Proterocameroceras Ruedemann 1905
Genus Proterocameroceras Ruedemann, 1905 Type species Orthoceras brainerdi Whitfield, 1886, from Fort Cassin Formation, Floian, at Fort Cassin headland, Vermont; by original designation. Diagnosis Slender, gradually expanding orthocones with broadly elliptically depressed cross section; short chambe...
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Zenodo
2021
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| Online Access: | https://dx.doi.org/10.5281/zenodo.5793462 https://zenodo.org/record/5793462 |
| Summary: | Genus Proterocameroceras Ruedemann, 1905 Type species Orthoceras brainerdi Whitfield, 1886, from Fort Cassin Formation, Floian, at Fort Cassin headland, Vermont; by original designation. Diagnosis Slender, gradually expanding orthocones with broadly elliptically depressed cross section; short chambers; sutures directly transverse, slightly sinuous, forming gentle dorsal and ventral lobes; siphuncle large, almost marginal, circular cross section; connecting ring thick, concave segments; septal necks curved orthochoanitic to loxochoanitic; endosiphuncular deposits form endocones with narrow endosiphotube and three endosiphoblades (after Flower 1941; Ulrich et al. 1944: 55; Teichert 1964: K166). Remarks Numerous species have been assigned to Proterocameroceras , especially from the Early and Middle Ordovician of Russia (Balashov 1962, 1968) and South China (Xu & Lai 1987); some of them differ strongly from the type species. Proterocameroceras valhallfonnense sp. nov. (see below) is one of these forms. A revision of this genus is therefore desirable, but not within the scope of this monograph. : Published as part of Kröger, Björn & Pohle, Alexander, 2021, Early-Middle Ordovician cephalopods from Ny Friesland, Spitsbergen - a pelagic fauna with Laurentian affinities, pp. 1-102 in European Journal of Taxonomy 783 (1) on page 16, DOI: 10.5852/ejt.2021.783.1601, http://zenodo.org/record/5793422 : {"references": ["Flower R. H. 1941. Development of the mixochoanites. Journal of Paleontology 15: 523 - 548. Flower R. H. 1955. Status of endoceroid classification. Journal of Paleontology 29: 329 - 371. Available from https: // www. jstor. org / stable / 1300321 [accessed 19 Nov. 2021].", "Ulrich E. O., Foerste A. F., Miller A. K. & Unklesbay A. G. 1944. Ozarkian and Canadian cephalopods. Part III: Longicones and summary. Geological Society of America Special Papers 58: 1 - 226. https: // doi. org / 10.1130 / SPE 58", "Balashov E. G. 1962. Nautiloidei ordovika sibirskoi platformy. Izdatel'stvo Leningradskogo Universiteta, St. Petersburg.", "Balashov E. G. 1968. Endoceratoidei ordovika SSSR. Isdatelstvo Leningradskogo Universiteta, Leningrad.", "Xu G. - H. & Lai C. - G. 1987. Cephalopods. In: Wang X., Ni S., Zeng Q. et al. (eds) Biostratigraphy of the Yangtze Gorge Area, Volume 2, Early Palaezoic Area: 245 - 253. Geological Publishing House, Bejing."]} |
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