Small coastal dolphins endemic to south-eastern Australia have variously been assigned to described species Tursiops truncatus, T. aduncus or T. maugeanus; however the specific affinities of these animals is controversial and have recently been questioned. Historically ‘the southern Australian Tursiops’ was identified as unique and was formally named Tursiops maugeanus but was later synonymised with T. truncatus. Morphologically, these coastal dolphins share some characters with both aforementioned recognised Tursiops species, but they also possess unique characters not found in either. Recent mtDNA and microsatellite genetic evidence indicates deep evolutionary divergence between this dolphin and the two currently recognised Tursiops species. However, in accordance with the recommendations of the Workshop on Cetacean Systematics, and the Unified Species Concept the use of molecular evidence alone is inadequate for describing new species. Here we describe the macro-morphological, colouration and cranial characters of these animals, assess the available and new genetic data, and conclude that multiple lines of evidence clearly indicate a new species of dolphin. We demonstrate that the syntype material of T. maugeanus comprises two different species, one of which is the historical ‘southern form of Tursiops’ most similar to T. truncatus, and the other is representative of the new species and requires formal classification. These dolphins are here described as Tursiops australis sp. nov., with the common name of ‘Burrunan Dolphin’ following Australian aboriginal narrative. The recognition of T. australis sp. nov. is particularly significant given the endemism of this new species to a small geographic region of southern and south-eastern Australia, where only two small resident populations in close proximity to a major urban and agricultural centre are known, giving them a high conservation value and making them susceptible to numerous anthropogenic threats.
References
[1]
Steeman ME, Hebsgaard MB, Fordyce RE, Ho SYW, Rabosky DL, et al. (2009) Radiation of Extant Cetaceans Driven by Restructuring of the Oceans. Systematic Biology 58: 573–585.
[2]
Caballero S, Trujillo F, Vianna JA, Barrios-Garrido H, Montiel MG, et al. (2007) Taxonomic status of the genus Sotalia: Species level ranking for “tucuxi” (Sotalia fluviatilis) and “costero” (Sotalia guianensis) dolphins. Marine Mammal Science 23: 358–386.
[3]
Beasley I, Robertson KM, Arnold P (2005) Description of a new dolphin, the Australian Snubfin dolphin Orcaella heinsohni sp. n. (Cetacea, Delphinidae). Marine Mammal Science 21: 365–400.
[4]
Kingston SE, Adams LD, Rosel PE (2009) Testing mitochondrial sequence and anonymous nuclear markers for phylogeny reconstruction in a rapidly radiating group: molecular systematics of the Delphininae (Ceatcea: Odontoceti: Delphinidae). BMC Evolutionary Biology 9: 245.
[5]
LeDuc RG, Perrin WF, Dizon AE (1999) Phylogenetic relationships among the delphinid cetaceans based on full cytochrome b sequences. Marine Mammal Science 15: 619–648.
[6]
May-Collado L, Agnarsson I (2006) Cytochrome b and Bayesian inference of whale phylogeny. Molecular Phylogenetics and Evolution 38: 344–354.
[7]
Tezanos-Pinto G, Baker CS, Russell K, Martien K, Baird RW, et al. (2009) A Worldwide Perspective on the Population Structure and Genetic Diversity of Bottlenose Dolphins (Tursiops truncatus) in New Zealand. Journal of Heredity 100: 11–24.
[8]
Appeltans W, Bouchet P, Boxshall GA, Fauchald K, Gordon DP, et al. (2011) World Register of Marine Species. Accessed at http://www.marinespecies.org.
[9]
Wang JY, Chou L-S, White BN (1999) Mitochondrial DNA analysis of sympatric morphotypes of bottlenose dolphins (genus: Tursiops) in Chinese waters. Molecular Ecology 8: 1603–1612.
[10]
Wang JY, Chou LS, White BN (2000) Osteological differences between two sympatric forms of bottlenose dolphins (genus Tursiops) in Chinese waters. Journal of Zoology 252: 147–162.
[11]
Wang JY, Chou L-S, White BN (2000) Differences in the external morphology of two sympatric species of bottlenose dolphins (genus Tursiops) in the waters of China. Journal of Mammalogy 81: 1157–1165.
