Abstract
The pliomerid trilobite genus Hintzeia Harrington, 1957, includes only species from the early Tulean (upper Tremadocian) of the Great Basin, USA, and from the Northwest Territories, Canada. Previously assigned species reported from Scandinavia, China, South Korea, and Australia do not appear to be closely related to the western Laurentian species and are excluded from the genus. The monophyly of the group needs to be tested in the context of a broader phylogenetic analysis, but Hintzeia is rediagnosed with potential synapomorphies including a long, wide anterior border with a large, semicircular median arcuate anterior curve in the posterior margin. Hintzeia celsaora (Ross, 1951) and H. firmimarginis (Hintze, 1953) are redescribed based on large new collections from Utah and Idaho. Ontogenetic material of H. celsaora includes an articulated silicified M13 meraspid. Hintzeia parafirmimarginis n. sp. is described on the basis of both abundant disarticulated sclerites and a large articulated individual. Large topotype collections indicate that Hintzeia celsaora (Ross, 1951) is a senior synonym of Protopliomerops aemulus Hintze, 1953; previously claimed differences appear to reflect small original sample sizes, ontogenetic change, and differing photographic orientation.References
Adrain, J.M., McAdams, N.E.B. & Westrop, S.R. (2009) Trilobite biostratigraphy and revised bases of the Tulean and Blackhillsian Stages of the Ibexian Series, Lower Ordovician, western United States. Memoirs of the Association of Australasian Palaeontologists, 37, 541–610.
Adrain, J.M. & Westrop, S.R. (2007a) Bearriverops, a new Lower Ordovician trilobite genus from the Great Basin, western USA, and classification of the family Dimeropygidae. Canadian Journal of Earth Sciences, 44, 337–366.
Adrain, J.M. & Westrop, S.R. (2007b) The hystricurid trilobite Metabowmania in the Lower Ordovician (Ibexian; Stairsian) of the Great Basin, Utah and Idaho, USA. Memoirs of the Association of Australasian Palaeontologists, 34, 227–242.
Angelin, N.P. (1854) Palaeontologia Scandinavica. Pars II, Crustacea formationis transitionis. Academiae Regiae Scientarum Suecanae (Holmiae), pp. 25–92.
Angelin, N.P. (1878) Palaeontologia Scandinavica. Pars 1. Crustacea formationis transitionis. Fasciculi 1 & 2. Cum tabulis 48. Academiae Regiae Scientarum Suecanae (Holmiae), pp. 1–92.
Billings, E. (1859) Fossils of the Calciferous Sandrock, including those of a deposit of white limestone at Mingan, supposed to belong to the formation. Canadian Naturalist and Geologist, 4, 345–367.
Billings, E. (1865) Palaeozoic fossils. Vol I (4). Geological Survey of Canada, Montreal, 169–344.
Dalman, J.W. (1824) Några petrificater, fundne i Östergötlands Öfvergångskalk, aftecknade och beskrifne. Kungliga Svenska Vetenskapsakademiens Handlingar, 368–377. pl. 4.
Dean, W.T. (1989) Trilobites from the Survey Peak, Outram and Skoki formations (Upper Cambrian-Lower Ordovician) at Wilcox Pass, Jasper National Park, Alberta. Geological Survey of Canada Bulletin, 389, 1–141.
Demeter, E.J. (1973) Lower Ordovician pliomerid trilobites from western Utah. Brigham Young University Geology Studies, 20, 37–65.
Edgecombe, G.D. & Chatterton, B.D.E. (1987) Heterochrony in the Silurian radiation of encrinurine trilobites. Lethaia, 20, 337–351.
Fortey, R.A. (1980) The Ordovician trilobites of Spitsbergen. III. Remaining trilobites of the Valhallfonna Formation. Norsk Polarinstitutt Skrifter, 171, 1–163.
Harrington, H.J. (1957) Notes on new genera of Pliomeridae (Trilobita). Journal of Paleontology, 31, 811–812.
Harrington, H.J. & Leanza, A.F. (1957) Ordovician trilobites of Argentina. Special Publications, Department of Geology, University of Kansas, Lawrence, Kansas, 276 pp.
Hintze, L.F. (1951) Lower Ordovician detailed stratigraphic sections for western Utah. Utah Geological and Mineralogical Survey Bulletin, 39, 1–99.
