Lagenorhynchus

Lagenorhynchus Temporal range: Pliocene to Recent [1]
Lagenorhynchus albirostris
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Suborder:	Whippomorpha
Infraorder:	Cetacea
Family:	Delphinidae
Genus:	Lagenorhynchus Gray, 1846
Type species
Delphinus albirostris [2] Gray, 1846
Species
Lagenorhynchus albirostris

Lagenorhynchus is a genus of oceanic dolphins in the infraorder Cetacea, that formerly contained six extant species. ^[3] However, there was consistent molecular evidence that the genus is polyphyletic ^[4] and several of the species moved to other genera, leaving only the white-beaked dolphin in this genus among extant species. ^[5] In addition, the extinct species Lagenorhynchus harmatuki is also classified in this genus. ^[6]

Etymology

The name Lagenorhynchus derives from the Greek lagenos meaning "bottle" and rhynchus meaning "beak". Indeed, the "bottle-nose" is a characteristic of this genus. However, the dolphins popularly called bottlenose dolphins belong in the genus Tursiops .

Taxonomy

For a long time there was compelling phylogenetic molecular evidence that the genus Lagenorhynchus is polyphyletic, in that it contained several species that are not closely related. ^[7] LeDuc, Perrin & Dizon 1999 found that white-beaked and Atlantic white-sided dolphins are phylogenetically isolated within the Delphinidae, where they are believed to be rather basal members of the family, along with the orca (subfamily Orcininae). ^[8] This was confirmed in 2025 by Galatius, et al. ^[9]

As a result, in 2025 most of the species previously placed in Lagenorhynchus were moved to other genera, leaving it as a monotypic genus containing only the white-beaked dolphin. ^[5] Other species previously included in Lagenorhynchus were moved to: ^[5]

• Atlantic white-sided dolphin Leucopleurus acutus
  
• Pacific white-sided dolphin Aethalodelphis obliquidens
  
• Dusky dolphin Aethalodelphis obscurus
  
• Peale's dolphin Cephalorhynchus australis
  
• Hourglass dolphin Cephalorhynchus cruciger
  

This phylogeny is supported by acoustic and morphological data; both the hourglass and Peale's dolphins share, with the other species of Cephalorhynchus, a distinctive type of echolocation signal known as a narrow-band/high-frequency signal. ^{[10] [11]} This signal is also used by porpoises (Phocoenidae) and the pygmy sperm whales (Kogiidae), but is not found among other dolphins. According to Schevill & Watkins 1971, Peale's dolphin, and the other Cephalorhynchus species, are the only dolphins that do not "whistle"; presumably, this would be the case for hourglass dolphins, as well. Peale's dolphin also shares with several Cephalorhynchus species the possession of a distinct white marking behind the pectoral (“armpit”) fin.^{[ citation needed ]}

The melon-headed whale was first classified as member of the genus Lagenorhynchus, but was later moved to its own genus, Peponocephala. ^[12]

Notes

1. "Fossilworks: Lagenorhynchus".
2. Wilson, D. E.; Reeder, D. M., eds. (2005). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore: Johns Hopkins University Press. ISBN   978-0-8018-8221-0. OCLC   62265494.
3. "List of marine mammal species". Society for Marine Mammalogy. 13 November 2016. Retrieved 30 December 2021.
4. LeDuc, Perrin & Dizon 1999
5. "List of Marine Mammal Species and Subspecies". Marine Mammal Science Taxonomy Committee. 13 November 2016. Retrieved 2025-07-17.
6. "Fossilworks: Lagenorhynchus harmatuki". fossilworks.org. Retrieved 17 December 2021.
7. Vollmer, Nicole L.; Ashe, Erin; Brownell, Robert L.; Cipriano, Frank; Mead, James G.; Reeves, Randall R.; Soldevilla, Melissa S.; Williams, Rob (2019). "Taxonomic revision of the dolphin genus Lagenorhynchus" . Marine Mammal Science. 35 (3): 957–1057. Bibcode:2019MMamS..35..957V. doi:10.1111/mms.12573. ISSN   1748-7692. S2CID   92421374.
8. McGowen, Michael R; Tsagkogeorga, Georgia; Álvarez-Carretero, Sandra; dos Reis, Mario; Struebig, Monika; Deaville, Robert; Jepson, Paul D; Jarman, Simon; Polanowski, Andrea; Morin, Phillip A; Rossiter, Stephen J (2019-10-21). "Phylogenomic Resolution of the Cetacean Tree of Life Using Target Sequence Capture". Systematic Biology. 69 (3): 479–501. doi:10.1093/sysbio/syz068. ISSN   1063-5157. PMC   7164366 . PMID   31633766.
9. Galatius, Anders; Kinze, Carl; Olsen, Morten; Tougaard, Jakob; Gotzek, Dietrich; McGowen, Michael (April 2025). "Phylogenomic, morphological and acoustic data support a revised taxonomy of the lissodelphinine dolphin subfamily". Molecular Phylogenetics and Evolution. 205. doi:10.1016/j.ympev.2025.108299.
10. Tougaard & Kyhn 2010
11. Kyhn et al. 2010
12. Nishiwaki, M. and K.S. Norris (1966). "A new genus, Peponocephala, for the odontocete cetacean species (Electra electra)". The Scientific Reports of the Whales Research Institute. 20: 95–100.

References

• Kyhn, LA; Jensen, FH; Beedholm, FH; Tougaard, J (June 2010). "Echolocation in sympatric Peale's dolphins (Lagenorhynchus australis) and Commerson's dolphins (Cephalorhynchus commersonii) producing narrow-band high-frequency clicks". Journal of Experimental Biology. 213 (11): 1940–9. Bibcode:2010JExpB.213.1940K. doi: 10.1242/jeb.042440 . ISSN   0022-0949. OCLC   618825118. PMID   20472781.
• LeDuc, R.G.; Perrin, W.F.; Dizon, A.E. (July 1999). "Phylogenetic relationships among the delphinid cetaceans based on full cytochrome b sequences". Marine Mammal Science. 15 (3): 619–648. Bibcode:1999MMamS..15..619L. doi:10.1111/j.1748-7692.1999.tb00833.x. ISSN   0824-0469.
• May-Collado, Laura; Agnarsson, Ingi (2006). "Cytochrome b and Bayesian inference of whale phylogeny" (PDF). Molecular Phylogenetics and Evolution. 38 (2): 344–54. Bibcode:2006MolPE..38..344M. doi:10.1016/j.ympev.2005.09.019. ISSN   1055-7903. OCLC   441745572. PMID   16325433.
• Schevill, W.E.; Watkins, W.A. (January 15, 1971). "Pulsed sounds of the porpoise Lagenorhynchus australis". Breviora. 366: 1–10. ISSN   0006-9698. OCLC   80876226.
• Tougaard, J; Kyhn, LA (2010). "Echolocation sounds of hourglass dolphins (Lagenorhynchus cruciger) are similar to the narrow band high-frequency echolocation sounds of the dolphin genus Cephalorhynchus". Marine Mammal Science. 26 (1): 239–45. Bibcode:2010MMamS..26..239T. doi: 10.1111/j.1748-7692.2009.00307.x . ISSN   0824-0469. OCLC   497138903.