found dated to about 8 Ma (

Huayquerian The Huayquerian ( es, Huayqueriense) age is a period of geologic time (9.0–6.8 Ma) within the Late Miocene epoch of the Neogene, used more specifically within the SALMA classification. It follows the Mayoan and precedes the Montehermosan age. ...

). Subsequent dating of the sediments by Marx and Fordyce in 2015 gave a late Tortonian to early Messinian range of 7.0 to 8.0 Ma. The sediments at Sacaco were previously thought to be early

(3.9 Ma), while Ehret et al. in 2012 defined a

Messinian The Messinian is in the geologic timescale the last age or uppermost stage of the Miocene. It spans the time between 7.246 ± 0.005 Ma and 5.333 ± 0.005 Ma (million years ago). It follows the Tortonian and is followed by the Zanclean, the first ...

age of more than 5.75 Ma for this unit of the Pisco Formation.

Paleoecology

The Pisco Formation has provided many fossils of marine mammals, including several toothed whales (''

Acrophyseter ''Acrophyseter'' is a genus of extinct sperm whales that lived in the Late Miocene off the coast of Peru comprising two species: ''A. deinodon'' and ''A. robustus''. It is part of a group of macroraptorial sperm whales which all shared several f ...

'', '' Koristocetus'', '' Scaphokogia'', ''

Livyatan ''Livyatan'' is an extinct genus of macroraptorial sperm whale containing one known species: ''L. melvillei''. The genus name was inspired by the biblical sea monster Leviathan, and the species name by Herman Melville, the author of the famous ...

'' and more), other baleen whales (''

Incakujira ''Incakujira'' (meaning Inca whale) is a genus of rorqual whales that lived during the Late Miocene epoch in what are now the coasts of Peru, about 8 million to 7.3 million years ago. It contains a single species, ''Incakujira anillodefuego'', na ...

'', ''

Miocaperea ''Miocaperea'' is an extinct genus of pygmy right whale from the Miocene, Late Miocene Pisco Formation of Peru.Piscobalaena'', among others),

porpoise Porpoises are a group of fully aquatic marine mammals, all of which are classified under the family Phocoenidae, parvorder Odontoceti (toothed whales). Although similar in appearance to dolphins, they are more closely related to narwhals an ...

s ('' Lomacetus'' and '' Piscolithax''), seals (''

Hadrokirus ''Hadrokirus'' is an extinct genus of true seal ( Phocidae) that lived on the coast of Peru and North Carolina about 6 million years ago. The type species, ''H. martini'', was found in the Pisco Formation, together with other marine animals such ...

'', ''

Piscophoca ''Piscophoca'' is an extinct genus of pinniped. The genus was named after the fossiliferous Pisco Formation in Peru, where the holotype was found. Other fossils of the genus were found in the Bahía Inglesa Formation of the Caldera Basin in Chil ...

'' and '' Australophoca''), marine (''

Hemisyntrachelus ''Hemisyntrachelus'' is an extinct genus of cetacean.''Hemisyntrachelus''
at ...

'') and river dolphins ('' Brachydelphis'' and ''

Brujadelphis ''Brujadelphis'' is an extinct genus of river dolphin-like cetaceans of uncertain family placement from the Late Miocene epoch (Serravallian) of present-day Peru. The type species is ''Brujadelphis ankylorostris'', recovered from the Pisco Format ...

''), and the swimming sloth ''

Thalassocnus ''Thalassocnus'' is an extinct genus of semiaquatic ground sloths from the Miocene and Pliocene of the Pacific South American coast. It is monotypic within the subfamily Thalassocninae. The five species—''T. antiquus'', ''T. natans'', ''T. lit ...

''. Additionally, fossil penguins and other birds (such as ''

Pelagornis ''Pelagornis'' is a widespread genus of prehistoric pseudotooth birds. These were probably rather close relatives of either pelicans and storks, or of waterfowl, and are here placed in the order Odontopterygiformes to account for this uncertain ...

'') and shark teeth, among others of

megalodon Megalodon (''Otodus megalodon''), meaning "big tooth", is an extinct species of mackerel shark that lived approximately 23 to 3.6 million years ago (Mya), from the Early Miocene to the Pliocene epochs. It was formerly thought to be a member ...

, were found in the

fossiliferous A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

Pisco Formation.

References

Bibliography

* *

Description

Age

Paleoecology

References

Bibliography

Further reading