{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T18:45:47Z","timestamp":1776105947887,"version":"3.50.1"},"reference-count":1,"publisher":"Magnolia Press","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Zootaxa"],"abstract":"<jats:p>The American Alligator (Alligator mississippiensis) is one of two species of Alligator in the modern world. It is only distantly related to the other extant species (A. sinensis), with much closer relatives known from the geologic past of North America. A disparity exists, though, in the fossil record between A. mississippiensis and its close relative, the late Miocene (?)\u2014early Pliocene A. mefferdi. While A. mississippiensis is known from the mid-Pleistocene and later, few Alligator remains were known from the earliest Pleistocene of North America until the discovery of the Haile 7C and 7G early Pleistocene (Blancan Land Mammal Age) sites from Alachua County, Florida. The Haile alligators exhibit a suite of characters from both A. mississippiensis and A. mefferdi, displaying intermediate morphology in time. The Haile alligators are distinct from either of the aforementioned taxa, and a new species, Alligator hailensis is suggested, bridging an important gap in the evolution of the American Alligator.\u00a0<\/jats:p>","DOI":"10.11646\/zootaxa.4868.1.3","type":"journal-article","created":{"date-parts":[[2020,10,23]],"date-time":"2020-10-23T00:37:27Z","timestamp":1603413447000},"source":"Crossref","is-referenced-by-count":4,"title":["New early Pleistocene Alligator (Eusuchia: Crocodylia) from Florida bridges a gap in Alligator evolution"],"prefix":"10.11646","volume":"4868","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8747-3561","authenticated-orcid":false,"given":"JEREMY B.","family":"STOUT","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"4913","published-online":{"date-parts":[[2020,10,23]]},"reference":[{"key":"49840","unstructured":"<p class=\"Reference\">Borges, V.S., Santiato, P.C., Lima, N.G.S., Coutinho, M.E., Eterovik, P.C. &amp; Carvalho, D.C. (2018) Evolutionary significant units within populations of Neotropical broad-snouted caimans (<em>Caiman latirostris<\/em>, Daudin, 1802). <em>Journal of Herpetology<\/em>, 52 (3), 282\u2013288.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1670\/17-074\">https:\/\/doi.org\/10.1670\/17-074<\/a><\/p><p class=\"Reference\">Brochu, C.A. (1999) Cranial morphology of <em>Alligator mississippiensis<\/em> and phylogeny of Alligatoroidea. <em>Journal of Vertebrate Paleontology<\/em>, 19 (Memoir 6), 100 pp. <\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1080\/02724634.1999.10011201\">https:\/\/doi.org\/10.1080\/02724634.1999.10011201<\/a><\/p><p class=\"Reference\">Brochu, C.A. (2000) Phylogenetic relationships and divergence timing of <em>Crocodylus<\/em> based on morphology and the fossil record. <em>Copeia<\/em>, 2000 (3), 657\u2013673.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1643\/0045-8511(2000)000%5b0657:PRADTO%5d2.0.CO;2\">https:\/\/doi.org\/10.1643\/0045-8511(2000)000[0657:PRADTO]2.0.CO;2<\/a><\/p><p class=\"Reference\">Brochu, C. A. (2004) Alligatorine phylogeny and the status of <em>Allognathosuchus <\/em>Mook, 1921. <em>Journal of Vertebrate Paleontology<\/em>, 24 (4), 857\u2013873.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1671\/0272-4634(2004)024%5b0857:APATSO%5d2.0.CO;2\">https:\/\/doi.org\/10.1671\/0272-4634(2004)024[0857:APATSO]2.0.CO;2<\/a><\/p><p class=\"Reference\">Brochu, C.A. (2011) Phylogenetic relationships of <em>Necrosuchus ionensis<\/em> Simpson, 1937 and the early history of caimanines. <em>Zoological Journal of the Linnean Society<\/em>, 163 (supplement 1), S228\u2013S256.