683 results on '"Zalasiewicz, Jan"'
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202. From the depths of the Earth
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Zalasiewicz, Jan, primary
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- 2010
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203. To the rendezvous
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Zalasiewicz, Jan, primary
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- 2010
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204. Distant lands
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Zalasiewicz, Jan, primary
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- 2010
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205. Breaking the surface
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Zalasiewicz, Jan, primary
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- 2010
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206. Ghosts in absentia
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Zalasiewicz, Jan, primary
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- 2010
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207. The oil window
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Zalasiewicz, Jan, primary
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- 2010
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208. Where on Earth?
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Zalasiewicz, Jan, primary
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- 2010
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209. Die Indizienkette
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Zalasiewicz, Jan, primary
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- 2009
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210. Widerhall
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Zalasiewicz, Jan, primary
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- 2009
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211. Hochwasser, Niedrigwasser
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Zalasiewicz, Jan, primary
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- 2009
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212. Dynastien
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Zalasiewicz, Jan, primary
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- 2009
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213. Spuren
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Zalasiewicz, Jan, primary
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- 2009
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214. Die Erde nach uns
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Zalasiewicz, Jan, primary
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- 2009
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215. A Geological History of Climate Change
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Zalasiewicz, Jan, primary and Williams, Mark, additional
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- 2009
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216. Der tektonische Aufzug
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Zalasiewicz, Jan, primary
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- 2009
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217. In 100 Millionen Jahren
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Zalasiewicz, Jan, primary
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- 2009
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218. Das Treffen
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Zalasiewicz, Jan, primary
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- 2009
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219. Der Blickwinkel
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Zalasiewicz, Jan, primary
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- 2009
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220. Contributors
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Tuckett, Richard P., primary, Cohen, Shabtai, additional, Dorman, Lev I., additional, Stenchikov, Georgiy, additional, Lourens, Lucas J., additional, Tuenter, Erik, additional, Zalasiewicz, Jan, additional, Williams, Mark, additional, Reichler, Thomas, additional, Trigo, Ricardo M., additional, Gimeno, Luis, additional, Fiedler, Wolfgang, additional, Humphries, Murray M., additional, Pelini, Shannon L., additional, Prior, Kirsten M., additional, Parker, Derrick J., additional, Dzurisin, Jason D.K., additional, Hellmann, Jessica J., additional, Lindroth, Richard L., additional, Edwards, Martin, additional, Attrill, Martin J., additional, Worm, Boris, additional, Lotze, Heike K., additional, Mieszkowska, Nova, additional, Morecroft, Michael D., additional, Keith, Sally A., additional, Dixon, Geoffrey R., additional, Gehrels, Roland, additional, Kanzow, T., additional, Visbeck, M., additional, Turley, Carol, additional, Findlay, Helen S., additional, Vaughan, David G., additional, Aptroot, Andre, additional, Nicholls, Robert J., additional, Woodroffe, Colin, additional, Burkett, Virginia, additional, Garrett, Karen A., additional, Nita, M., additional, Wolf, E.D. De, additional, Gomez, L., additional, and Sparks, A.H., additional
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- 2009
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221. Clingfilm preservation of spiraliform graptolites: evidence of organically sealed Silurian seafloors
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Jones, Helen, Zalasiewicz, Jan, and Rickards, Barrie
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Shale -- Research ,Ocean bottom -- Research ,Diagenesis -- Research ,Animals, Fossil -- Research ,Graptolites ,Earth sciences - Abstract
The Early Silurian graptolites Spirograptus turriculatus and Sp. guerichi are typically preserved in condensed graptolite shale lithologies as entirely flattened outlines; all whorls are visible and little or no sediment infills the originally cone-shaped rhabdosomes, as though the graptolites had been sealed in clingfilm, or plastic wrap, prior to burial and compaction. By contrast, the rhabdosomes of graptolites transported in turbidity currents typically are filled with sediment. The most likely reason for the clingfilm mode of preservation is encasement or covering of the graptolite rhabdosomes by marine snow and/or microbial mats prior to burial by clastic sediment and compaction on an anoxic seafloor. Experimental evidence reported herein supports this suggestion. The organic material that mediated the preservation of such graptolites was likely akin to, but probably physically stronger than, the delicate benthic flocculation layer of the current Black Sea floor. Like the latter, it probably formed significant microtopography at and just below the sediment-water interface and mediated geologic processes such as early diagenesis in graptolite shale lithologies. Keywords: graptolites, black shales, marine snow, microbial mats.
