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Hi all - I did not have time in January when I normally write these up, but thanks to Covid quarantine I managed to get some time last month and write up a comprehensive review on my blog of every single 2019 paper in marine mammal paleontology. Enjoy! https://coastalpaleo.blogspot.com/2020/05/2019-in-review-advances-in-marine.html

Greetings, fossil folks. After posting an ID question the other day, and getting all excellent responses, I figured I had done my single"drive-by" post, as I just don't have any other fossil material to share. Then I flashed on a fossil that has been residing in the same place, my mom's walkway, for what may amount to a mere 1/500,000 of its life, or approximately 50 years. My folks bought their house back in the early 1970's. I was 15 or 16 at the time. The hardscaping was done with a lot of flagstone. Exposed on the surface of one slab, was a tooth of some sort, with more than 1/2 of its enamel intact. I recently showed it to my girlfriend, who thought it was pretty cool, and wondered why nobody had liberated it from the flagstone. I guess nobody had ever really thought about it. Anyway, I'm curious as to what type of creature it may have been from. My GF was thinking shark, but I have always thought it must be something else, as it looks rather canine to me, and doesn't seem to have any serrations on the edges like shark's teeth I've seen. That said, the base does seem more shark-like. So, my friends, what is it? Many thanks in advance for your help. My apologies for not including a scale reference in the image, but the length is ~30mm and the width of the base is ~27mm. I hope that helps. BTW, if folks here think it's worth saving, please offer advice on what to do to preserve it. Cheers.

Anyone know what these various teeth are from? I think the big one is Allodesmus but the rest I'm not sure about. Collected over the last few years at Ernst Quarries in Bakersfield.

Hey Hi Folks, I Found this bone at Sharktooth hill this spring. It has been hiding in one of the buckets of matrix that I collected. Is it a Sea Lion femur? Is it possible to tell which critter it came from? Thanks for the help!! Tony More pictures coming...

These are a few of the pdf files (and a few Microsoft Word documents) that I've accumulated in my web browsing. MOST of these are hyperlinked to their source. If you want one that is not hyperlinked or if the link isn't working, e-mail me at joegallo1954@gmail.com and I'll be happy to send it to you. Please note that this list will be updated continuously as I find more available resources. All of these files are freely available on the Internet so there should be no copyright issues. Articles with author names in RED are new additions since May 23, 2018. Order Carnivora Clade Pinnipedia - Seals, Walruses and their Relatives Family undetermined Northover, J.M. (2010). Skeletal Morphology and Evidence for Swimming in a Fossil Stem Pinniped, Puijila darwini, from the Canadian High Arctic. Masters Thesis - Carleton University. Paterson, R. (2017). Evidence for independent acquisition of aquatic specializations in pinnipeds (seals, sea lions and walruses): insights from the study of the phylogenetic position, locomotor behaviour and description of the stem pinniped, Puijila darwini. Masters Thesis - Carleton University, Ottawa. (326 pages) Rybczynski, N., M.R. Dawson and R.H. Tedford (2009). A semi-aquatic Arctic mammalian carnivore from the Miocene epoch and origin of the Pinnipedia. Nature (Letters), Vol.458. Family Enliarctidae (†) Barnes, L.G. (1992). A New Genus and Species of Middle Miocene Enaliarctine Pinniped (Mammalia, Carnivora, Otariidae) from the Astoria Formation in Coastal Oregon.Contributions in Science, Natural History Museum of Los Angeles County, Number 431. Barnes, L.G.