Balaenoptera

Balaenoptera Temporal range: Neogene - recent PreЄ Є O S D C P T J K Pg N
Fin whale
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Cetacea
Suborder:	Mysticeti
Family:	Balaenopteridae
Subfamily:	Balaenopterinae
Genus:	Balaenoptera (Lacépède, 1804)

Balaenoptera, from the Latin balaena (whale) and pteron (fin), is a genus of Balaenopteridae, the rorquals, and contains eight extant species. The species Balaenoptera omurai was published in 2003.^[1] Balaenoptera is a diverse genus and comprises all but one of the extant species in its family - the other species is the humpback whale, Megaptera novaeangliae.

This genus is known in the fossil records from the Neogene to the Quaternary (age range: from 13.65 to 0.0 million years ago). ^[2]

Fossil of Balaenoptera acutorostrata cuvieri from Pliocene of Italy

Taxonomy

• Genus Balaenoptera^[1]
  • Balaenoptera acutorostrata, common minke whale
  • †Balaenoptera bertae (Pliocene, USA)
  • Balaenoptera bonaerensis, Antarctic minke whale
  • Balaenoptera borealis, sei whale
  • Balaenoptera brydei, Bryde's whale
  • †Balaenoptera cephalus
  • †Balaenoptera colcloughi (Pliocene, USA)
  • †Balaenoptera davidsonii (Pliocene, USA)
  • Balaenoptera edeni, Eden's whale
  • Balaenoptera musculus, blue whale
  • Balaenoptera omurai, Omura's whale
  • Balaenoptera physalus, fin whale
  • †Balaenoptera siberi (Pliocene, Peru)
  • †Balaenoptera sursiplana
  • †Balaenoptera taiwanica

Fossil species

Many fossil Balaenoptera species have been described. Some (namely "B. borealina", "B. definata", "B. emarginata", "B. gibbosa", "B. minutis", "B. rostratella", "B. sibbaldina", and "B. similis") are either nondiagnostic, highly fragmentary, or had no holotype specimen named, hence are considered nomina dubia. The species "Megaptera" hubachi may in fact be a species of Balaenoptera, and is certainly not a member of Megaptera.^[3][4] The valid fossil species of Balaenoptera are:

†Balaenoptera bertae

B. bertae is a relatively small species from the Upper Miocene to Upper Pliocene of California.^[5]

†Balaenoptera cephalus

B. cephalus was originally thought to be a species of Eschrichtius (gray whales) or Cetotherium, but more recent analysis shows it to be a member of Balaenoptera.^[6]

†Balaenoptera colcloughi

B. colcloughi is known from four specimens, including four skulls and some postcranial remains, found at the San Diego Formation. It was a close relative of Megaptera novaeangliae (the humpback whale), B. siberi, and B. physalus (the fin whale).^[7]

†"Balaenoptera" cortesii

"B." cortesii is a small species; it probably represents a distinct, unnamed genus of balaenopterid. A larger variant, called "B." cortesii var. portisi is probably also a distinct genus, and may be the same genus or species as Cetotheriophanes capellinii. The species "B. floridana" is indistinguishable from "B." cortesii var. portisi.^[3]

†Balaenoptera davidsonii

Like B. cephalus, B. davidsonii was originally classified under Eschrichtius, but it has since been moved to Balaenoptera. It was native to the Pliocene San Diego Formation. The only known fossil of B. davidsonii is a fragment of the left dentary.^[8]

†"Balaenoptera" ryani

"B" ryani represents genus of basal balaenopterid distinct from Balaenoptera.^[3]

†Balaenoptera siberi

B. siberi is known from two complete skeletons, its affinity with the genus Balaenoptera has been questioned.^[3][9]

†Balaenoptera sursiplana

B. sursiplana is a fragmentary species, based on a single fossil bulla.^[10]

†Balaenoptera taiwanica

Named after Taiwan, where the fossils were found, B. taiwanica is based on a single tympanic bone, which is similar to that of B. physalus, the fin whale.^[11]

References

1. "List of Marine Mammal Species and Subspecies". Society for Marine Mammalogy. Retrieved October 2013.
2. Fossilworks
3. Deméré; et al. (2005). "The Taxonomic and Evolutionary History of Fossil and Modern Balaenopteroid Mysticetes". Journal of Mammalian Evolution 12 (1-2): 99–143. doi:10.1007/s10914-005-6944-3.
4. M. Bisconti. 2007. A new basal balaenopterid whale from the Pliocene of northern Italy. Palaeontology 50(5):1103-1122
5. Boessenecker, Robert W. "A new marine vertebrate assemblage from the Late Neogene Purisima Formation in Central California, part II: Pinnipeds and Cetaceans." Geodiversitas 35.4 (2012): 815-940.
6. R. E. Weems and L. E. Edwards. 2007. The age and provenance of "Eschrichtius" cephalus Cope (Mammalia: Cetacea). Journal of Vertebrate Paleontology 27(3):752-756
7. Martin. (2014). From Finbacks to Humpbacks: Investigation of the Evolutionary History of Balaenopteridae.
8. T. Demere. 1986. The fossil whale, Balaenoptera davidsonii (Cope 1872), with a review of other Neogene species of Balaenoptera (Cetacea: Mysticeti). Marine Mammal Science 2(4):277-298
9. M. Bosselaers and K. Post. 2010. A new fossil rorqual (Mammalia, Cetacea, Balaenopteridae) from the Early Pliocene of the North Sea, with a review of the rorqual species described by Owen and Van Beneden. Geodiversitas 32(2):331-363
10. E. D. Cope. 1895. Fourth contribution to the marine fauna of the Miocene period of the United States. Proceedings of the American Philosophical Society 34:135-155
11. T. Huang. 1966. A new species of a whale tympanic bone from Taiwan, China. Transactions and Proceedings of the Paleontological Society of Japan 61:183-187