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- 2002
222. Body of Evidence
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Zalasiewicz, Jan, primary
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- 2008
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223. Traces
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Zalasiewicz, Jan, primary
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- 2008
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224. High Water, Low Water
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Zalasiewicz, Jan, primary
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- 2008
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225. Perspective
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Zalasiewicz, Jan, primary
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- 2008
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226. The Strata Machine
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Zalasiewicz, Jan, primary
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- 2008
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227. 100 Million Years AD
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Zalasiewicz, Jan, primary
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- 2008
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228. Dynasties
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Zalasiewicz, Jan, primary
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- 2008
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229. Meeting the People
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Zalasiewicz, Jan, primary
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- 2008
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230. The Earth After Us
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Zalasiewicz, Jan, primary
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- 2008
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231. Tectonic Escalator
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Zalasiewicz, Jan, primary
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- 2008
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232. Echoes
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Zalasiewicz, Jan, primary
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- 2008
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233. Invasive mollusc faunas of the River Thames exemplify biostratigraphical characterization of the Anthropocene
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Himson, Stephen J., primary, Kinsey, Naome P., additional, Aldridge, David C., additional, Williams, Mark, additional, and Zalasiewicz, Jan, additional
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- 2020
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234. Graptolites from Silurian (Llandovery Series) Sedimentary Deposits Attributed to a Forearc Setting, Co to Formation, Co to Archipelago, Northeast Vietnam
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Saparin, Muhammad Aqqid, primary, Williams, Mark, additional, Zalasiewicz, Jan, additional, Komatsu, Toshifumi, additional, Rushton, Adrian, additional, Doan, Hung Dinh, additional, Trinh, Ha Thai, additional, Nguyen, Hung Ba, additional, Nguyen, Minh Trung, additional, and Vandenbroucke, Thijs R. A., additional
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- 2020
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235. Macrofabric fingerprints of late Devonian--early Carboniferous subduction in the polish Variscides, the Kaczawa complex, Sudetes
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Collins, Alan S., Kryza, Ryszard, and Zalasiewicz, Jan
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Poland -- Natural history ,Geology -- Research ,Earth sciences - Abstract
We describe a remarkably preserved assemblage of sedimentary and tectonic fabrics in cores from the Kaczawa complex, Sudetes, SW Poland. These fabrics indicate a continuum of process from repeated remobilization of Upper Devonian--Lower Carboniferous muddy flysch and volcaniclastic sediments as debris flows and olistostromes, to fracturing, fluid-streaming and soft-sediment injection triggered by high pore-water pressures during the initial stages of tectonic deformation, to contractional cleavage formation and local cataclasis while the sediment was still only partially consolidated. These structures are similar to those described from ODP cores through the toes of active accretionary prisms. They indicate active subduction of oceanic crust during the Late Devonian, suggesting that ophiolite obduction and significant overthrusting in the Sudetes occurred as an integral part of the Variscan orogeny. Keywords: Sudetes, Kaczawa complex, melange, soft-sediment deformation.
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- 2000
236. Benthic foraminifera indicate Glacial North Pacific Intermediate Water and reduced primary productivity over Bowers Ridge, Bering Sea, since the Mid-Brunhes Transition
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Kender, Sev, primary, Aturamu, Adeyinka, additional, Zalasiewicz, Jan, additional, Kaminski, Michael A., additional, and Williams, Mark, additional
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- 2019
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237. Commentary on the “Anthropocene in Chile” Manifesto