Hintze, L.F. (1953) Lower Ordovician trilobites from western Utah and eastern Nevada. Utah Geological and Mineralogical Survey Bulletin, 48, 1–249. (for 1952)
Hintze, L.F. (1973) Lower and Middle Ordovician stratigraphic sections in the Ibex area, Millard County, Utah. Brigham Young University Geology Studies, 20, 3–36.
Hintze, L.F. & Davis, F.D. (2003) Geology of Millard County, Utah. Utah Geological Survey Bulletin, 133, 1–305.
Hoel, O.A. (1999) Trilobites of the Hagastrand Member (Tøyen Formation, lowermost Arenig) from the Oslo Region, Norway. Part II: Remaining non-asaphid groups. Norsk Geologisk Tidsskrift, 79, 259–280.
Holliday, S. (1942) Ordovician trilobites from Nevada. Journal of Paleontology, 16, 471–478.
Hupé, P. (1953) Classe des Trilobites. In: Piveteau, J. (Ed.), Trait de Paléontologie. Tome 3. Les Formes Ultimes d’Invertébrés. Morphologie et Évolution. Onycophores. Arthropodes. Échinoderms. Stomocordés. Masson et Cie, Paris, pp. 44–246.
Ingham, J.K., Curry, G.B. & Williams, A. (1986) Early Ordovician Dounans Limestone fauna, Highland Border Complex, Scotland. Transactions of the Royal Society of Edinburgh: Earth Sciences, 76, 481–513. (for 1985)
Jell, P.A. & Adrain, J.M. (2003) Available generic names for trilobites. Memoirs of the Queensland Museum, 48, 331–553.
Kobayashi, T. (1934) The Cambro-Ordovician formations and faunas of South Chosen. Palaeontology. Part II. Lower Ordovician faunas. Journal of the Faculty of Science, Imperial University of Tokyo. Section 2, 3, 521–585.
Kobayashi, T. (1940) Lower Ordovician fossils from Caroline Creek, near Latrobe, Mersey River district, Tasmania. Papers and Proceedings of the Royal Society of Tasmania, 1939, 67–76. (for 1939)
Kobayashi, T. (1955) The Ordovician fossils of the McKay Group in British Columbia western Canada, with a note on the early Ordovician palaeogeography. Journal of the Faculty of Science, Tokyo University, Section 2, 9, 355–493.
Kobayashi, T. (1960) The Cambro-Ordovician formations and faunas of South Korea, Part VI. Palaeontology V. Journal of the Faculty of Science, Tokyo University, Section 2, 12, 217–275.
Laurie, J.R. & Shergold, J.H. (1996) Early Ordovician trilobite taxonomy and biostratigraphy of the Emanuel Formation, Canning Basin, Western Australia. Part 1. Palaeontographica Abteilung A, 240, 65–103.
Lee, D.-C. & Chatterton, B. (1997) Ontogenies of trilobites from the Lower Ordovician Garden City Formation of Idaho and their implications for the phylogeny of the Cheirurina. Journal of Paleontology, 71, 683–702.
Legg, D.P. (1976) Ordovician trilobites and graptolites from the Canning Basin, Western Australia. Geologica et Palaeontologica, 10, 1–58.
Liu, Y.-R. (1982) [Trilobites]. In: (Ed.), [Paleontological Atlas of Hunan]. Geological Memoir 2, vol. 1, Beijing, pp. 290–347. (in Chinese)
Ludvigsen, R. (1975) Ordovician formations and faunas, southern Mackenzie Mountains. Canadian Journal of Earth Sciences, 12, 663–697.
McAdams, N.E.B. & Adrain, J.M. (2009a) New pliomerid trilobite genus Lemureops from the Lower Ordovician (Ibexian; Tulean, Blackhillsian) of western Utah, USA. Memoirs of the Association of Australasian Palaeontologists, 37, 491–540.
McAdams, N.E.B. & Adrain, J.M. (2009b) Phylogenetics of the Early Ordovician pliomerid trilobites Protopliomerella, Pseudocybele, and related taxa: Unravelling the base of the cheiruroidean radiation. GSA Abstracts with Programs, 41, 562.
McAdams, N.E.B. & Adrain, J. (2009c) Heckethornia, a new genus of dimeropygid trilobites from the Lower Ordovician (Ibexian; Tulean and Blackhillsian) of the Great Basin, western USA. Canadian Journal of Earth Sciences, 46, 875–914.
McAdams, N.E.B. & Adrain, J.M. (2010a) A new species of the Lower Ordovician pliomerid trilobite Pseudocybele and its biostratigraphic significance. Zootaxa, 2550, 21–38.
