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TURSIOPS EREBENNUS (COPE, 1865) Synonymy: Delphinus erebennus Cope, 1865; Tursiops subridens True, 1884. Suggested common name: Tamanend’s bottlenose dolphin. Etymology: The generic name, Tursiops, derived from Latin Tursio (Latin), a dolphin-like fish in Pliny’s Natural History, originally from thyrsiōn (Greek). The suffix - ops (Greek) is a reference to the face or appearance. For the species epithet, erebennus, Cope did not provide an etymology, but he mentioned an apparently darker coloration (Cope, 1865: 281). Thus, his use of erebennus might reference Erebus or Erebos, (Ἔρεβος) a Greek mythological primordial deity representing deep darkness or shadow. The English common name references Chief Tamanend (1628– 1701) of the Turtle Clan of the Nanticoke LenniLenape Tribal Nation. Chief Tamanend (‘The Affable’) was known for his wisdom and peaceful nature, and he signed a series of peace treaties with William Penn (founder of the Province of Pennsylvania), starting in 1683. The Nanticoke Lenni-Lenape Tribal Nation is formed by the descendants of the Lenni-Lenape Tribe and the Nanticoke Tribe, the original people to inhabit the lands between south-eastern New York and Delmarva Peninsula, including all of New Jersey, eastern Pennsylvania and Delaware Bay, the region where the holotype of Tursiops erebennus was found. This common name was chosen in consultation with representatives of the Nanticoke Lenni-Lenape Tribal Nation. Holotype and type locality: Physically mature (incomplete) postcranial skeleton (Fig. 7) of unknown sex (≥ 228.6 cm) in the Academy of Natural Sciences of Drexel University (deposited under the museum number ANSP 3020), collected by S. B. Howell (collector). The specimen was obtained from a fisherman’s seine net at the Red Bank, a community in the West Deptford Township (NJ, USA), along the Delaware River, to the east of Philadelphia (PA, USA). Vertebral formula: C7 + T12 + L14 + Ca14+. Mitochondrial DNA control region haplotype (354 bp): Ttr2 (GenBank accession number: OM540927). Diagnosis: The skulls of T. erebennus can be differentiated from T. truncatus (offshore ecotype in the western North Atlantic) using the following five morphological features together. As observed from the left lateral view (Supporting Information, Fig. S1C): (1) cranial vertex elevated (anterior end of the nasals at slightly higher height than the other components of the cranial vertex); (2) shorter lacrimal, with its anterior end more flat (square shaped) and ending before the anterior end of the ascending process of the maxilla (usually, the latter is fully covering the anterior end of the lacrimal, which ends at almost the same height as the preorbital process of the frontal); and (3) straight (non-convex) pharyngeal crest. As observed from the ventral view (Supporting Information, Fig. S1D): (4) intermediate to narrower vomer when compared with the posterior process of the pterygoids; and (5) the posterior border of the pterygoid hamuli is more in an acute angle to the sagittal plane of the skull. Tursiops erebennus specimens can also be differentiated from T. truncatus specimens based on molecular genetic characters: one fixed difference was found in the mtDNA control region between the species (based on a fragment of 1630 A. P. B. COSTA ET AL. 311 bp and 249 mtDNA control region haplotype sequences). Redescription: This is a small species of bottlenose dolphin, with a known maximum total body length of 286 cm. When considering only physically mature animals based on the vertebral column (N = 13), we found a known minimum total adult body length of 232 cm and a mean of 256 cm for the species. It can be differentiated from T. truncatus based on skull morphometrics (Mead & Potter, 1995; Toledo, 2013; present study), vertebral column morphology (present study), several genetic markers (Hoelzel et al., 1998; Kingston & Rosel, 2004; Rosel et al., 2009; present study), body length (Mead & Potter, 1995; present study), distribution (Torres et al., 2003; Rosel et al., 2009; Waring et al., 2009; Hayes et al., 2017), parasite load (Mead & Potter, 1990), food habits (Mead & Potter, 1995), haematological profile (Duffield et al., 1983) and, possibly, colour pattern (Wells & Scott, 1999). Based on our data set, the condylobasal length in physically mature skulls ranges from 426 to 510 mm, but it is possible that a larger sample size might show individuals outside this range. Physically mature skulls have a relatively short (based on our data set: 226.38–278.74 mm) and narrow (based on our data set: 65.87–86.43 mm) rostrum and narrow internal nares (based on our data set: 56.11–72.77 mm). The vertebral formula, based on 21 individuals, is C7 + T 12 + L 14–15 + Ca 26–28 = 59–61. It is uncommon to find scars of Crassicauda sp. in the skulls. There are, on average, 23 or 24 alveoli/teeth in each of the tooth rows. There is sexual dimorphism in this lineage based on traditional morphometric analysis of the skulls (with males usually being larger than females based on the skull data set) but not detected with geometric morphometrics. Distribution: Tursiops erebennus is distributed continuously along the western North Atlantic coast from New York to the east coast of the Florida Peninsula, inhabiting nearshore coastal and estuarine waters (Rosel et al., 2009; Waring et al., 2009). The extent of