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Zalasiewicz, Jan, primary
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- 2019
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238. 27. Graptolites: Patterns of Diversity Across Paleolatitudes
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Cooper, Roger A., primary, Maletz, Jörg, additional, Taylor, Lindsey, additional, and Zalasiewicz, Jan A., additional
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- 2004
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239. Gothograptus , Frech 1897
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Kozłowska, Anna, Bates, Denis, Zalasiewicz, Jan, and Radzevičius, Sigitas
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Graptoloidea ,Hemichordata ,Gothograptus ,Animalia ,Retiolitidae ,Biodiversity ,Graptolithina ,Taxonomy - Abstract
Genus Gothograptus Frech, 1897 Type species. Retiolites nassa Holm, 1890, pl. 2, fig. 12, 13; NRM-PZ Cn0025546 Type locality. Gotland, Sweden, Wenlock, upper Homerian, Gothograptus nassa Biozone (Holm, 1890). Emended diagnosis. Streamlined shape of tubarium ended by appendix. Ancora umbrella with undulating rim. Sicula about 1.2–1.5 mm long. Proximal lateral and ventral orifices small, kidney-shaped on lateral side and triangular on ventral sides of tubarium. Lateral wall on reverse sides of tubarium built of stronger oblique lists, whereas obverse wall is composed of the nema and connecting rods. Semigothograptus and Neogothograptus differ from Gothograptus in having a free nema. Ventral wall composed of distinctive lips, genicular lists, pleural lists and mid-ventral lists. Singular genicular processes forming solid or reticulated hoods or veils, which may cover the thecal orifice and ventral wall of thecae. In mature specimens a dense and thick reticulum, very thick ancora lists, a thick sicular rim, and reticular structures surrounding the metasicula may occur. Species included. Gothograptus nassa (Holm, 1890); Gothograptus pseudospinosus (Eisenack, 1951), Gothograptus kozlowskii Kozłowska-Dawidziuk, 1990; Gothograptus obtectus Kozłowska-Dawidziuk, 1990; Gothograptus storchi Lenz & Kozłowska, 2006; Gothograptus auriculatus n. sp.; Gothograptus domeyki n. sp.; Gothograptus velo n. sp., Gothograptus diminutus n. sp. Remarks. There are some problems with the designation of some Gothograptus species illustrated or described in the past. Jaeger illustrated and temporarily named, on an unpublished range chart for retiolitids, several species from North German glacial erratic boulders (Maletz 2008, fig. 1). These species were never described or published by Jaeger. Based on Jaeger‘s data Maletz (2008) regarded most of the species as nomina nuda or not identified. One of them, G. eximinassa was included in the genus Neogothograptus (Maletz 2008). The species G. praenassa was not identified. Later on Jaeger‘s G. gigantonassa was included in Semigothograptus meganassa (Rickards & Palmer, 2002) (Kozłowska 2016). According to Jaeger‘s drawing, the material that he referred to G. osgaleae may be included in G. obtectus, whereas the specimens described as G. nassa and G. pseudospinosus are properly designated (Kozłowska personal observation). G. pseudospinosus Eisenack, 1951 was described from a Baltic erratic boulder with no detailed stratigraphical designation (Eisenack 1951). On his range chart of graptolites from the Wenlock of Germany, Jaeger (1991) placed this species in the lundgreni/testis Biozone, but did not describe the material. Thus G. pseudospinosus needs more detailed study., Published as part of Kozłowska, Anna, Bates, Denis, Zalasiewicz, Jan & Radzevičius, Sigitas, 2019, Evolutionary significance of the retiolitine Gothograptus (Graptolithina) with four new species from the Silurian of the East European Platform (Baltica), Poland and Lithuania, pp. 435-469 in Zootaxa 4568 (3) on pages 446-447, DOI: 10.11646/zootaxa.4568.3.2, http://zenodo.org/record/2601607, {"references":["Frech, F. (1897) Lethaea Geognostica 1. Lethaea Palaeozoica. E Schweizerbart'sche Verlagshandlung, Stuttgart, 690 pp.","Holm, G. (1890) Gotlands graptoliter. Svenska Vetenskap-Akademiens handlingar, 16, 1 - 34.","Eisenack, A. (1951) Retioliten aus dem Graptolithengestein. Palaeontographica, 100, 129 - 163.","Kozlowska-Dawidziuk, A. (1990) The genus Gothograptus (Graptolithina) from the Wenlock of Poland. Acta Palaeontologica Polonica, 35, 191 - 209.","Lenz, A. C. & Kozlowska, A. (2006) Graptolites from the lundgreni Biozone (Lower Homerian, Silurian), Arctic Islands, Canada: new species and supplementary material. Journal of Paleontology, 80, 616 - 637. https: // doi. org / 10.1666 / 0022 - 3360 (2006) 80 [616: GFTLBL] 2.0. CO; 2","Maletz, J. (2008) Retiolitid graptolites from the collection of Hermann Jaeger in the Museum fur Naturkunde, Berlin (Germany). I. Neogothograptus and Holoretiolites. Palaontologische Zeitschrift, 82, 285 - 307. https: // doi. org / 10.1007 / BF 02988896","Rickards, R. B. & Palmer, D. C. (2002) Gothograptus? meganassa sp. nov., an unusually large retiolitid graptoloid from the Late Wenlock ludensis Biozone of Long Mountain, Shropshire, UK. Special Papers in Palaeontology, 67, 225 - 232.","Kozlowska, A. (2016) A new generic name, Semigothograptus, for Gothograptus? meganassa Rickards & Palmer, 2002, from the Silurian post- lundgreni Biozone recovery phase, and comparative morphology of retiolitids from the lowermost upper Homerian (upper Wenlock). Zootaxa, 4208, 534 - 546. https: // doi. org / 10.11646 / zootaxa. 4208.6.2","Jaeger, H. (1991) Neue Standard-Graptolithenzonenfolge nach der \" Grossen Krise \" und der Wenlock / Ludlow-Grenze (Silur). Neues Jahrbuch fur Geologie und Palaontologie-Abhandlungen, 182, 303 - 354. [in German with English abstract] https: // doi. org / 10.1127 / njgpa / 182 / 1991 / 303"]}
