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Taxonomy and correlation of Lower Triassic (Spathian) segminate conodonts from Oman and revision of some species of Neospathodus

Published online by Cambridge University Press:  14 July 2015

M. J. Orchard
M. J. Orchard*
Affiliation:
Geological Survey of Canada, 100 West Pender Street, Vancouver, British Columbia V6B 1R8, Canada
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Abstract

Exceptionally well preserved Lower Triassic conodonts from Oman include an array of Neospathodus species, many of which are new. Those from the upper Lower Triassic, or Spathian, are described in conjunction with a restudy of conodont type material from Chios, Greece, and an assessment of contemporary collections from Pakistan and western North America. The taxonomic scope of three key species from Chios, Neospathodus homeri, N. triangularis, and N. gondolelloides, is revised. Seven new species are described from Oman: N. abruptus, N. brevissimus, N. brochus, N. crassatus, N. curtatus, N. pusillus, and N. symmetricus; and one new species, N. clinatus, is described from Pakistan. The allied Icriospathodus collinsoni is also described from Oman. The occurrence and range of Neospathodus species are presented in the context of the ammonoid succession in the Spathian of North America. Both N. homeri and N. triangularis, as revised, have shorter ranges and are more age diagnostic than previously thought. Neospathodus gondolelloides is a distinct taxon, and not synonymous with Chiosella timorensis. Five informal faunal divisions are identified based on Neospathodus and allied species. In ascending stratigraphic order, these are typified by Icriospathodus collinsoni, Neospathodus homeri, N. triangularis, N. symmetricus, and N. gondolelloides. Oman collections represent three of these faunas, which occur also in the Columbites through Prohungarites/Subcolumbites ammonoid beds of western U.S.A.

Type
Research Article
Information
Journal of Paleontology , Volume 69 , Issue 1 , January 1995 , pp. 110 - 122
Copyright
Copyright © The Paleontological Society 

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References

Assereto, R., Jacobshagen, V., Kauffmann, G., and Nicora, A. 1980. The Scythian/Anisian Boundary in Chios, Greece. Rivista Italiana di Paleontologia e Stratigrafia, 85:715–736.Google Scholar
Bender, H. 1970. Zur Gliederung der Mediterranen Trias II. Die Conodontenchronologie der Mediterranen Trias. Annales Geologiques des Pays Helleniques, 19:465–540.Google Scholar
Bender, H., and Kockel, C. W. 1963. Die Conodonten der Griechischen Trias. Annales Geologiques des Pays Helleniques, 46:437–448.Google Scholar
Bucher, H. 1989. Lower Anisian Ammonoids from the northern Humboldt Range (northwestern Nevada, USA) and their bearing upon the Lower-Middle Triassic boundary. Eclogae Geologicae Helvetiae, 8:945–1002.Google Scholar
Budurov, K. J., Gupta, V. J., Kachroo, R. K., and Sudar, M. N. 1986. Problems of the Lower Triassic conodont stratigraphy and the Permian-Triassic boundary. Società Geologica Italiana, Memorie 34:321–328.Google Scholar
Budurov, K. J., Sudar, M. N., and Gupta, V. J. 1987. Spathoicriodus, a new Early Triassic conodont genus. Bulletin of the Indian Geologists Association, 20:175–176.Google Scholar
Budurov, K. J., Sudar, M. N., and Gupta, V. J. 1988a. Kashmirella, a new Early Triassic conodont genus. Bulletin of the Indian Geologists Association, 21:107–112.Google Scholar