(1990). A New Miocene Enaliarctine Pinniped of the Genus Pteronarctos (Mammalia: Otariidae) from the Astoria Formation, Oregon.Contributions in Science, Natural History Museum of Los Angeles County, Number 422. Barnes, L.G. (1989). A New Enaliarctine Pinniped from the Astoria Formation, Oregon, and a Classification of the Otariidae (Mammalia: Carnivora). Contributions in Science, Natural History Museum of Los Angeles County, Number 403. Barnes, L.G. (1979). Fossil Enaliarctine Pinnipeds (Mammalia: Otariidae) from Pyramid Hill, Kern County, California. Contributions in Science, Natural History Museum of Los Angeles County, Number 318. Berta, A. (1994). New Specimens of the Pinnipediform Pteronarctos from the Miocene of Oregon. Smithsonian Contributions to Paleobiology, Number 78. Berta, A. (1991). New Enaliarctos* (Pinnipedimorpha) from the Oligocene and Miocene of Oregon and the Role of "Enaliarctids" in Pinniped Phylogeny. Smithsonian Contributions to Paleobiology, Number 69. Cullen, T. (2012). Comparative description of a female Enaliarctos emlongi (Carnivora, Pinnipedimorpha) from the mid-Miocene of Oregon and the evolution of sexual dimorphism within Pinnipedia. Masters Thesis - Carleton University, Ottawa. Cullen, T., et al. (2014). Early Evolution of Sexual Dimorphism and Polygyny in Pinnipedia. Evolution. Mitchell, E. and R.H. Tedford (1973). The Enliarctinae: A New Group of Extinct Aquatic Carnivora and a Consideration of the Origin of the Otariidae. Bulletin of the American Museum of Natural History, Vol.151, Article 3. Poust, A.W. and R.W. Boessenecker (2018). Expanding the geographic and geochronologic age of early pinnipeds: New specimens of Enaliarctos from Northern California and Oregon. Acta Palaeontologica Polonica, 63(1). Superfamily Otarioidea Family Odobenidae - Walruses Odobenidae - Asia/Malaysia/Pacific Islands Kohno, N. and Y. Hasegawa (1991). 921. A New Occurrence of Imagotariine Pinniped from the Middle Miocene Goudo Formation in Hagashimatsuyama City, Saitama, Japan. Trans.Proc.Paleont.Soc. Japan, N.S., Number 162. Takeyama, K.-i. and T. Ozawa (1984). A New Miocene Otarioid Seal from Japan. Proc. Japan Acad., Series B, Vol.60, Number 3. Tanaka, Y. and N. Kohno (2015). A New Late Miocene Odobenid (Mammalia: Carnivora) from Hokkaido, Japan Suggests Rapid Diversification of Basal Miocene Odobenids. PLoS ONE, 10(8). (Thanks to Boesse for pointing this one out!) Odobenidae - Europe (including Greenland and Siberia) Borissiak, A. (1930). A fossil walrus from the Okhotsk coast. Annals Russ.Paleontol.Soc., 8. Bosscha Erdbrink, D.P. and P.J.H. Van Bree (1999). Fossil Axial Skeletal Walrus Material from the North Sea and the Estuary of the Schelde, and a Fossil Sirenian Rib (Mammalia, Carnivora; Sirenia). Beaufortia, Vol.49, Number 2. Bosscha Erdbrink, D.P. and P.J.H. Van Bree (1986). Fossil Odobenidae in Some Dutch Collections. Beaufortia, Vol.36, Number 2. Rutten, L. (1907). On fossil Trichechids from Zealand and Belgium. KNAW, Proceedings, 10I. Van Der Feen, P.J. (1968). A Fossil Skull Fragment of a Walrus from the Mouth of the River Scheldt (Netherlands). Bijdragen tot de Dierkunde, Vol.38, Number 1. Odobenidae - North America Barnes, L.G. (1988). A New Fossil Pinniped (Mammalia: Otariidae) from the Middle