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- 2019
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240. Gothograptus nassa
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Kozłowska, Anna, Bates, Denis, Zalasiewicz, Jan, and Radzevičius, Sigitas
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Graptoloidea ,Hemichordata ,Gothograptus ,Gothograptus nassa ,Animalia ,Retiolitidae ,Biodiversity ,Graptolithina ,Taxonomy - Abstract
Gothograptus nassa (Holm, 1890) Figs 10–12 1890 Retiolites nassa Holm, p. 25, pl. 2, figs 12–14. 1891 Gothograptus nassa Holm, Frech, pp. 670–671, fig. 223, 5–6. ?1900 Retiolites nassa Holm (Gothograptus, Frech), Wood, p. 486, fig. 27. 1908 Retiolites (Gothograptus) nassa (Holm), Ellis & Wood, pp. 343–344, fig. 225, pl. 34, figs 15a,d. ?1952 Gothograptus nassa (Holm, 1890), Bouček & Münch, pp. 11–15, fig. 2, a–i. 1952 Gothograptus intermedius Bouček & Münch, pp. 15–16, fig. 3 e–f. 1956 Gothograptus nassa (Holm, 1890), Tomczyk, pp. 42–44, fig. 8. 1979 Gothograptus nassa (Holm, 1890), Obut & Zaslavskaya, pp. 30–33, figs 1–4. 1999 Gothograptus nassa (Holm, 1890), Kozłowska-Dawidziuk, fig. 3. Material. The specimens of Gothograptus nassa studied come from Lithuania, Poland and Gotland. Material from Lithuania comes from the Šiupyliai-69 core, nassa Biozone (above parvus), at depths from 998.4 m to 997.0 m yielding 130 specimens and the Kybartai-14 core, depth 1087.8 m, a few specimens. The material from Poland, Bartoszyce IG-1 well, comes from the interval 1661.0 m to 1643.9 m, representing the parvus / nassa, dubius / nassa, and lower part of the praedeubeli biozones (see range chart in Porębska et al. 2006, fig. 2). The material is rich, containing about 2,000 specimens, representing different stages of growth of colonies. The Swedish material comes from Gotland, Blåhäll, locality 813–832, Blåhäll 1 (Spjeldnaes 1984), Dapps and Tegelbruk. Description. The tubaria represent mostly fragments of colonies at different stages of growth. The longest tubarium of 18 pairs of thecae is 2.8 cm long. It is an immature colony as it has not developed an appendix, and the distal part is not densely reticulated (Fig. 10A). The tubarium of Gothograptus nassa is almost parallel-sided. It widens from a proximal width of about 1.0 mm below the orifice of the first theca and reaches its maximum width (~ 1.2–1.4 mm) in the middle part of the tubarium, following which it tapers distally. The sicula length is about 1.4–1.5 mm. The mature tubaria have thick reticulum surrounding proximal lateral and ventral orifices (Fig. 4 H). There is a strong metasicular rim and reticulum around the sicula, which may represent the walls of th1 1 and th1 2. In some specimens a part of the membrane of the sicula is preserved. An outer ancora is rarely developed in mature specimens (Figs 4F, 12D). Genicular hoods of nassa type are developed successively during astogeny. The new, rich material illustrates hood development through the successive stages of the astogeny of colonies. Hoods are well developed in all thecae in mature colonies (Fig. 12). The appearance of the first genicular hood in young G. nassa colonies may be on different thecae (Fig. 10). Young tubaria of up to six pairs of thecae usually do not have hoods developed. The first genicular hood may appear on the proximal or medial part of the tubarium. Thus some tubaria do not have hoods on several pairs of thecae but tubaria with e.g. eight pairs of thecae may already have well-developed hoods on six proximal thecae. The longest sub-mature tubarium with eighteen pairs of thecae represents the intermediate stage of colony growth. It has larger hoods in the middle part of the tubarium (Fig. 12A, C, I). The size of hoods increases during astogeny; in mature colonies the larger hoods, especially in the distal part of the tubarium, cover the thecal orifices for some distance below. The largest hoods are usually located in the medial part of colonies (Fig. 12A, I). The distal thecae are shorter and their genicular hoods are irregular. The rich material of different stages of astogenetic growth of G. nassa colonies also shows a marked variability in the shape of hoods from almost rectangular to ovate (Fig. 12A, C). In mature colonies the clathrial and reticular lists have similar thicknesses. The proximal orifices, both ventral and lateral in old colonies, are partly overgrown by some reticular lists. The nema is thicker at the distal end, and extends about 0.5–0.7 mm out of the tubarium. The appendix is well developed, about 1.5 mm long. Remarks. The thickened sicular rim and sicular reticulum, as well as an outer ancora umbrella, were first described by Bates & Kirk (1978, p. 431, pls. 2, 6–7). Obut and Zaslavskaya (1979) described the astogeny of Gothograptus nassa based on