[12]
Natoli A, Peddemors VM, Hoelzel AR (2004) Population structure and speciation in the genus Tursiops based on microsatellite and mitochondrial DNA analyses. Journal of Evolutionary Biology 17: 363–375.
[13]
Charlton K, Taylor AC, McKechnie SW (2006) A note on divergent mtDNA lineages of bottlenose dolphins from coastal waters of southern Australia. Journal of Cetacean Research & Management 8: 173–179.
[14]
M？ller LM, Bilgmann K, Charlton-Robb K, Beheregaray L (2008) Multi-gene evidence for a new bottlenose dolphin species in southern Australia. Molecular Phylogenetics and Evolution 49: 674–681.
[15]
Caballero S, Jackson J, Mignucci-Giannoni AA, Barrios-Garrido H, Beltran-Pedreros S, et al. (2008) Molecular systematics of South American dolphins Sotalia: Sister taxa determination and phylogenetic relationships, with insights into a multi-locus phylogeny of the Delphinidae. Molecular Phylogenetics and Evolution 46: 252–268.
[16]
Ross GJB, Cockcroft VG (1990) Comments on Australian Bottlenose Dolphins and the Taxonomic Status of Tursiops aduncus (Ehrenberg, 1832). In: Leatherwood S, Randall RR, editors. The Bottlenose Dolphin. London, UK: Academic Press. pp. 101–128.
[17]
M？ller LM, Beheregaray LB (2001) Coastal bottlenose dolphins from southeastern Australia are Tursiops aduncus according to sequences of the mitochondrial DNA control region. Marine Mammal Science 17: 249–263.
[18]
Krützen M, Sherwin WB, Berggren P, Gales N (2004) Population structure in an inshore cetacean revealed by microsatellite and mtDNA analysis: Bottlenose dolphins (Tursiops sp.) in Shark Bay, Western Australia. Marine Mammal Science 20: 28–47.
[19]
Scott HH, Lord CE (1919) Studies of Tasmanian Cetacea. Pt 1. Papers and Proceedings of the Royal Society of Tasmania 1–17.
[20]
Kemper CM (2004) Osteological variation and taxonomic affinities of bottlenose dolphins, Tursiops spp., from South Australia. Australian Journal of Zoology 52: 29–48.
[21]
Iredale T, Troughton E (1934) A check-list of the mammals recorded from Australia. Memoirs of the Australian Museum 6: 1–122.
[22]
Perrin W (2009) World Cetacea Database. http://www.marinespecies.org/cetacea.
[23]
Australian Faunal Directory (2008) Species Tursiops truncatus. http://www.environment.gov.au/biodiversi？ty/abrs/online-resources/fauna/afd/taxa/？Tursiops_truncatus.
[24]
Hale PT (2002) Interactions between vessels and dolphins in Port Phillip Bay. Melbourne, Victoria: Department of Natural Resources and Environment.
[25]
Scarpaci C, Bigger SW, Saville TA, Nugegoda D (2000) The Bottlenose Dolphin Tursiops truncatus in the southern end of Port Phillip Bay: Behavioural characteristics in Spring and Summer. Victorian Naturalist 117: 4–9.
[26]
Warren-Smith áB, Dunn WL (2006) Epimeletic Behaviour Toward a Seriously Injured Juvenile Bottlenose Dolphin (Tursiops sp.) in Port Phillip, Victoria, Australia. Aquatic Mammals 32: 357–362.
[27]
Owen K, Charlton-Robb K, Thompson R (2011) Resolving the trophic relations of cryptic species: An example using stable isotope analysis of dolphin teeth. PLoS ONE 6: e16457.
[28]
Pichler FB, Robineau D, Goodall RNP, Meyer MA, Olivarria C, et al. (2001) Origin and radiation of Southern Hemisphere coastal dolphins (genus Cephalorhynchus). Molecular Ecology 10: 2215–2223.
[29]
Reeves RR, Perrin WF, Taylor BL, Baker CS, Mesnick SL (2004) Report of the workshop on shortcomings of cetacean taxonomy in relation to needs of conservation and management. La Jolla, CA: Southwest Fisheries Science Centre. U.S. Department of Commerce. 94 p.
[30]
De Queiroz K (2007) Species Concepts and Species Delimitation. Systematic Biology 56: 879–886.