Budurov, K. J., Sudar, M. N., and Gupta, V. J. 1988b. Early Triassic parallel conodont zonation. Contributions to Himalayan Geology, 4:158–166.Google Scholar
Buryi, G. 1979. Lower Triassic conodonts of the South Primor'ye. Instituta Geologii i Geofiziki, Sibirskoe Otdelenie, Akadamie Nauk SSSR, Moscow, 142 p.Google Scholar
Buryi, G., Budurov, K. J., Sahni, A., Gupta, V. J., Kachroo, R. K., Chhabra, N. L., Ahluwalia, A. D., and Azmi, R. J. 1980. On the validity of the name Neospathodus gondolelloides (Bender, 1968). Bulletin of the Indian Geologists Association, 13:145–146.Google Scholar
Chhabra, N. L., and Sahni, A. 1981. Late Lower Triassic and early Middle Triassic conodont faunas from Kashmir and Kumaun sequences in Himalayas. Journal of the Paleontological Society of India, 25:135–147.Google Scholar
Clark, D. L., Paull, R. K., Solien, M. A., and Morgan, W. A. 1979. Triassic Conodont biostratigraphy in the Great Basin, p. 179–183. In Sandberg, C. A. and Clark, D. L. (eds.), Conodont Biostratigraphy of the Great Basin and Rocky Mountains. Brigham Young University Geology Studies, 6 (3).Google Scholar
Collinson, J. W., and Hasenmueller, W. A. 1978. Early Triassic paleogeography and biostratigraphy of the Cordilleran miogeosyncline, p. 175–187. In Howell, D. G. and McDougall, K. A. (eds.), Mesozoic Paleogeography of the Western United States. Pacific Coast Paleogeography Symposium 2.Google Scholar
Dagis, A. A. 1990. Lower Triassic Conodonta from the Southeastern Pamirs: fossil plates and explanatory text, p. 73–89. In Dagis, A. S. (ed.), Trias Sibiri. Trudy Instituta Geologii i Geofiziki (Novosibirsk), 767.Google Scholar
Ding, M. 1983. Lower Triassic conodonts from the Mountain Majiashan in Anhui Province and their stratigraphic significance. Journal of Wuhan College of Geology, 20(2):37–48.Google Scholar
Ding, M., and Huang, Q. 1990. Late Permian–Middle Triassic conodont fauna and paleoecology in Shitouchai, Ziyun County, Guizhou Province. Earth Science Journal of China University of Geosciences, 15:291–298.Google Scholar
Durkoop, A., Richter, D. K., and Stritzke, R. 1986. Fazies, Alter und Korrelation der triadischen Rotkalke von Epidauros, Adhami und Hydra (Griechenland). Facies, 14:105–150.CrossRefGoogle Scholar
Duan, J. Y. 1987. Permian-Triassic conodonts from southern Jiangsu and adjacent areas, with indexes of their color alteration. Acta Micropalaeontologica Sinica, 4:351–368.Google Scholar
Gaetani, M., Jacobshagen, V., Nicora, A., Kauffmann, G., Tselepidis, V., Fantini Sestini, N., Mertmann, D., and Skourtsis-Coroneou, V. 1992. The Early–Middle Triassic boundary at Chios (Greece). Rivista Italiana di Paleontologia e Stratigrafia, 98:181–204.Google Scholar
Gedik, I. 1975. Die Conodonten der Trias auf der Kocaeli-Halbinsel (Tuerkei). Palaeontographica Abteiling A, 150:99–160.Google Scholar
Hatleberg, E. W., and Clark, D. L. 1984. Lower Triassic conodonts and biofacies interpretations: Nepal and Svalbard. Geologica et Palaeontologica, 18:101–125.Google Scholar
Huckriede, R. 1958. Die Conodonten der mediterranen Trias und ihr stratigraphischer Wert. Paläontologische Zeitschrift, 32:141–172.CrossRefGoogle Scholar
Ishida, K. 1981. Fine stratigraphy and conodont biostratigraphy of a bedded chert member of the Nakagawa Group. Journal of Science, University of Tokushima, 14:107–137.Google Scholar