material from the deep 1-R core of from the Kaliningrad District of the Peribaltic Syncline, from the nassa Biozone. Based on the specimens illustrated by Bouček & Münch (1952, figs. 3e, f) at various stages of growth, co-occurring with G. nassa, the authors established that Gothograptus intermedius Bouček & Münch, 1952 represents young stages of growth of G. nassa. The observations presented herein, based on material from the cores of Lithuania and Poland, support this judgement., Published as part of Kozłowska, Anna, Bates, Denis, Zalasiewicz, Jan & Radzevičius, Sigitas, 2019, Evolutionary significance of the retiolitine Gothograptus (Graptolithina) with four new species from the Silurian of the East European Platform (Baltica), Poland and Lithuania, pp. 435-469 in Zootaxa 4568 (3) on pages 447-451, DOI: 10.11646/zootaxa.4568.3.2, http://zenodo.org/record/2601607, {"references":["Holm, G. (1890) Gotlands graptoliter. Svenska Vetenskap-Akademiens handlingar, 16, 1 - 34.","Spjeldnaes, N. (1984) Epifauna as a tool in autecological analysis of Silurian brachiopods. Special Papers in Palaeontology, 32, 225 - 235.","Bates, D. E. B. & Kirk, N. H. (1978) Contrasting modes of construction of retiolite-type rhabdosomes. Acta Palaeontologica Polonica, 23, 427 - 465.","Obut, A. M. & Zaslavskaya, N. M. (1979) Razvitie rabdosom i ekologiya Gothograptus nassa (Holm). In: Betekhtina A. O. & Zhuravleva, T. I. (Eds.), Sreda i Zhihn v Geologicheskom Proshlom. Vol. 43, Vaprosy Ekostratigrfii. Nauka, Siberian Branch, Novosibirsk, pp. 30 - 33. [in Russian]","Boucek, B. & Munch, A. (1952) Retioliti stredoevropskeho svrchniho wenloku a ludlowu. Sbornik Ustredniho Ustavu geologickeho 19, oddil paleontologicky, 1 - 151."]}
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- 2019
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241. Gothograptus domeyki Koz��owska & Bates & Zalasiewicz & Radzevi��ius 2019, n. sp
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Koz��owska, Anna, Bates, Denis, Zalasiewicz, Jan, and Radzevi��ius, Sigitas
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Graptoloidea ,Gothograptus domeyki ,Hemichordata ,Gothograptus ,Animalia ,Retiolitidae ,Biodiversity ,Graptolithina ,Taxonomy - Abstract
Gothograptus domeyki n. sp. Figs 15���16 ?1952 Gothograptus nassa, Bouček & M��nch, pp. 11���15, fig. 2, a���i. Type material. Holotype number VU RET-13, mature specimen with seven pairs of thecae and appendix (Fig. 16 A���B), ��iupyliai-69 core, 1009,1 m, lundgreni Biozone, paratype number VU RET-14, finite tubarium (Fig. 16 C���E), ��iupyliai-69 core, depth 1010.0 m, lundgreni Biozone, Lithuania. Etymology. Ignacy Domeyko (1802���1889) was a Polish geologist, mineralogist and educator; most of his life was spent in Chile. Diagnosis. Gothograptus with genicular hoods of nassa type developed on the first pair of thecae; second pair of thecae may have paired spines with seams or remnants of reticulum between them; subsequent thecae lacking genicular processes except for the last theca with a reticulated hood. Distinctively thicker thecal lips than pleural and genicular lists. G othograptus domeyki differs from other Gothograptus species in the lack of genicular structures in the medial and distal thecae. Remarks. Gothograptus domeyki n. sp. differs from other Gothograptus species in the lack of any genicular processes in most thecae as well as in having thick lips. G. domeyki n. sp. is similar to G. kozlowskii in having nassa type hoods on the first pair of thecae and reticulated hoods on the last pair of thecae. Similar reticulated hoods on the last thecae are also found in G. storchi. G. domeyki n. sp. is so far known only from Lithuania. Bouček & M��nch (1952) described some retiolitines as Gothograptus nassa, from the Czech Republic, lundgreni Biozone. Their drawings show some tubaria with thick lips, and without genicular nassa hoods, similar to those described herein for the first time in G. domeyki n. sp. Proper recognition of this form needs some detailed study. Material. Two cores from Lithuania: ��iupyliai-69 core, depths: 1009.7 m 30 young, 12 mature; 1009.1 m 50 young, 31 mature; Vilkavi��kis-131 core, depth 1095.8 m four fragments of mature specimens. Upper part of lundgreni Biozone. Description. Mature tubaria usually have seven or eight pairs of thecae and appendix. The total length of the tubarium is about 7.0 mm, together with the appendix. The tubarium is almost parallel-sided, widest at 0.83 mm at the level of the first thecal pair, and then it slowly narrows to 0.4 mm just below the appendix. In some mature specimens the prongs of the ancora, as well as the sicular rim and lists above the proximal lateral orifices, are extremely thick ((Fig. 16A, B, E, H, I). An outer ancora is well developed in mature specimens. The proximal ventral orifices are overgrown by reticulum in mature colonies. Mid-ventral lists are 0.5 mm long in the first and last thecae, the rest are about 0.7 mm long. Genicular structures start to develop when the colony reaches about five thecal pairs. There are three types of genicular structures in mature tubaria of G. domeyki n. sp. The first pair of thecae have nassa hoods; usually they are small and do not cover the orifices of thecae or they are slightly larger than the thecal orifice. The second and third thecal pairs have a pair of