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Published: 2021-06-08

New species of latest Eocene/earliest Oligocene microgastropods (Heterobranchia: Orbitestellidae and Omalogyridae) from the Gries Ranch Formation, Lewis County, Washington State, USA

A.V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Palchevskogo Street 17, Vladivostok 690041, Russia.
Burke Museum of Natural History and Culture, University of Washington, Seattle, WA 98195, USA.
Mollusca Orbitestella Ammonicera Paleogene North Pacific SEM micromolluscs Crescent Formation


Continued sampling of the latest Eocene to earliest Oligocene Gries Ranch Formation in Lewis County, Washington State, has yielded new heterobranch microgastropod species. Orbitestella kieli sp. nov., is the third fossil species of this genus and family Orbitestellidae from western North America. Two new species of Ammonicera, A. rolani sp. nov. and A. danieli sp. nov., are together only the second fossil record of this genus and the family Omalogyridae from the northeastern Pacific Ocean. New specimens of two previously recorded species, O. palaiopacifica Squires & Goedert and A. benhami Squires & Goedert, from early Eocene rocks of the Crescent Formation provide new data regarding shell morphology. The fossil record of both Ammonicera and Orbitestella in western North America is restricted to early Eocene to earliest Oligocene age rocks in Washington State.



  1. Arnold, R. (1906) Geological reconnaissance of the coast of the Olympic Peninsula, Washington. Geological Society of America Bulletin, 17, 451–468.

    Babcock, R.S., Burmester, R.F., Engebretson, D.C. & Warnock, A. (1992) A rifted margin origin for the Crescent basalts and related rocks in the northern Coast Range volcanic province, Washington and British Columbia. Journal of Geophysical Research, 97, 6799–6821.

    Bartsch, P. (1907) New mollusks of the family Vitrinellidae from the West Coast of America. Proceedings of the United States National Museum, 32, 167–176.

    Beu, A.G. & Maxwell, P.A. (1990) Cenozoic Mollusca of New Zealand, drawings by R.C. Brazier. New Zealand Geological Survey Paleontological Bulletin, 58, 1–518, pls. 1–57.

    Buckeridge, J.S. (1997) Cirripedia: Thoracica. New ranges and species of Verrucomorpha from the Indian and Southwest Pacific Oceans. In: Crosnier, A. (Ed.), Résultats des Campagnes MUSORSTOM. Vol. 18. Mémoires du Muséum national d’Histoire naturelle, 176, pp. 125–149.

    Burmeister, H. (1837) Handbuch der Naturgeschichte. Vol. 2. Zoologie. Enslin, Berlin, pp. 369–858.

    Chernyshev, A.V. (2003) Three new species of the genus Ammonicera Vayssière, 1893 (Gastropoda, Omalogyridae) from the Japan Sea. Ruthenica, 13, 107–112.

    Cohen, K.M., Finney, S.C. & Gibbard, J.-X. (2013) The ICS International Chronostratigraphic Chart. Episodes, 36, 199–204. [updated, version 2020/03]

    Cossmann, M. (1888) Catalogue illustré des coquilles fossils de l’Éocène des environs de Paris. Fascicule 3. Annales de Société Royale Malacologique de Belgique, 23, 3–324, pls. 1–13.

    Dell’Angelo, B., Bonfitto, A. & Taviani, M. (2011) Chitons (Polyplacophora) from Paleogene strata in western Washington State, U.S.A. Journal of Paleontology, 85, 936–954.

    Dickerson, R.E. (1917) Climate and its influence upon the Oligocene faunas of the Pacific Coast, with descriptions of some new species from the Molopophorus lincolnensis Zone. Proceedings of the California Academy of Sciences, 7, 157–192, pls. 27–31.

    Durham, J.W. (1937) Gastropods of the Family Epitoniidae from Mesozoic and Cenozoic rocks of the West Coast of North America, including one new species by F. E. Turner and one by R. A. Bramkamp. Journal of Paleontology, 11, 479–512, pls. 56–57.

    Eddy, M.P., Clark, K.P. & Polenz, M. (2017) Age and volcanic stratigraphy of the Eocene Siletzia oceanic plateau in Washington and on Vancouver Island. Lithosphere, 9, 652–664.