McAdams, N.E.B. & Adrain, J.M. (2010b) Phylogeny of the Early Ordovician trilobites Ibexaspis, Pseudomera, and related taxa: Reconstructing Pliomeridae from the ground up. GSA Abstracts with Programs, 42, 39.
Peng, S.-C. (1990) Tremadoc stratigraphy and trilobite faunas of northwestern Hunan. 2. Trilobites from the Panjiazui Formation and the Madaoyu Formation in Jiangnan Slope Belt. Beringeria, 2, 55–171.
Poulsen, C. (1927) The Cambrian, Ozarkian and Canadian faunas of northwest Greenland. Meddelelser om Grønland, 70, 235–343.
Přibyl, A., Vaněk, J. & Pek, I. (1985) Phylogeny and taxonomy of family Cheiruridae (Trilobita). Acta Universitatis Palackianae Olomucensis Facultas rerum naturalium, 83, 107–193.
Raymond, P.E. (1905) Note on the names Amphion, Harpina and Platymetopus. American Journal of Science, 19, 377–378.
Raymond, P.E. (1913) Subclass Trilobita. In: Eastman, C.R. (Ed.), Text-book of paleontology (2nd edition), Volume 1. MacMillan, New York, pp. 607–638.
Raymond, P.E. (1920) Some new Ordovician trilobites. Bulletin of the Museum of Comparative Zoology, Harvard, 64, 273–296.
Ross, R.J., Jr. (1949) Stratigraphy and trilobite faunal zones of the Garden City Formation, northeastern Utah. American Journal of Science, 247, 472–491.
Ross, R.J., Jr. (1951) Stratigraphy of the Garden City Formation in northeastern Utah, and its trilobite faunas. Peabody Museum of Natural History, Yale University, Bulletin, 6, 1–161.
Ross, R.J., Jr., Hintze, L.F., Ethington, R.L., Miller, J.F., Taylor, M.E. & Repetski, J.E. (1997) The Ibexian, lowermost series in the North American Ordovician. United States Geological Survey Professional Paper, 1579, 1–50.
Shaw, F.C. (1968) Early Middle Ordovician Chazy trilobites of New York. New York State Museum and Science Service Memoir, 17, 1–163.
Simpson, A.G., Hughes, N.C., Kopaska-Merkel, D.C. & Ludvigsen, R. (2005) Development of the caudal exoskeleton of the pliomerid trilobite Hintzeia plicamarginis new species. Evolution and Development, 7, 528–541.
Toro, M. & Monaldi, C.R. (1981) Benedettia huquensis nov. gen. et nov. sp. (Trilobita-Pliomeridae) de la Quebrada de Huaco, Provincia de San Juan. Asociación Geológica Argentina, Revista, 36, 236–239.
Vaccari, N.E. (2003) Trilobites de la Formación San Juan, Precordillera Argentina: Pliomeridae Raymond, 1913. Ameghiniana, 40, 239–248.
Waisfeld, B.G. & Vaccari, N.E. (2003) Trilobites. In: Benedetto, J.L. (Ed.), Ordovician Fossils from Argentina. Secretaría de Ciencia y Tecnología, Universidad Nacional de Córdoba, Cordoba, pp. 295–409.
White, R.D. & Lieberman, B.S. (1998) A type catalog of fossil invertebrates (Arthropoda: Trilobita) in the Yale Peabody Museum. Postilla. Yale Peabody Museum, 214, 1–151.
Whittington, H.B. (1961) Middle Ordovician Pliomeridae (Trilobita) from Nevada, New York, Quebec, Newfoundland. Journal of Paleontology, 35, 911–922.
Whittington, H.B. & Kelly, S.R.A. (1997) Morphological terms applied to Trilobita. In: Kaesler, R.L. (Ed.), Treatise on invertebrate paleontology. Part O. Arthropoda 1, Trilobita. Revised. Geological Society of America and University of Kansas Press, Lawrence, Kansas, pp. 313–329.
Wiman, C. (1908) Studien über das Nordbaltische Silurgebiet. Bulletin of the Geological Institution of the University of Uppsala, 8, 73–168.
Zhou, T.-M., Liu, Y.-R., Meng, X.-S. & Sun, Z.-H. (1977) [Trilobita]. In: [Palaeontological Atlas of Central and South China. I. Early Palaeozoic]. Beijing, 104–266. (in Chinese)