curved spines grown on the pleural lists, extending horizontally. Seams on the inner sides of the spines indicate that there was a thin membrane between them, so that the spines form the sides of a hood. The bases of the spines in the mature tubaria are of triangular shape (Fig. 16G). Similar spines forming hoods are also found in Gothograptus kozlowskii (see below). The next thecae have no hoods; their lips are thick, about twice as thick as the geniculum list. The genicular lists became significantly thinner in the last thecae. The last pair of thecae have reticulated hoods covering orifices; the genicular list is not developed. The reticulum of these hoods is connected with the appendix (Fig. 16A). umbrella, outside view. Some young tubaria with five pairs of thecae have reticulum up to the third pair of thecae, small nassa hoods on the first thecae, the two next pairs of thecae having thin genicular spines. A specimen with seven pairs of thecae has a well-developed reticulum, except on the two last thecae. The lists of young colonies are thin; the thickest is the nema (Fig. 15A, D). During astogeny the next thicker lists are the lateral apertural rods. The lips and genicular lists are so thick that the thecal orifice is very narrow (Fig. 15E, 16E). The thecal orifices vary in shape from nearly rectangular to pyramidal with rounded corners (Fig. 7A, 16C, E). Mature colonies have a dense reticulum of similar thickness to the clathrial lists, thus the structures formed by clathrial lists are difficult to distinguish., Published as part of Koz��owska, Anna, Bates, Denis, Zalasiewicz, Jan & Radzevi��ius, Sigitas, 2019, Evolutionary significance of the retiolitine Gothograptus (Graptolithina) with four new species from the Silurian of the East European Platform (Baltica), Poland and Lithuania, pp. 435-469 in Zootaxa 4568 (3) on pages 454-457, DOI: 10.11646/zootaxa.4568.3.2, http://zenodo.org/record/2601607, {"references":["Boucek, B. & Munch, A. (1952) Retioliti stredoevropskeho svrchniho wenloku a ludlowu. Sbornik Ustredniho Ustavu geologickeho 19, oddil paleontologicky, 1 - 151."]}
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- 2019
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242. Gothograptus velo Kozłowska & Bates & Zalasiewicz & Radzevičius 2019, n. sp
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Kozłowska, Anna, Bates, Denis, Zalasiewicz, Jan, and Radzevičius, Sigitas
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Graptoloidea ,Hemichordata ,Gothograptus ,Animalia ,Retiolitidae ,Biodiversity ,Gothograptus velo ,Graptolithina ,Taxonomy - Abstract
Gothograptus velo n. sp. Fig. 22 1990. Gothograptus (Gothograptus) sp. A. Kozłowska-Dawidziuk, pp. 202–203, pl. 24: 2; fig. 6A–E. Type material. Mature tubarium, holotype ZPAL G.XIII/35, Zawada 1 core, depth 1533.3–1540 m, Poland, upper part of lundgreni Biozone. Material. One finite tubarium with nine pairs of thecae. Diagnosis. Proximal thecae with no genicular structures, successive medial and distal thecae have genicular veils. The veils are built of thin reticular lists; there are no thicker lists at the end of the veil as in G. obtectus. Reticulum below thecal lip undergoes reduction in distal thecae. Description. The mature tubarium has nine pairs of thecae. The distal end is slightly damaged, together with the appendix (Fig. 22). The tubarium length is 10.1 mm, together with the extending nema. The width of the tubarium at the level of the first pair of thecae is 0.8 mm. The widest part of the tubarium is 1.2 mm at the level of the fifth thecal pair. The tubarium tapers distally to a width of 0.6 mm at the level of the ninth pair of thecae. The sicula length is 1.5 mm; the prosicula apex is connected to the lateral wall of the tubarium at the level of the lip of th1 2. The thecal lips are thick whereas the genicular lists are thinner in distal thecae but well developed and easy to distinguish (Fig. 22B). The two first pairs of thecae do not have genicular structures. The first well-developed veil is on the fifth pair of thecae. Some reticular lists of the veil of th6 1 are connected to the geniculum of th5 1, and to the reticulum of the th5 1 veil (Figs 9C, 22B). The reticulum of the ventral thecal wall is well-developed up to the fifth pair of thecae, but distally, below the long veils, it become poorly developed, eventually disappearing under the veils of the last thecal pairs. The genicular and mid-ventral lists below the veils exhibit a similar decrease in thickness, becoming as thin as some lists of the veil (Figs 9C, 22B). The outer ancora is well-developed in the mature tubarium, and built of thick reticulum (Fig. 22D). Some membrane of the metasicular wall is connected to the virgella (Fig. 22C). Proximal internal structures typical of the genus Gothograptus are present, but they are difficult to distinguish in the flattened material to hand. The nema is distinctively thicker than other lists of the tubarium, and the thickest part starts at the level of th5 1. Remarks. G. velo n. sp. differs from Gothograptus obtectus in the development of veils. The veils of G. velo are built of a delicate reticulum with no thick transverse lists as in G. obtectus. Some of the veils are connected to the veil of the previous theca, forming an external layer above the thecal orifices and thecae (Fig. 9C).