Miocene Sharktooth Hill Bonebed, California. Contributions in Science, Natural History Museum of Los Angeles County, Number 396. Barnes, L.G. (1971). Imagotaria (Mammalia, Otariidae) from the Late Miocene Santa Margarita Formation near Santa Cruz, California. PaleoBios, Number 11. Barnes, L.G. and R.E. Raschke (1991). Gomphotaria pugnax, a New Genus and Species of Late Miocene Dusignathine Otariid Pinniped (Mammalia: Carnivora) from California. Contributions in Science, Natural History Musueum of Los Angeles County, Number 426. Boessenecker, R.W. (2017). A New Early Pliocene Record of the Toothless Walrus Valenictus (Carnivora, Odobenidae) from the Purisima Formation of Northern California. PaleoBios, 34. Boessenecker, S.J., R.W. Boessenecker and J.H. Geisler (2018). Youngest record of the extinct walrus Ontocetus emmonsi from the Early Pleistocene of South Carolina and a review of North Atlantic walrus biochronology. Acta Palaeontologica Polonica, 63(2). Bouchard, M.A., C.R. Harington and J.-P. Gilbault (1993). First evidence of walrus (Odobenus rosmarus L.) in Late Pleistocene Champlain Sea sediments, Quebec. Can.J. Earth Sci., 30. Deméré, T.A. (1994). Two New Species of Fossil Walruses (Pinnipedia: Odobenidae) from the Upper Pliocene San Diego Formation, California. In: Contributions in Marine Mammal Paleontology Honoring Frank C. Whitmore, Jr. Berta, A. and T.A. Deméré (eds.), Proc. San Diego Soc.Nat.Hist., 29. Deméré, T.A. and A. Berta (2001). A Reevaluation of Proneotherium repenningi from the Miocene Astoria Formation of Oregon and its Position as a Basal Odobenid (Pinnipedia: Mammalia). Journal of Vertebrate Paleontology, 21(2). ######, A.S., et al. (1999). The Late Wisconsinan and Holocene Record of Walrus (Odobenus rosmarus) from North America: A Review with New Data from Arctic and Atlantic Canada. Arctic, Vol.52, Number 2. Harington, C.R. and G. Beard (1992). The Qualicum walrus: a Late Pleistocene walrus (Odobenus rosmarus) skeleton from Vancouver Island, British Columbia, Canada. Ann.Zool.Fennici, 28. Harington, C.R., T.W. Anderson and C.G. Rodrigues (1993). Pleistocene Walrus (Odobenus rosmarus) from Forteau, Labrador. Geographie physique et Quaternaire, Vol.47, Number 1. Kellogg, R. (1921). A New Pinniped from the Upper Pliocene of California. Journal of Mammalogy, Vol..2, Number 4. Miller, R.F. (1997). New Records and AMS Radiocarbon Dates on Quaternary Walrus (Odobenus rosmarus) from New Brunswick. Géographie physique et Quaternaire, Vol.51, Number 1. Miller, R.F. (1990). New records of postglacial walrus and a review of Quaternary marine mammals in New Brunswick. Atlantic Geology, 26. Mitchell, E.D. (1961). A New Walrus from the Imperial Pliocene of Southern California: With Notes on Odobenid and Otariid Humeri. Los Angeles County Museum Contributions in Science, Number 44. Rhoads, S.N. (1898). Notes on the Fossil Walrus of Eastern North America. Proceedings of the Academy of Natural Sciences of Philadelphia, Vol.50. General Odobenidae Boessenecker, R.W. and M. Churchill (2013). A Reevaluation of the Morphology, Paleoecology, and Phylogenetic Relationships of the Enigmatic Walrus Pelagiarctos. PLoS ONE, Vol.8, Issue 1. (Thanks to Boesse for sharing this one!) Deméré, T.A. (1994). The Family Odobenidae: A Phylogenetic Analysis of Fossil and Living Taxa. In: Contributions in Marine Mammal Paleontology Honoring Frank C. Whitmore, Jr. Berta, A. and T.A. Demere (eds.). Proc. San Diego Soc.Nat.Hist., 99. Loch, C, et al. (2016). Enamel ultrastructure of fossil and modern pinnipeds: evaluating