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1111\/j.1096-3642.2011.00716.x\">https:\/\/doi.org\/10.1111\/j.1096-3642.2011.00716.x<\/a><\/p><p class=\"Reference\">Brochu, C.A. &amp; Sumrall, C.D. (2020) Modern cryptic species and crocodylian diversity in the fossil record. <em>Zoological Journal of the Linnean Society<\/em>, 189 (2), 700\u2013711.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1093\/zoolinnean\/zlaa039\">https:\/\/doi.org\/10.1093\/zoolinnean\/zlaa039<\/a><\/p><p class=\"Reference\">Cossette, A.P. &amp; Brochu, C.A. (2018) A new specimen of the alligatoroid <em>Bottosaurus harlani<\/em> and the early history of character evolution in the alligatorids. <em>Journal of Vertebrate Paleontology<\/em>, 38 (4), 1\u201322.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1080\/02724634.2018.1486321\">https:\/\/doi.org\/10.1080\/02724634.2018.1486321<\/a><\/p><p class=\"Reference\">Cuvier, F. (1807) Sur les diff\u00e8rentes esp\u00e8ces de Crocodiles vivans et Sur leurs caract\u00e8res distinctiss. <em>Nouveau Bulletin des Sciences<\/em>, 1, 10\u201314. [in French]<\/p><p class=\"Reference\">Daudin, F.M. (1801) <em>Histoire naturelle, g\u00e9n\u00e9rale et particuli\u00e8re des reptiles: ouvrage faisant suite \u00e0 l\u2019histoire naturelle g\u00e9n\u00e9rale et particulie\u00e8re, compos\u00e9e par Leclerc de Buffon, et r\u00e9dig\u00e9e par CS Sonnini, membre de plusieurs soci\u00e9t\u00e9s savants<\/em> <em>Vol. 3<\/em>. Dufart, Paris, 384 pp. [in French]<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.5962\/bhl.title.60678\">https:\/\/doi.org\/10.5962\/bhl.title.60678<\/a><\/p><p class=\"Reference\">Eaton, M.J., Martin, A., Thorbjarnarson, J. &amp; Amato, G. (2009) Species-level diversification of African dwarf crocodiles (genus <em>Osteolaemus<\/em>): a geographic and phylogenetic perspective. <em>Molecular Phylogenetics and Evolution<\/em>, 50 (3), 496\u2013506.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1016\/j.ympev.2008.11.009\">https:\/\/doi.org\/10.1016\/j.ympev.2008.11.009<\/a><\/p><p class=\"Reference\">Fauvel, A.A. (1879) Alligators in China. <em>Journal of the North-China Branch of the Royal Asiatic Society Shanghai<\/em>, 13, 1\u201336.<\/p><p class=\"Reference\">Gray, J.E. (1844) <em>Catalogue of the Tortoises, Crocodiles, and Amphisbaenians, in the Collection of the British Museum<\/em>. Order of the Trustees, London, 80 pp.<\/p><p class=\"Reference\">Hekkala, E., Shirley, M.H., Amato, G., Austin, J.D., Charter, S., Thorbjarnarson, J., Vliet, K.A., Houck, M.L., DeSalle, R. &amp; Blum, M.J. (2011) An ancient icon reveals new mysteries: mummy DNA resurrects a cryptic species within the Nile crocodile. <em>Molecular Ecology<\/em>, 20 (20), 4199\u20134215.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1111\/j.1365-294X.2011.05245.x\">https:\/\/doi.org\/10.1111\/j.1365-294X.2011.05245.x<\/a><\/p><p class=\"Reference\">Holman, J.A. (1972) Herpetofauna of the Calf Creek local fauna (lower Oligocene: Cypress Hills Formation) of Saskatchewan. <em>Canadian Journal of Earth Sciences<\/em>, 9 (12), 1612\u20131631.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1139\/e72-143\">https:\/\/doi.org\/10.1139\/e72-143<\/a><\/p><p class=\"Reference\">Holman, J.A (1995) <em>Pleistocene Amphibians and Reptiles in North America<\/em>. Oxford University Press, New York, 243 pp.<\/p><p class=\"Reference\">Hulbert Jr., R.C. (1997) A new late Pliocene porcupine (Rodentia: Erethizontidae) from Florida. <em>Journal of Vertebrate Paleontology<\/em>, 17 (3), 623\u2013626.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1080\/02724634.1997.10011010\">https:\/\/doi.org\/10.1080\/02724634.1997.10011010<\/a><\/p><p class=\"Reference\">Hulbert Jr., R.C. (2001) <em>The Fossil Vertebrates of Florida<\/em>. University of Florida Press, Gainesville, 384 pp.