    Effinger, W.L. (1938) The Gries Ranch fauna (Oligocene) of western Washington. Journal of Paleontology, 12, 355–390.

    Gatliff, J.H. (1906) On some Victorian marine Mollusca, new species and other little-known. Proceedings of the Royal Society of Victoria, New Series, 19, 1–4.

    Geiger, D.L. & Goedert, J.L. (2020) Scissurella nesbittae, new species, from the Gries Ranch Formation, Lewis County, Washington State (Gastropoda: Vetigastropoda: Scissurellidae). Zootaxa, 4759 (4), 593–596.

    Globerman, B.R., Beck, M.E. Jr. & Duncan, R.A. (1982) Paleomagnetism and tectonic significance of Eocene basalts from Black Hills, Washington Coast Range. Bulletin of the American Geological Society, 93, 1151–1159.;2

    Goedert, J.L. & Raines, B.K. (2016) First Paleogene Caecidae (Gastropoda: Truncatelloidea) from the northeastern Pacific Ocean and the earliest record for the genus Caecum Fleming, 1813. Proceedings of the Biological Society of Washington, 129, 38–47.

    Groves, L.T. (2011) New species of Paleogene cypraeoideans (Gastropoda) from the Pacific Slope of North America. The Nautilus, 125, 45–52.

    Groves, L.T. & Squires, R.L. (1995) First report of the genus Proadusta Sacco, 1894 (Gastropoda: Cypraeidae) from the Western Hemisphere, with a description of a new species from the Eocene of Washington. The Nautilus, 109, 113–116.

    Habe, T. (1972) The Japan’s smallest gastropod, Ammonicera japonica sp. nov. Venus, Japanese Journal of Malacology, 31, 115–116.

    Hickman, C.S. (1984) Composition, structure, ecology, and evolution of six Cenozoic deep-water mollusk communities. Journal of Paleontology, 58, 1215–1234.

    Hybertsen, F. & Kiel, S. (2018) A middle Eocene seep deposit with silicified fauna from the Humptulips Formation in western Washington State, USA. Acta Palaeontologica Polonica, 63, 751–768.

    Iredale, T. (1917) More molluscan name-changes, generic and specific. Proceedings of the Malacological Society of London, 12, 322–330.

    Landau, B.M., Ceulemans, L. & Van Dingenen, F. (2020) The upper Miocene gastropods of northwestern France, 6. Heterobranchia. Cainozoic Research, 20, 257–278.

    Lindberg, D.R. (1987) Recent and fossil species of the genus Erginus from the North Pacific Ocean (Patellogastropoda: Mollusca). PaleoBios, 12, 1–8.

    McLean, J.H. (1978) Marine shells of southern California, revised edition. Natural History Museum of Los Angeles County, Science Series, 24, 1–104, figs. 1–54.

    Monterosato, T. di M.A. (1869) Description de’espèces nouvelles de la Méditerranée. Journal de Conchyliologie, 17, 274–277, pl. 13.

    Myers, B.W. (1979) An historical review of the systematics of Orbitestella diegensis (Bartsch, 1907). The Festivus, 11, 64–66.

    Oliver, J.D. & Rolán, E. (2015) The genus Ammonicera (Heterobranchia, Omalogyridae) in the eastern Atlantic. 1: the species of the Iberian Peninsula. Iberus, 33, 45–95.

    Pease, M.H. Jr. & Hoover, L. (1957) Geology of the Doty-Minot Peak area, Washington. U.S. Geological Survey Oil and Gas Investigations Map, OM-188. [map]

    Perreault, R.T. & Buckeridge, J.S. (2019) Paleogene Verrucidae (Cirripedia: Verrucomorpha) of North America, with descriptions of three new species. Zootaxa, 4712 (1), 34–50.

    Ponder, W.F. (1990) The anatomy and relationships of the Orbitestellidae (Gastropoda: Heterobranchia). Journal of Molluscan Studies, 56, 515–532.

    Prothero, D.R. & Burns, C. (2001) Paleomagnetism of the upper Eocene Gries Ranch Formation, Grays Harbor [sic] County, Washington. In: Prothero, D.R. (Ed.), Magnetic Stratigraphy of the Pacific Coast Cenozoic. Society for Sedimentary Geology (SEPM) Book 91. Society for Sedimentary Geology, Tulsa, Oklahoma, pp. 179–183.