hypotheses of feeding adaptations in the extinct walrus Pelagiarctos. Sci.Nat., 103(5-6). Wyss, A.R. (1987). The Walrus Auditory Region and the Monophyly of Pinnipeds. American Museum Novitates, Number 2871. Family Otariidae - Fur Seals, Sea Lions and Their Relatives Boessenecker, R.W. and M. Churchill (2015). The oldest known fur seal. Biol.Lett., 11. Velez-Juarbe, J. (2017). Eotaria citrica, sp.nov., a new stem otariid from the "Topanga" formation of Southern California. PeerJ, 5:e3022. Subfamily Arctocephalinae - Fur Seals Beentjes, M.P. (1989). Evolutionary Ecology of the New Zealand Fur Seal (Arctocephalus forsteri) and hooker's Sea Lion (Phocarctos hookeri). Ph.D. Thesis - University of Otago. Berry, J.A. (1928). A New Species of Fossil Arctocephalus from Cape Kidnappers. Transactions of the New Zealand Institute, Vol.59. Berta, A. and T.A. Deméré (1986). Callorhinus gilmorei n.sp. (Carnivora: Otariidae) from the San Diego Formation (Blancan) and its implication for otariid phylogeny. Transactions of the San Diego Society of Natural History, Vol.21, Number 7. Subfamily Otariinae - Sea Lions Barnes, L.G., C.E. Ray and I.A. Koretsky (2005). A New Pliocene Sea Lion, Proterozetes ulysses (Mammalia: Otariidae) from Oregon, USA. In: Mesozoic and Cenozoic Vertebrates and Paleoenvironments. Tributes to the career of Prof. Dan Grigorescu. Csiki, Z. (ed.), Ars Docendi. Beentjes, M.P. (1989). Evolutionary Ecology of the New Zealand Fur Seal (Arctocephalus forsteri) and hooker's Sea Lion (Phocarctos hookeri). Ph.D. Thesis - University of Otago. Deméré, T.A. and A. Berta (2005). New Skeletal Material of Thalassoleon (Otariidae: Pinnipeda) from the Late Miocene-Early Pliocene (Hemphillian) of California. Bull. Fla. Mus. Nat. Hist. 45(4). Drehmer, C.J. and A.M. Ribeiro (1998). A Temporal Bone of an Otariidae (Mammalia, Pinnipedia) from the Late Pleistocene of Rio Grande do Sul State, Brazil. Revista universidade gualruhos Geociencias, III(6). Drehmer, C.J., M.E. Fabian and J.O. Menegheti (2004). Dental Anomalies in the Atlantic Population of South American Sea Lion, Otaria byronia (Pinnipedia, Otariidae): Evolutionary Implications and Ecological Approach. LAJAM, 3(1). Harington, C.R., et al. (2004). A late Pleistocene Steller Sea Lion (Eumetopias jubatus) from Courtenay, British Columbia: its death, associated biota and and paleoenvironment. Can.J. Earth Sci., 41. King, J.E. (1983). The Ohope Skull - a new species of Pleistocene sealion from New Zealand. New Zealand Journal of Marine and Freshwater Research, Vol.17. Nagao, T. (1941). An Occurrence of a Fossil Sea Lion in the Miocene Deposits of Sinano, Japan. Journ.Fac.Sci., Hokkaido Imp.Univ., Ser.IV, Vol.VI, Number 2. Worthy, T.H. (1992). Fossil Bones of hooker's Sea Lions in New Zealand Caves. New Zealand Natural Sciences, 19. General Otariidae Boessenecker, R.W. and F.A. Perry (2011). Mammalian Bite Marks on Juvenile Fur Seal Bones from the Late Neogene Purisima Formation of Central California. Palaios, Vol.26. Churchill, M., R.W. Boessenecker and M.T. Clementz (2014). Colonization of the Southern Hemisphere by fur seals and sea lions (Carnivora: Otariidae) revealed by combined evidence phylogenetic and Bayesian biogeographical analysis. Zoological Journal of the Linnean Society, 172. Sanfelice, D. and S.J. Drehmer (2013). Interpretation of anatomical characters in phylogenetic analysis of Pinnipedia, with emphasis on Otariidae (Mammalia, Carnivora). Biotemas, 26(2). General Otarioidea Repenning, C.A. and R.H. Tedford (1977). Otarioid Seals of the Neogene. United States Geological Survey, Professional Paper 992. Takeyama, K.