<\/p><p class=\"Reference\">Hulbert Jr., R.C. (2010) A new early Pleistocene tapir (Mammalia: Perissodactyla) from Florida, with a review of Blancan tapirs from the state. <em>Bulletin of the Florida Museum of Natural History<\/em>, 49 (3), 67\u2013126.<\/p><p class=\"Reference\">Hulbert Jr., R.C., Bloch, J. &amp; Poyer, A. (2006) Exceptional preservation of vertebrates from Haile 7G, a new late Pliocene site from Florida. <em>Journal of Vertebrate Paleontology<\/em>, 26 (supplement to Number 3), 78A\u201379A.<\/p><p class=\"Reference\">Hulbert Jr., R.C. &amp; Morgan, G.S. (2009) Two new late Blancan vertebrate sites from Florida, with a reassessment of late Pliocene vertebrate biochronology in Florida. Southeastern Association of Vertebrate Paleontology, 2nd Annual Meeting, Martinsville, Virginia.<\/p><p class=\"Reference\">Huxley, T.H. (1875) On <em>Stagonolepis robertsoni<\/em> and on the evolution of the Crocodylia. <em>Quarterly Journal of the Geological Society of London<\/em>, 31, 423\u2013438.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1144\/GSL.JGS.1875.031.01-04.29\">https:\/\/doi.org\/10.1144\/GSL.JGS.1875.031.01-04.29<\/a><\/p><p class=\"Reference\">Iijima, M., Takahashi, K. &amp; Kobayashi, Y. (2016) The oldest record of <em>Alligator sinensis <\/em>from the Late Pliocene of Western Japan, and its biogeographic implication. <em>Journal of Asian Earth Sciences<\/em>, 124, 94\u2013101.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1016\/j.jseaes.2016.04.017\">https:\/\/doi.org\/10.1016\/j.jseaes.2016.04.017<\/a><\/p><p class=\"Reference\">Li, J.L. &amp; Wang, B.Z. (1987) A new species of <em>Alligator<\/em> from Shanwang, Shandong. <em>Vertebrata PalAsiatica<\/em>, 25 (3), 199\u2013207.<\/p><p class=\"Reference\">Malone, B. (1979) <em>The Systematics, Phylogeny and Paleobiology of the Genus<\/em> Alligator. City University of New York (PhD dissertation), New York, 159 pp. <\/p><p class=\"Reference\">May, S.R. (2019) The Lapara Creek Fauna: Early Clarendonian of south Texas, USA. <em>Palaeontologia Electronica<\/em>, 22 (1), 130 pp.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.26879\/929\">https:\/\/doi.org\/10.26879\/929<\/a><\/p><p class=\"Reference\">Mook, C.C. (1923) A new species of Alligator from the Snake Creek beds. <em>American Museum Novitates<\/em>, 73, 1\u201313.<\/p><p class=\"Reference\">Mook, C.C. (1932) A study of the osteology of <em>Alligator prenasalis<\/em> (Loomis). <em>Bulletin of the Museum of Comparative Zoology at Harvard College<\/em>, 74, 19\u201341.<\/p><p class=\"Reference\">Mook, C.C. (1946) A new Pliocene alligator from Nebraska. <em>American Museum Novitates<\/em>, 1311, 285\u2013304. <\/p><p class=\"Reference\">Morgan, G.S. &amp; Hulbert Jr., R.C. (1995) Overview of the geology and vertebrate biochronology of the Leisey Shell Pit local fauna, Hillsborough County, Florida. <em>Bulletin of the Florida Museum of Natural History<\/em>, 37, 1\u201392.<\/p><p class=\"Reference\">Murray, C.M., Russo, P., Zorrilla, A. &amp; McMahan, C.D. (2019) Divergent morphology among populations of the New Guinea crocodile, <em>Crocodylus novaeguineae<\/em> (Schmidt, 1928): diagnosis of an independent lineage and description of a new species. <em>Copeia<\/em>,<em> <\/em>107 (3), 517\u2013523.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1643\/CG-19-240\">https:\/\/doi.org\/10.1643\/CG-19-240<\/a><\/p><p class=\"Reference\">Oaks, J.R. (2011) A time-calibrated species tree of Crocodylia reveals a recent radiation of the true crocodiles. <em>Evolution<\/em>,<em> <\/em>65 (11), 3285\u20133297.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1111\/j.1558-5646.2011.01373.x\">https:\/\/doi.org\/10.1111\/j.1558-5646.2011.01373.x<\/a><\/p><p class=\"Reference\">Schmidt, K.P. (1941) A new fossil alligator from Nebraska. <em>Fieldiana: Geology<\/em>,<em> <\/em>8, 27\u201332.