Lagenorhynchus

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.

There is compelling phylogenetic molecular evidence that the genus Lagenorhynchus is polyphyletic, in that it currently contains several species that are not closely related.{{Cite journal|last1=Vollmer|first1=Nicole L.|last2=Ashe|first2=Erin|last3=Brownell|first3=Robert L.|last4=Cipriano|first4=Frank|last5=Mead|first5=James G.|last6=Reeves|first6=Randall R.|last7=Soldevilla|first7=Melissa S.|last8=Williams|first8=Rob|date=2019|title=Taxonomic revision of the dolphin genus Lagenorhynchus|url=https://onlinelibrary.wiley.com/doi/abs/10.1111/mms.12573|journal=Marine Mammal Science|language=en|volume=35|issue=3|pages=957–1057|doi=10.1111/mms.12573|bibcode=2019MMamS..35..957V |s2cid=92421374|issn=1748-7692}}

{{Harvnb|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).{{Cite journal|last1=McGowen|first1=Michael R|last2=Tsagkogeorga|first2=Georgia|last3=Álvarez-Carretero|first3=Sandra|last4=dos Reis|first4=Mario|last5=Struebig|first5=Monika|last6=Deaville|first6=Robert|last7=Jepson|first7=Paul D|last8=Jarman|first8=Simon|last9=Polanowski|first9=Andrea|last10=Morin|first10=Phillip A|last11=Rossiter|first11=Stephen J|date=2019-10-21|title=Phylogenomic Resolution of the Cetacean Tree of Life Using Target Sequence Capture|url=https://doi.org/10.1093/sysbio/syz068|journal=Systematic Biology|volume=69|issue=3|pages=479–501|doi=10.1093/sysbio/syz068|issn=1063-5157|pmc=7164366|pmid=31633766}}

The remaining four species in the genus Lagenorhynchus—the Pacific white-sided dolphin, Peale's dolphin, hourglass dolphin and the dusky dolphin—are consistently placed within the Lissodelphininae subfamily, in studies of molecular phylogeny,{{Harvnb|May-Collado|Agnarsson|2006}} together with the right whale dolphin and the four species of the genus Cephalorhynchus (including Hector's dolphin). Some authors have suggested these four species be placed in the resurrected genus Sagmatias. However, other molecular studies place the hourglass and Peale's dolphins, phylogenetically, within the genus Cephalorhynchus and do not agree with inclusion in a new genus (together with Pacific white-sided dolphin and dusky dolphin).

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.{{Harvnb|Tougaard|Kyhn|2010}}{{Harvnb|Kyhn|Jensen|Beedholm|Tougaard|2010}} This signal is also used by porpoises (Phocoenidae) and the pygmy sperm whales (Kogiidae), but is not found among other dolphins. According to {{Harvnb|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|date=December 2021}}

The melon-headed whale was first classified as member of the genus Lagenorhynchus, but was later moved to its own genus, Peponocephala.{{cite journal |last1=Nishiwaki, M. and K.S. Norris |title=A new genus, Peponocephala, for the odontocete cetacean species (Electra electra) |journal=The Scientific Reports of the Whales Research Institute |date=1966 |volume=20 |pages=95–100}}

{{Reflist}}

{{Refbegin|30em}}

• {{Cite journal

| last1 = Kyhn | first1 = LA

| last2 = Jensen | first2 = FH

| last3 = Beedholm | first3 = FH

| last4 = Tougaard | first4 = J

| title = Echolocation in sympatric Peale's dolphins (Lagenorhynchus australis) and Commerson's dolphins (Cephalorhynchus commersonii) producing narrow-band high-frequency clicks

| date=June 2010 | journal = Journal of Experimental Biology | volume = 213 | issue = 11

| doi = 10.1242/jeb.042440 | issn = 0022-0949 | oclc = 618825118 | pmid = 20472781 | pages=1940–9| doi-access = free | bibcode = 2010JExpB.213.1940K

}}

• {{Cite journal

| last1 = LeDuc | first1 = R.G.

| last2 = Perrin | first2 = W.F.

| last3 = Dizon | first3 = A.E.

| title = Phylogenetic relationships among the delphinid cetaceans based on full cytochrome b sequences

| date=July 1999 | journal = Marine Mammal Science | volume = 15 | issue = 3

| pages = 619–648

| doi = 10.1111/j.1748-7692.1999.tb00833.x | bibcode = 1999MMamS..15..619L

| issn = 0824-0469 }}

• {{Cite journal

| last1 = May-Collado | first1 = Laura

| last2 = Agnarsson | first2 = Ingi

| title = Cytochrome b and Bayesian inference of whale phylogeny

| year = 2006 | journal = Molecular Phylogenetics and Evolution | volume = 38 | pages = 344–54

| url = http://www.theridiidae.com/uploads/6/6/8/0/6680387/maycolladoandagnarsson2006.pdf

| doi = 10.1016/j.ympev.2005.09.019 | issn = 1055-7903 | oclc = 441745572 | pmid=16325433 | issue=2| bibcode = 2006MolPE..38..344M

}}

• {{Cite journal

| last1 = Schevill | first1 = W.E.

| last2 = Watkins | first2 = W.A.

| title = Pulsed sounds of the porpoise Lagenorhynchus australis

| date = January 15, 1971 | journal = Breviora | volume = 366 | pages = 1–10

| oclc = 80876226 | issn = 0006-9698 }}

• {{Cite journal

| last1 = Tougaard | first1 = J

| last2 = Kyhn | first2 = LA

| title = Echolocation sounds of hourglass dolphins (Lagenorhynchus cruciger) are similar to the narrow band high-frequency echolocation sounds of the dolphin genus Cephalorhynchus

| year = 2010 | journal = Marine Mammal Science | volume = 26 | issue = 1 | pages = 239–45

| doi = 10.1111/j.1748-7692.2009.00307.x | issn = 0824-0469 | oclc = 497138903 | doi-access = free | bibcode = 2010MMamS..26..239T

}}

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{{Cetacea|O.}}

{{Odontoceti|D.}}

{{Taxonbar|from=Q837606}}

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Category:Cetacean genera

Category:Animals that use echolocation

Category:Taxa named by John Edward Gray