-i. and T. Ozawa (1984). 10. A New Miocene Otarioid Seal from Japan. Proc. Japan Acad., Series B, Vol.60(B). Superfamily Phocoidea Family Desmatophocidae (†) Barnes, L.G. (1987). An Early Miocene Pinniped of the Genus Desmatophoca (Mammalia: Otariidae) from Washington. Contributions in Science, Natural History Museum of Los Angeles County, Number 382. Barnes, L.G. (1970). A re-evaluation of mandibles of Allodesmus (Otariidae, Carnivora) from the Round Mountain Silt, Kern County, California. PaleoBios, Number 10. Condon, T. (1906). A New Fossil Pinniped (Desmatophoca oregonensis) from the Miocene of the Oregon Coast. University of Oregon Bulletin, Supplement to Vol.III, Number 3. Deméré, T.A. and A. Berta. The Miocene Pinniped Desmatophoca oregonensis Condon, 1906 (Mammalia: Carnivora), from the Astoria Formation of Oregon. Smithsonian Contributions to Paleobiology, Number 93. Furbish, R. (2015). Something Old, Something New, Something Swimming in the Blue: An Analysis of the Pinniped Family Desmatophocidae, its Phylogenetic Position and Swimming Mode. Masters Thesis - San Diego State University. Kohno, N. (1996). 1007. Miocene pinniped Allodesmus (Mammalia: Carnivora); with special reference to the "Mito seal" from Ibaraki Prefecture, Central Japan. Trans.Proc.Paleont.Soc. Japan, N.S., Number 181. Nagao, T. (1941). An Occurrence of a Fossil Sea Lion in the Miocene Deposits of Sinano, Japan. Journal of the Faculty of Science, Hokkaido Imperial University, Series 4, Geology and mineralogy, 6(2). Family Phocidae - True Seals Subfamily Cystophorinae - Hooded Seals Koretsky, I.A. and S.J. Rahmat (2013). First Record of Fossil Cystophorinae (Carnivora, Phocidae): Middle Miocene Seals from the Northern Paratethys. Revista Italiana di Paleontologia e Stratigrafia, Vol.119, Number 3. Schneider, S. and K. Hessig (2005). An early seal (Mammalia, Pinnipedia) from the Middle Miocene (Langhian) of Miste (The Netherlands). Scripta Geol., 129. Subfamily Devinophocinae (†) Koretsky, I.A. and S.J. Rahmat (2015). A New Species of the Subfamily Devinophocinae (Carnivora, Phocidae) from the Central Paratethys. Revista Italiana di Paleontologia e Stratigrafia, Vol.121, Number 1. Rahmat, S.J. and I.A. Koretsky (2016). First Record of Postcranial Bones in Devinophoca emryi (Carnivora, Phocidae, Devinophocinae). Vestnik zoologii, 50(1). Subfamily Monachinae - Monk Seals, Elephant Seals and Their Relatives Amson, E. and C. de Muizon (2014). A new durophagous phocid (Mammalia: Carnivora) from the late Neogene of Peru and considerations on monachine seals phylogeny. Journal of Systematic Palaeontology, Vol.12, Issue 5. Berta, A., et al. (2015). A Reevaluation of Pliophoca etrusca (Pinnipedia, Phocidae) from the Pliocene of Italy: Phylogenetic and Biogeographic Implications. Journal of Vertebrate Paleontology, e889144. Dewaele, W., et al. (2018). Diversity of late Neogene Monachinae (Carnivora, Phocidae) from the North Atlantic, with the description of two new species. R.Soc. open sci., 5:172437. Koretsky, I.A. and D.P. Domning (2014). One of the Oldest Seals (Carnivora, Phocidae) from the Old World. Journal of Vertebrate Paleontology, 34(1). Koretsky, I.A. and D. Grigorescu (2002). The Fossil Monk Seal Pontophoca sarmatica (Alekseev) (Mammalia: Phocidae: Monachinae) from the Miocene of Eastern Europe. In: Cenozoic Mammals of Land and Sea: Tributes to the Career of Clayton E. Ray. Emry, R.J. (ed.), Smithsonian Institution Press, Washington, D.C. Rahmat, S.J., et