[31]
Cipriano F, Rosel PE, Taylor BL, Hancock B, Robertson KM (2009) Using Genetic Evidence for recognizing Marine Mammal Subspecies. Quebec City, Canada.
[32]
Wang JY, Chou L-S, White BN (2000) Osteological differences between two sympatric forms of bottlenose dolphins (genus Tursiops) in Chinese waters. Journal of Zoology (London) 252: 147–162.
[33]
Hale PT, Barreto AS, Ross GJB (2000) Comparative morphology and distribution of the aduncus and truncatus forms of bottlenose dolphin Tursiops in the Indian and Western Pacific Oceans. Aquatic Mammals 26: 101–110.
[34]
Perrin WF, Robertson KM, Van Bree PJH, Mead JG (2007) Cranial description and genetic identity of the holotype specimen of Tursiops aduncus (Ehrenberg, 1832). Marine Mammal Science 23: 343–357.
[35]
Inc. SS (2009) SYSTAT 13 for Windows Bangalore, India. Cranes Software International Ltd.
[36]
Hammer O, Harper DAT, Ryan PD (2001) PAST: Paleontological statistic software package for education and data analysis. 1.94b ed: Paleontologia Electronica 1(4): 9.
[37]
Suetin G, White BN, Boag PT (1991) Preservation of avian blood and tissue samples for DNA analysis. Canadian Journal of Zoology 69: 82–91.
[38]
Krützen M, Barre LM, M？ller LM, Heithaus MR, Simms C, et al. (2002) A biopsy system for small cetaceans: Darting success and wound healing in Tursiops spp. Marine Mammal Science 18: 863–878.
[39]
Weber LI, Luca MJ, Barreto AS, Souza TT (2007) Successful Amplification of Mitochondrial DNA from Dentin of the Bottlenose Dolphin Tursiops truncatus. Brazilian Archives of Biology and Technology 50: 11–19.
[40]
Shibata Y, Fujita S, Takahashi H, Yamaguchi A, Koji T (2000) Assessment of decalcifying protocols for detection of specific RNA by non-radioactive in situ hybridization in calcified tissues. Histochem Cell Biol 113: 153.
[41]
Cooper A, Poinar H (2000) Ancient DNA: Do It Right or Not at All. Science 289: 1139.
[42]
Boessenkool S, Austin JJ, Worthy TH, Scofield P, Cooper A, et al. (2008) Relict or colonizer? Extinction and range expansion of penguins in southern New Zealand. Proceedings Royal Society Biology.
[43]
Tamura K, Peterson D, Peterson N, Stecher G, Nei M, et al. (2011) MEGA5: Molecular Evolutionary Genetics Analysis using Maximum Likelihood, Evolutionary Distance, and Maximum Parsimony Methods. Molecular Biology and Evolution. in press.
[44]
Hasegawa M, Kishino H, Yano T (1985) Dating the human-ape split by a molecular clock of mitochondrial DNA. Journal of Molecular Evolution 22: 160–174.
[45]
Swofford DL (2003) PAUP*. Phylogenetic analysis using parsimony (*and other methods). Version 4b 10 ed: Sinauer Associates, Sunderland, MA.
Thomas W (1834) William Thomas Papers, Manuscript 214. William Thomas Papers, Manuscript 214:
[48]
Bilgmann K, M？ller LM, Harcourt RG, Gibbs SE, Beheregaray LB (2007) Genetic differentiation in bottlenose dolphins from South Australia: association with local oceanography and coastal geography. Marine Ecology-Progress Series 341: 265–276.
[49]
Hare MP, Cipriano F, Collins AG, Palumbi SR (2002) Genetic evidence on the demography of speciation in allopatric dolphin species. Evolution 56: 804–816.
[50]
Rosel PE, Dizon AE, Heyning JE (1994) Gentic analysis of sympatric morphotypes of common dolphins (genus Delphinus). Marine Biology 119:
[51]
Kingston SE, Rosel PE (2004) Genetic differentiation among recently diverged delphinid taxa determined using AFLP markers. Journal of Heredity 95: 1–10.
[52]
Lyons LA, Laughlin TF, Copeland NG, Jenkins NA, Womack JE, et al. (1997) Comparative anchor tagged sequences (CATS) for integrative mapping of mammalian genomes. Nature Genetics 15: 47–56.