    Rau, W.W. (1966) Stratigraphy and Foraminifera of the Satsop River area, southern Olympic Peninsula, Washington. State of Washington Division of Mines and Geology Bulletin, 53, 1–66.

    Reid, D.G. (1996) Systematics and evolution of Littorina. The Ray Society, Publication, 164, 1–463.

    Roberts, A.E. (1958) Geology and coal resources of the Toledo-Castle Rock district, Cowlitz and Lewis counties, Washington. U.S. Geological Survey Bulletin, 1062, 1–71.

    Sars, G.O. (1878) Bidrag til kundskaben om Norges arktiske fauna. I. Mollusca regionis Arcticæ Norvegiæ. Oversigt over de I Norges arktiske region forekommende Bløddyr. A.W. Brøgger, Christiania, xvi + 466 pp. [1 map, 34 pls.]

    Sartori, A.F. & Bieler, R. (2014) Three new species of Ammonicera from the eastern Pacific coast of North America, with redescriptions and comments on other species of Omalogyridae (Gastropoda, Heterobranchia). Zootaxa, 3872 (1), 1–21.

    Sleurs, W. (1985) The marine microgastropods from the northern coast of Papua New Guinea (Mollusca: Gastropoda). I. Family: Omalogyridae (with descriptions of two new species) (1). Bulletin de l´Institut royal des Sciences naturelles de Belgique, 55, 1–11, 1 pl. [volume marked “31–XII–1983”, but published 8 March 1985]

    Squires, R.L. & Goedert, J.L. (1994) New species of early Eocene small to minute mollusks from the Crescent Formation, Black Hills, southwestern Washington. The Veliger, 37, 253–266.

    Squires, R.L. & Goedert, J.L. (1995) New species of middle Eocene gastropods from the northern Doty Hills, southwestern Washington. The Veliger, 38, 254–269.

    Squires, R.L. & Goedert, J.L. (1996) New species of small to minute gastropods of early Eocene age from the Crescent Formation, Black Hills, southwest Washington. The Veliger, 39, 226–240.

    Squires, R.L., Goedert, J.L., Benham, S.R. & Groves, L.T. (1996) Protoconch of the rare ovulid gastropod Cypraeogemmula warnerae Effinger, 1938, from the Eocene of western Washington. The Veliger, 39, 136–141.

    Tabor, R.W. & Cady, W.M. (1978) Geologic map of the Olympic Peninsula, Washington. U.S. Geological Survey Miscellaneous Investigations Series Map, I-994. [map]

    Tegland, N.M. (1931) The gastropod genus Galeodea in the Oligocene of Washington. University of California Publications, Bulletin of the Department of Geological Sciences, 19, 397–434, pls. 59–65.

    Van Winkle, K. (1918) Paleontology of the Oligocene of the Chehalis Valley, Washington. University of Washington, Publication in Geology, 1, 69–97.

    Vayssière, A.J.-B.M. (1893) Observations zoologiques & anatomiques sur l’Ammonicera, nouveau genre de gastéropode prosobranche. Annales de la Faculté des Sciences de Marseille, 3, 15–28, figs. 8–17.

    Waki, T., Lee, H.-J., Park, S.-R., Park, J., Kwun, H.-J. & Choi, K.-S. (2016) First report of the microgastropod Ammonicera japonica (Omalogyridae Habe 1972) in Korea. Journal of Asia-Pacific Biodiversity, 9, 180–182.

    Waki, T., Rolán, E., Noseworthy, R.G., Kang, H.-S. & Choi, K.-S. (2017) A new species of the genus Ammonicera (Prosobranchia, Omalogyridae) in a coralline algae community from Jeju Island, off the south coast of Korea. Ocean Science Journal, 52, 587–591.

    Weaver, C.E. (1937) Tertiary stratigraphy of western Washington and northwestern Oregon. University of Washington Publications in Geology, 4, 1–266.

    Weaver, C.E. (1943) Paleontology of the marine Tertiary formations of Oregon and Washington. University of Washington Publications in Geology, 5, 1–789.

    Yamaguchi, T. & Goedert, J.L. (2009) Early Eocene ostracodes from the Crescent Formation in southwestern Washington, USA. Journal of Micropalaeontology, 28, 1–14.