al. (2017). New Miocene Monachine from the Western Shore of the Chesapeake Bay (Maryland, USA). Vestnik zoologii, 51(3). Valenzuela-Toro, A.M., et al. (2015). A New Dwarf Seal from the Late Neogene of South America and the Evolution of Pinnipeds in the Southern Hemisphere. Papers in Palaeontology. Valenzuela-Toro, A.M., et al. (2015). Elephant Seal (Mirounga sp.) from the Pleistocene of the Antofagasta Region, Northern Chile. Journal of Vertebrate Paleontology, e918883. Walsh, S. and D. Naish (2002). Fossil Seals from Late Neogene Deposits in South America: A New Pinniped (Carnivora, Mammalia) Assemblage from Chile. Palaeontology, Vol.45,Part 4. Subfamily Phocinae Antonyuk, A.A. and I.A. Koretskaya (1984). A New Species of Seal from the Sarmatian Deposit of the Crimea. Vestnik Zoologii, 4. Cozzuol, M.A. (2001). A "Northern" Seal from the Miocene of Argentina: Implications for Phocid Phylogeny and Biogeography. Journal of Vertebrate Paleontology, 21(3). Dewaele, L., O. Lambert and S. Louwye (2017). On Prophoca and Leptophoca (Pinnipedia, Phocidae) from the Miocene of the North Atlantic realm: redescription, phylogenetic affinities and paleobiogeographic implications. PeerJ, 5:e3024. Dewaele, L., et al. (2017). Reappraisal of the extinct seal "Phoca" vitulinoides from the Neogene of the North Sea Basin, with bearing on its geological age, phylogenetic affinities, and locomotion. PeerJ, 5:e3316. Koretsky, I.A. (2003). New finds of Sarmatian seals (Mammalia, Carnivora, Phocinae) from southern Hungary. Advances in Vertebrate Paleontology "Hen to Panta". Koretsky, I.A. (1987). The position of the genus Praepusa in the Phocinae system. Vestnik Zoologii. Koretsky, I.A. and N. Peters (2008). Batavipusa (Carnivora, Phocidae, Phocinae): a new genus from the eastern shore of the North Atlantic Ocean (Miocene Seals of the Netherlands, part II). DEINSEA, 12. Koretsky, I.A., N. Peters and S.J. Rahmat (2015). New Species of Praepusa (Carnivora, Phocidae, Phocinae) from The Netherlands Supports East to West Neogene Dispersal of True Seals. Vestnik zoologii, 49(1). Koretsky, I.A., C.E. Ray and N. Peters (2012). A new species of Leptophoca (Carnivora, Phocidae, Phocinae) from both sides of the North Atlantic Ocean (Miocene seals of the Netherlands, part I). DEINSEA, 15. Ray, C.E. (1976). Phoca wymani and Other Tertiary Seals (Mammalia: Phocidae) Described from the Eastern Seaboard of North America. Smithsonian Contributions to Paleobiology, Number 28. Wyss, A.R. (1988). On "Retrogression" in the Evolution of the Phocinae and Phylogenetic Affinities of the Monk Seals. American Museum Novitates, Number 2924. General Phocidae Diedrich, C. (2011). The world's oldest fossil seal record. Natural Science, Vol.3, Number 11. Fulton, T.L. and C. Strobeck (2010). Multiple fossil calibrations, nuclear loci and mitochondrial genomes provide new insight into biogeography and divergence timing for true seals (Phociidae, Pinnipedia). Journal of Biogeography, 37. Koretsky, I.A. and L.G. Barnes (2008). 32. Phocidae. In: Evolution of Tertiary Mammals in North America. Vol.2: Small Mammals, Xenarthrans and Marine Mammals. Janis, C.M., G.F. Gunnell and M.D. Uhen (eds.), Cambridge University Press. Koretsky, I.A. and C.E. Ray (2008). Phocidae of the Pliocene of Eastern USA. In: Geology and Paleontology of the Lee Creek Mine, North Carolina, IV. Ray, C.E., et al. (eds.), Virginia Museum of Natural History Special Publication, Number 14. Koretsky, I.A. and A.E. Sanders (2002). Paleontology of the Late Oligocene Ashley and Chandler Bridge Formations of South Carolina, 1: Paleogene Pinniped Remains; The Oldest Known Seal (Carnivora: Phocidae). Smithsonian Contributions to Paleobiology, Number 93. Koretsky, I.A., S.J. Rahmat and N. Peters (2014). Rare Late Miocene Seal Taxa (Carnivora, Phocidae) from the North Sea Basin. Vestnik zoologii, 48(5). McLaren, I.A. (1975). A Speculative Overview of Phocid Evolution. Rapp.P.