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243. Gothograptus velo Koz��owska & Bates & Zalasiewicz & Radzevi��ius 2019, n. sp
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Koz��owska, Anna, Bates, Denis, Zalasiewicz, Jan, and Radzevi��ius, Sigitas
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Graptoloidea ,Hemichordata ,Gothograptus ,Animalia ,Retiolitidae ,Biodiversity ,Gothograptus velo ,Graptolithina ,Taxonomy - Abstract
Gothograptus velo n. sp. Fig. 22 1990. Gothograptus (Gothograptus) sp. A. Kozłowska-Dawidziuk, pp. 202���203, pl. 24: 2; fig. 6A���E. Type material. Mature tubarium, holotype ZPAL G.XIII/35, Zawada 1 core, depth 1533.3���1540 m, Poland, upper part of lundgreni Biozone. Material. One finite tubarium with nine pairs of thecae. Diagnosis. Proximal thecae with no genicular structures, successive medial and distal thecae have genicular veils. The veils are built of thin reticular lists; there are no thicker lists at the end of the veil as in G. obtectus. Reticulum below thecal lip undergoes reduction in distal thecae. Description. The mature tubarium has nine pairs of thecae. The distal end is slightly damaged, together with the appendix (Fig. 22). The tubarium length is 10.1 mm, together with the extending nema. The width of the tubarium at the level of the first pair of thecae is 0.8 mm. The widest part of the tubarium is 1.2 mm at the level of the fifth thecal pair. The tubarium tapers distally to a width of 0.6 mm at the level of the ninth pair of thecae. The sicula length is 1.5 mm; the prosicula apex is connected to the lateral wall of the tubarium at the level of the lip of th1 2. The thecal lips are thick whereas the genicular lists are thinner in distal thecae but well developed and easy to distinguish (Fig. 22B). The two first pairs of thecae do not have genicular structures. The first well-developed veil is on the fifth pair of thecae. Some reticular lists of the veil of th6 1 are connected to the geniculum of th5 1, and to the reticulum of the th5 1 veil (Figs 9C, 22B). The reticulum of the ventral thecal wall is well-developed up to the fifth pair of thecae, but distally, below the long veils, it become poorly developed, eventually disappearing under the veils of the last thecal pairs. The genicular and mid-ventral lists below the veils exhibit a similar decrease in thickness, becoming as thin as some lists of the veil (Figs 9C, 22B). The outer ancora is well-developed in the mature tubarium, and built of thick reticulum (Fig. 22D). Some membrane of the metasicular wall is connected to the virgella (Fig. 22C). Proximal internal structures typical of the genus Gothograptus are present, but they are difficult to distinguish in the flattened material to hand. The nema is distinctively thicker than other lists of the tubarium, and the thickest part starts at the level of th5 1. Remarks. G. velo n. sp. differs from Gothograptus obtectus in the development of veils. The veils of G. velo are built of a delicate reticulum with no thick transverse lists as in G. obtectus. Some of the veils are connected to the veil of the previous theca, forming an external layer above the thecal orifices and thecae (Fig. 9C)., Published as part of Koz��owska, Anna, Bates, Denis, Zalasiewicz, Jan & Radzevi��ius, Sigitas, 2019, Evolutionary significance of the retiolitine Gothograptus (Graptolithina) with four new species from the Silurian of the East European Platform (Baltica), Poland and Lithuania, pp. 435-469 in Zootaxa 4568 (3) on pages 462-466, DOI: 10.11646/zootaxa.4568.3.2, http://zenodo.org/record/2601607
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244. Gothograptus kozlowskii , Kozlowska-Dawidziuk 1990
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Kozłowska, Anna, Bates, Denis, Zalasiewicz, Jan, and Radzevičius, Sigitas
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Graptoloidea ,Hemichordata ,Gothograptus ,Gothograptus kozlowskii ,Animalia ,Retiolitidae ,Biodiversity ,Graptolithina ,Taxonomy - Abstract
Gothograptus kozlowskii Kozłowska-Dawidziuk, 1990 Figs 17���18 1990. Gothograptus (Gothograptus) kozlowskii, Kozłowska-Dawidziuk; pp. 197���200; pl. 23: 1���4; pl. 24: 3; fig. 4A���E. 2010. Gothograptus kozlowskii, Loydell, Nestor & M��nnik; p. 5, fig. 4h. Material. New material of G. kozlowskii comes from Poland, Bartoszyce IG-1 core, from the upper part of the lundgreni Biozone, depths from 1677.5 to 1672.8 m, and from the testis Biozone, depth 1668.8 m. These are mostly young and fragments of mature specimens, about 30 in all. Specimens from Lithuania, ��iupyliai-69 core, occur in the upper part of the lundgreni Biozone, depths: 1010.0 m to 1008.1 m. They represent mostly fragments of about 40 mature and young tubaria. Description. The best, completely preserved mature tubarium has fifteen thecae and a fragment of appendix. Tubarium without appendix is 6.5 mm long, 0.6 mm wide above the ancora umbrella rim. The widest part of the tubarium is at the level of the fourth thecal pair��� 0.8 mm; the width then decreases slowly towards the distal thecae and at the level of seventh thecal pair it is 0.5 mm. The virgella is very thin in mature specimens. The prosicular apex is located at the level of the lip of the second theca. The nema is thicker distally. In mature specimens the connecting rods, going from nema to lips, are poorly distinguishable from other lists of the lateral wall. The nassa type of genicular hoods of the first thecae are small, and do not cover the thecal orifices. The third pair of thecae has lateral spines with seams extending horizontally; the next thecae have hoods with a few lists of reticulum surrounded by a thick looping list. The structure extends below the lip with thicker lists bordering the structure. From the fourth thecal pair the genicular lists are very thin, and in the last thecae are