Koike, T. 1973. Triassic conodonts from Kedah and Pahang, Malaysia. Geology and Palaeontology of Southeast Asia, 12:91–113.Google Scholar
Koike, T. 1981. Biostratigraphy of Triassic conodonts in Japan. Science Reports of Yokohama National University, Section 2, 28:25–42.Google Scholar
Koike, T. 1992. Morphological variation in Spathian conodonts Spathoicriodus collinsoni (Solien) from the Taho Limestone, Japan, p. 355–364. In Ishizaki, K. and Saito, T. (eds.), Centenary of Japanese Micropaleontology. Terra Scientific Publishing Company, Tokyo.Google Scholar
Kozur, H. 1980. The main events in the Upper Permian and Triassic conodont evolution and its bearing to the Upper Permian and Triassic stratigraphy. Rivista Italiana di Paleontologia e Stratigrafia, 85:741–766.Google Scholar
Kozur, H. 1989. The taxonomy of the gondolellid conodonts in the Permian and Triassic. Courier Forschungsinstitut Senckenberg, 117:409–469.Google Scholar
Krahl, J., Kauffmann, G., Kozur, H., Richter, D., Foerster, O., and Heinritzi, F. 1983. Neue Daten zur Biostratigraphie und zur tektonischen Lagerung der Phyllit-Gruppe und der Trypali-Gruppe auf der Insel Kreta (Griechenland). Geologische Rundschau, 72:1147–1166.CrossRefGoogle Scholar
Kummel, B. 1954. Triassic stratigraphy of southeastern Idaho and adjacent areas. U.S. Geological Survey, Professional Paper 254–H:165–194.Google Scholar
Kummel, B. 1966. The Lower Triassic Formations of the Salt Range and Trans-Indus Ranges, Pakistan. Bulletin of the Museum of Comparative Zoology, 34:361–429.Google Scholar
Kummel, B. 1969. Ammonoids of the Late Scythian (Lower Triassic). Bulletin of the Museum of Comparative Zoology, 137:311–702.Google Scholar
Matsuda, T. 1983. Early Triassic conodonts from Kashmir, India. Part 3: Neospathodus 2. Journal of Geosciences, Osaka City University, 26(4):87–110.Google Scholar
Matsuda, T. 1985. Late Permian to Early Triassic conodont paleobiogeography in the “Tethys Realm,” p. 157–170. In Nakasawa, K. and Dickens, J. M. (eds.), The Tethys, Her Paleogeography and Paleobiogeography from Paleozoic to Mesozoic. Tokai University Press, Tokyo.Google Scholar
McKelvey, V. E., and Strobell, J. D. Jr. 1955. Preliminary geological maps of the Paris–Bloomington Vanadium area, Bear Lake County, Idaho. U.S. Geological Survey, Mineral Investigations Field Studies Map MF 41.Google Scholar
Metcalfe, I. 1990. Triassic conodont biostratigraphy in the Malay Peninsula. Bulletin of the Geological Society of Malaysia, 26:133–145.CrossRefGoogle Scholar
Mietto, P., Fratoni, R. P., and Perri, M. C. 1991. Spathian and Aegean conodonts from the Capelluzzo Calcarenites of the Monte Facito Group (Lagonegro Sequence-southern Apennines). Memorie di Scienze Geologiche, Universita di Padova, 43:305–317.Google Scholar
Mosher, L. C. 1968. Triassic conodonts from western North America and Europe and their correlation. Journal of Paleontology, 42:895–946.Google Scholar
Mosher, L. C. 1973. Triassic conodonts from British Columbia and the northern Arctic Islands. Geological Survey of Canada, Bulletin 222:141–193.CrossRefGoogle Scholar
Nazarevich, B. P., and Zawidzka, K. 1981. Lower Triassic conodonts from the eastern Caucasian Foreland. Acta Geologica Polonica, 31:35–40.Google Scholar
Nichols, K. M., and Silberling, N. J. 1977. Stratigraphy and depositional history of the Star Peak Group (Triassic), northwestern Nevada. Geological Society of America, Special Paper 178, 73 p.Google Scholar