-v.Reun.Cons.int.Explor.Mer., 169. Tarasenko, K.K., et al. (2015). The First Find of Fossil Seals (Phocidae, Carnivora, Mammalia) in the Maikop Beds of Kalmykia. Doklady Biological Sciences, Vol.465. True, F.W. (1906). Description of a New Genus and Species of Fossil Seal from the Miocene of Maryland. Proceedings of the United States National Museum, Vol.XXX, Number 1475. Van Bree, P.J.H. and D.P. Bosscha Erdbrink (1987). Fossil Phocidae in Some Dutch Collections. Beaufortia, Vol.37, Number 3. General Pinnipeds Arnason, U., et al. (2006). Pinniped phylogeny and a new hypothesis for their origin and dispersal. Molecular Phylogenetics and Evolution, 41. Berta, A. and M. Churchill (2012). Pinniped taxonomy: review of currently recognized species and subspecies, and evidence used for their description. Mammal Review, Vol.42, Number 3. Boessenecker, R.W. (2013). A new marine vertebrate assemblage from the Late Neogene Purisima Formation in Central California, part II: Pinnipeds and Cetaceans. Geodiversitas, 35(4). Cullen, T.M., et al. (2014). Early Evolution of Sexual Dimorphism and Polygyny in Pinnipedia. Evolution, 68(5). Jones, K.E. and A. Goswami (2009). Quantitative analysis of the influences of phylogeny and ecology on phocid and otariid pinniped (Mammalia; Carnivora) cranial morphology. Journal of Zoology, 280(3). Koretsky, I.A. and L.G. Barnes (2006). Pinniped Evolutionary History and Paleobiogeography. In: Mesozoic and Cenozoic Vertebrates and Paleoenvironments: Tributes to the career of Prof. Dan Grigorescu. Z. Csiki (ed.), Ars Docendi. Koretsky, I.A., L.G. Barnes and S.J. Rahmat (2016). Re-Evaluation of Morphological Characters Questions Current Views of Pinniped Evolution. Vestnik zoologii, 50(4). Mitchell, E.D. (1975). Parallelism and Convergence in the Evolution of Otariidae and Phocidae. P.-v. Reun.Cons.int.Explor.Mer., 169, Section 1: Evolution. Miyazaki, S., et al. (1994). Summary of the fossil record of pinnipeds of Japan, and comparisons with that from the eastern North Pacific. The Island Arc, 3. New Zealand Geological Survey Staff (1968). Notes from the New Zealand Geological Survey - 5. New Zealand Fossil Seals. New Zealand Journal of Geology and Geophysics, 11. Pierce, S.E., J.A. Clack and J.R. Hutchinson (2011). Comparative axial morphology in pinnipeds and its correlation with aquatic locomotory behavior. Journal of Anatomy, 219. Repenning, C.A. and R.H. Tedford (1977). Otarioid Seals of the Neogene. U.S. Geological Survey Professional Paper 992. Sanfelice, D. and S.J. Drehmer (2013). Interpretation of anatomical characters in phylogenetic analysis of Pinnipedia, with emphasis on Otariidae (Mammalia, Carnivora). Biotemas, 26(2). Valenzuela-Toro, A.M., et al. (2013). Pinniped Turnover in the South Pacific Ocean: New Evidence from the Plio-Pleistocene of the Atacama Desert, Chile. Journal of Vertebrate Paleontology, 33(1).

This is a sea lion skull I was lucky enough to find last Friday (June 7th) at the Ernst Quarry's in Bakersfield. It is from the round mountain silt of middle Miocene age. I am wondering what the species is, maybe it could be Alledesus or Neotherium but don't know how to tell. Any ideas are appreciated, thanks!