<\/p><p class=\"Reference\">Schubert, B., Mead, J. &amp; Stout, J. (2011) Late Neogene <em>Alligator<\/em> evolution and a description of specimens from the Gray Fossil Site, Southern Appalachians, USA. <em>Journal of Vertebrate Paleontology<\/em>, 31 (Supplement 2), 189.<\/p><p class=\"Reference\">Shan, H-C., Cheng, Y-N. &amp; Wu, X-C. (2013) The first fossil skull of <em>Alligator sinensis<\/em> from the Pleistocene, Taiwan, with a paleogeographic implication of the species. <em>Journal of Asian Earth Sciences<\/em>, 69, 17\u201325.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1016\/j.jseaes.2012.05.026\">https:\/\/doi.org\/10.1016\/j.jseaes.2012.05.026<\/a><\/p><p class=\"Reference\">Snyder, D. (2007) Morphology and systematics of two Miocene alligators from Florida, with a discussion of <em>Alligator<\/em> biogeography. <em>Journal of Paleontology<\/em>, 81 (5), 917\u00ad\u2013928. <\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1666\/pleo05-104.1\">https:\/\/doi.org\/10.1666\/pleo05-104.1<\/a><\/p><p class=\"Reference\">Swofford, D.L. (2001) <em>PAUP*: Phylogenetic Analysis Using Parsimony (*and other methods)<\/em>. Sinauer Associates, Sunderland, Massachusetts.<\/p><p class=\"Reference\">Taplin, L.E. &amp; Grigg, G.C. (1989) Historical zoogeography of the eusuchian crocodilians: a physiological perspective. <em>American Zoologist<\/em>, 29 (3), 885\u2013901.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1093\/icb\/29.3.885\">https:\/\/doi.org\/10.1093\/icb\/29.3.885<\/a><\/p><p class=\"Reference\">Thorbjarnarson, J. &amp; Wang, X. (2010) <em>The Chinese Alligator: Ecology, Behavior, Conservation, and Culture<\/em>. Johns Hopkins University Press, Baltimore, 265 pp.<\/p><p class=\"Reference\">White, T.E. (1942) A new alligator from the Miocene of Florida. <em>Copeia<\/em>, 1942 (1), 3\u20137. <\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.2307\/1437933\">https:\/\/doi.org\/10.2307\/1437933<\/a><\/p><p class=\"Reference\">Whiting, E.T. &amp; Hastings, A.K. (2015) First fossil <em>Alligator <\/em>from the late Eocene of Nebraska and the late Paleogene record of alligators in the Great Plains. <em>Journal of Herpetology<\/em>, 49 (4), 560\u2013569.<\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1670\/14-069\">https:\/\/doi.org\/10.1670\/14-069<\/a><\/p><p class=\"Reference\">Whiting, E.T., Steadman, D.W. &amp; Vliet, K.A. (2016) Cranial polymorphism and systematics of Miocene and living <em>Alligator<\/em> in North America. <em>Journal of Herpetology<\/em>, 50 (2), 206\u2013215. <\/p><p class=\"Reference\"> <a href=\"https:\/\/doi.org\/10.1670\/15-023\">https:\/\/doi.org\/10.1670\/15-023<\/a><\/p><p>Wu, X-C., Brinkman, D.B. &amp; Russell, A.P. (1996) A new alligator from the Upper Cretaceous of Canada and the relationships of early eusuchians. <em>Palaeontology<\/em>, 39 (2), 351\u2013375.<\/p>"}],"container-title":["Zootaxa"],"original-title":[],"link":[{"URL":"https:\/\/www.mapress.com\/zt\/article\/download\/zootaxa.4868.1.3\/41620","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.mapress.com\/zt\/article\/download\/zootaxa.4868.1.3\/41620","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,2,21]],"date-time":"2023-02-21T23:03:16Z","timestamp":1677020596000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mapress.com\/zt\/article\/view\/zootaxa.4868.1.3"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,10,23]]},"references-count":1,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2020,10,23]]}},"URL":"https:\/\/doi.org\/10.11646\/zootaxa.4868.1.3","relation":{},"ISSN":["1175-5334","1175-5326"],"issn-type":[{"value":"1175-5334","type":"electronic"},{"value":"1175-5326","type":"print"}],"subject":[],"published":{"date-parts":[[2020,10,23]]}}}