Orchard, M. J. 1992. Lower Triassic conodonts from Oman. Geological Society of America, Abstracts with Programs, 24(3):57–58.Google Scholar
Orchard, M. J. 1994. Conodont biochronology around the Early-Middle Triassic boundary: new data from North America, Oman and Timor. Mémoire de Géologie, Lausanne, 22:105–114.Google Scholar
Orchard, M. J., and Bucher, H. 1992. Conodont-ammonoid intercalibration around the Lower-Middle Triassic boundary: Nevadan clocks help tell British Columbian time. Geological Survey of Canada, Current Research, Paper 92–1E:133–140.CrossRefGoogle Scholar
Perri, M. C. 1986. A Spathian conodont fauna from the Cencenighe Member of Werfen Formation (Scythian), southeastern Dolomites, Italy. Bollettino Societa Paleontologica Italiana, 24:23–28.Google Scholar
Perri, M. C., and Andraghetti, M. 1987. Permian-Triassic boundary and Early Triassic conodonts from the southern Alps, Italy. Rivista Italiana di paleontologia e Stratigrafia, 93:291–328.Google Scholar
Perry, D. G., and Chatterton, B. D. E. 1979. Late Early Triassic brachiopod and conodont fauna, Thaynes Formation, southeastern Idaho. Journal of Paleontology, 53:307–319.Google Scholar
Silberling, N. J., and Tozer, E. T. T. 1968. Biostratigraphic classification of the marine Triassic in North America. Geological Society of America, Special Paper 110, 63 p.Google Scholar
Solien, M. A. 1979. Conodont biostratigraphy of the Lower Triassic Thaynes Formation, Utah. Journal of Paleontology, 53:276–306.Google Scholar
Sweet, W. C. 1970. Uppermost Permian and Lower Triassic conodonts of the Salt Range and Trans-Indus Ranges, West Pakistan, p. 207–275. In Kummel, B. and Teichert, C. (eds.), Stratigraphic Boundary Problems, Permian and Triassic of West Pakistan. University of Kansas, Department of Geology Special Publications, 4.Google Scholar
Sweet, W. C. 1973. Genus Neospathodus Mosher, 1968, p. 155–194. In Ziegler, W. (ed.), Catalogue of Conodonts. I. E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart.Google Scholar
Sweet, W. C. 1988. A quantitative conodont biostratigraphy for the Lower Triassic. Seckenbergiana lethaea, 69:253–273.Google Scholar
Sweet, W. C., Mosher, L. C., Clark, D. L., Collinson, J. W., and Hasenmueller, W. H. 1971. Conodont biostratigraphy of the Triassic, p. 441–465. In Sweet, W. C. and Bergstrom, S. M. (eds.), Symposium on Conodont Biostratigraphy. Geological Society of America, Memoir, 127.Google Scholar
Tozer, E. T., and Calon, T. J. 1990. Triassic ammonoids from Jabal Safra and Wadi Alwa, Oman, and their significance, p. 203–211. In Robertson, A. H. F., Searle, M. P. and Ries, A. C. (eds.), The Geology and Tectonics of the Oman Region. Geological Society Special Publication, 49.Google Scholar
Wang, Z.-H. 1982. Discovery of fauna with Neospathodus timorensis of the Lower Triassic of Zigun, Guizhou. Acta Palaeontologica Sinica, 21:584–587.Google Scholar
Wang, Z.-H., and Cao, Y.-Y. 1981. Early Triassic conodonts from Lichuan, western Hubei. Acta Palaeontologica Sinica, 20:363–375.Google Scholar
Wang, Z.-H., and Dai, J.-Y. 1981. Triassic conodonts from Jiangyou-Beichuan area, Sichuan Province. Acta Palaeontologica Sinica, 20:138–152.Google Scholar
Zakharov, Y. D., and Rybalka, S. V. 1987. A standard for the Permian–Triassic in the Tethys, p. 6–48. In Zakharov, Y. D.Y. D., and Unoprienko, Y. I. (eds.), Problems of the Permian and Triassic Biostratigraphy of East USSR. USSR Academy of Science, Far Eastern Scientific Centre, Vladivostock.Google Scholar