the distribution of this species further offshore on the continental shelf of the wNA and in other areas, such as the Gulf of Mexico, Bahamas and the Caribbean, is unknown. However, to date ‘coastal’-form dolphins from the Caribbean Sea have not shared haplotypes with T. erebennus, with a potential exception for only one dolphin from the northern Bahamas. Instead, they are placed in a separate, well-supported clade in the mtDNA control region phylogeny, suggesting some degree of divergence from T. erebennus. Given this apparent genetic divergence between the wNA coastal and Gulf of Mexico and Caribbean coastal animals, we recommend, at this time, that the south-east coast of Florida should be considered the southern limit for the distribution of T. erebennus. Further investigation is needed to resolve the relationship between these two clades, which in turn will clarify the distribution of T. erebennus., Published as part of Costa, Ana P. B., Mcfee, Wayne, Wilcox, Lynsey A., Archer, Frederick I. & Rosel, Patricia E., 2022, The common bottlenose dolphin (Tursiops truncatus) ecotypes of the western North Atlantic revisited: an integrative taxonomic investigation supports the presence of distinct species, pp. 1608-1636 in Zoological Journal of the Linnean Society (Zool. J. Linn. Soc.) (Zool. J. Linn. Soc.) 196 (4) on pages 1629-1630, DOI: 10.1093/zoolinnean/zlac025, http://zenodo.org/record/7386885, {"references":["Cope ED. 1865. Second contribution to a history of the Delphinidae. Proceedings of the Academy of Natural Sciences of Philadelphia 17: 278 - 281.","True FW. 1884. Catalogue of the aquatic mammals. United States National Museum Bulletin 27: 623 - 644.","Mead JG, Potter CW. 1995. Recognizing two populations of the bottlenose dolphin (Tursiops truncatus) off the Atlantic coast of North America: morphologic and ecologic considerations. IBI Reports 5: 31 - 44.","Toledo GAC. 2013. Variacao geografica em cranios de golfinhos nariz-de-garrafa, Tursiops Gervais, 1855, no Atlantico Ocidental [Geographic variation in the skulls of bottlenose dolphins, Tursiops Gervais, 1855, in the western Atlantic]. Unpublished D. Phil. Thesis, Universidade Federal da Paraiba.","Hoelzel AR, Potter CW, Best PB. 1998. Genetic differentiation between parapatric ' nearshore' and ' offshore' populations of the bottlenose dolphin. Proceedings of the Royal Society B: Biological Sciences 265: 1177 - 1183.","Kingston SE, Rosel PE. 2004. Genetic differentiation among recently diverged delphinid taxa determined using AFLP markers. Journal of Heredity 95: 1 - 10.","Rosel PE, Hansen L, Hohn AA. 2009. Restricted dispersal in a continuously distributed marine species: common bottlenose dolphins Tursiops truncatus in coastal waters of the western North Atlantic. Molecular Ecology 18: 5030 - 5045.","Torres LG, Rosel PE, D'Agrosa C, Read AJ. 2003. Improving management of overlapping bottlenose dolphin ecotypes through spatial analysis and genetics. Marine Mammal Science 19: 502 - 514.","Waring GT, Josephson E, Fairfield-Walsh CP, MazeFoley K. 2009. US Atlantic and Gulf of Mexico marine mammal stock assessments - 2008. NOAA Technical Memorandum NMFS-NE 210. Available at: https: // repository. library. noaa. gov / view / noaa / 3630.","Hayes SA, Josephson E, Maze-Foley K, Rosel PE. 2017. US Atlantic and Gulf of Mexico marine mammal stock assessments - 2016. NOAA Technical Memorandum NMFS-NE 241. Available at: https: // repository. library. noaa. gov / view / noaa / 14864.","Mead JG, Potter CW. 1990. Natural history of bottlenose dolphins along the central Atlantic Coast of the United States. In: Leatherwood S, Reeves RR, eds. The bottlenose dolphin. San Diego: Academic Press, 165 - 195.","Duffield DA, Ridgway SH, Cornell LH. 1983. Hematology distinguishes coastal and offshore forms of dolphins (Tursiops). Canadian Journal of Zoology 61: 930 - 933.","Wells R, Scott MD. 1999. Bottlenose dolphin - Tursiops truncatus (Montagu, 1821). In: Ridgway SH, Harrison R, eds. Handbook of marine mammals, Vol. 6. San Diego: Academic Press, 137 - 182."]}

Lahille's Bottlenose Dolphin, a subspecies of the Common Bottlenose Dolphin (Tursiops truncatus), occurs in low numbers only in southern Brazil, Uruguay and Argentina. Lahille?s Bottlenose Dolphins are mainly resident to localized areas and restricted to coastal habitat resulting in a vulnerability to increasing pressures from human activities. Bycatch, pollution and prey depletion are the main known threats to the subspecies. There is evidence that the subspecies is declining in at least part of its range due to bycatch in fisheries and other unknown factors, although robust data on population dynamics is limited. Genetic variability of the subspecies is low at both nuclear and mtDNA markers. The abundance of Lahille's Bottlenose Dolphins has been estimated for most parts of the subspecies´ range. The sum of available abundance estimates suggests a maximum total population size of 600 individuals. With an estimated 60% of mature individuals (Taylor et al. 2007), the total number of mature individuals in the subspecies can be estimated at 360, well below the threshold to be listed as Vulnerable under criterion D1. Fil: Vermeulen, Els. No especifíca; Fil: Fruet, Pedro. No especifíca; Fil: Costa, Ana P. B.. No especifíca; Fil: Coscarella, Mariano Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina Fil: Laporta, Paula. No especifíca