difficult to define, whereas the lips are distinctive. As with the genicular lists, the mid-ventral lists become thinner distally; they are extremely thin in the three last pairs of thecae. In flattened mature specimens, only the genicular spines on proximal thecae distinctively protrude out of the tubarium (Fig. 17A, C���D). The most distal thecae have thick lips and very thin mid-ventral lists. The most mature specimen has extremely thick lists, the reticulum and clathrium being of similar widths, the widest about 50 ��m. In these specimens the thick outer ancora umbrella covers a large part of the ancora (Fig. 18C). Remarks. The new collections of Gothograptus kozlowskii from Lithuania and Poland come from the upper part of the lundgreni Biozone and from the testis Biozone. These data gave a more precise stratigraphical position of the species than the first described forms from an erratic boulder (Kozłowska-Dawidziuk 1990). Colonies of this species also occur in Latvia in the upper part of the lundgreni Biozone (Loydell et al. 2010). Radzevičius (2006, fig. 4G, H, I) illustrated juvenile Gothograptus specimens from the lundgreni Biozone of the ��iupyliai-69 borehole (Lithuania) and identified them as Gothograptus cf. kozlowskii. There are not enough features to identify them to the proper species., Published as part of Koz��owska, Anna, Bates, Denis, Zalasiewicz, Jan & Radzevi��ius, Sigitas, 2019, Evolutionary significance of the retiolitine Gothograptus (Graptolithina) with four new species from the Silurian of the East European Platform (Baltica), Poland and Lithuania, pp. 435-469 in Zootaxa 4568 (3) on page 457, DOI: 10.11646/zootaxa.4568.3.2, http://zenodo.org/record/2601607, {"references":["Kozlowska-Dawidziuk, A. (1990) The genus Gothograptus (Graptolithina) from the Wenlock of Poland. Acta Palaeontologica Polonica, 35, 191 - 209.","Loydell, D. K., Nestor, V. & Mannik, P. (2010) Integrated biostratigraphy of the lower Silurian of the Kolka- 54 core, Latvia. Geological Magazine, 147, 253 - 280.","Radzevicius, S. (2006) Late Wenlock biostratigraphy and the Pristiograptus virbalensis group (Graptolithina) in Lithuania and the Holy Cross Mountains. Geological Quarterly, 50, 333 - 344."]}
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245. Gothograptus domeyki Kozłowska & Bates & Zalasiewicz & Radzevičius 2019, n. sp
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Kozłowska, Anna, Bates, Denis, Zalasiewicz, Jan, and Radzevičius, Sigitas
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Graptoloidea ,Gothograptus domeyki ,Hemichordata ,Gothograptus ,Animalia ,Retiolitidae ,Biodiversity ,Graptolithina ,Taxonomy - Abstract
Gothograptus domeyki n. sp. Figs 15–16 ?1952 Gothograptus nassa, Bouček & Münch, pp. 11–15, fig. 2, a–i. Type material. Holotype number VU RET-13, mature specimen with seven pairs of thecae and appendix (Fig. 16 A–B), Šiupyliai-69 core, 1009,1 m, lundgreni Biozone, paratype number VU RET-14, finite tubarium (Fig. 16 C–E), Šiupyliai-69 core, depth 1010.0 m, lundgreni Biozone, Lithuania. Etymology. Ignacy Domeyko (1802–1889) was a Polish geologist, mineralogist and educator; most of his life was spent in Chile. Diagnosis. Gothograptus with genicular hoods of nassa type developed on the first pair of thecae; second pair of thecae may have paired spines with seams or remnants of reticulum between them; subsequent thecae lacking genicular processes except for the last theca with a reticulated hood. Distinctively thicker thecal lips than pleural and genicular lists. G othograptus domeyki differs from other Gothograptus species in the lack of genicular structures in the medial and distal thecae. Remarks. Gothograptus domeyki n. sp. differs from other Gothograptus species in the lack of any genicular processes in most thecae as well as in having thick lips. G. domeyki n. sp. is similar to G. kozlowskii in having nassa type hoods on the first pair of thecae and reticulated hoods on the last pair of thecae. Similar reticulated hoods on the last thecae are also found in G. storchi. G. domeyki n. sp. is so far known only from Lithuania. Bouček & Münch (1952) described some retiolitines as Gothograptus nassa, from the Czech Republic, lundgreni Biozone. Their drawings show some tubaria with thick lips, and without genicular nassa hoods, similar to those described herein for the first time in G. domeyki n. sp. Proper recognition of this form needs some detailed study. Material. Two cores from Lithuania: Šiupyliai-69 core, depths: 1009.7 m 30 young, 12 mature; 1009.1 m 50 young, 31 mature; Vilkaviškis-131 core, depth 1095.8 m four fragments of mature specimens. Upper part of lundgreni Biozone. Description. Mature tubaria usually have seven or eight pairs of thecae and appendix. The total length of the tubarium is about 7.0 mm, together with the appendix. The tubarium is almost parallel-sided, widest at 0.83 mm at the level of the first thecal pair, and then it slowly narrows to 0.4 mm just below the appendix. In some mature specimens the prongs of the ancora, as well as the sicular rim and lists above the proximal lateral orifices, are extremely thick ((Fig. 16A, B, E, H, I). An outer ancora is well developed in mature specimens. The proximal ventral orifices are overgrown by reticulum in mature colonies. Mid-ventral lists are 0.5 mm long in the first and last thecae, the rest are about 0.7 mm long. Genicular structures start to develop when the colony reaches about five thecal pairs. There are three types of genicular structures in mature tubaria of G. domeyki n. sp. The first pair of thecae have nassa hoods; usually they are small and do not cover the orifices of thecae or they are slightly larger than the thecal orifice. The second and third thecal pairs have a pair of curved spines grown on the pleural lists, extending horizontally. Seams on the inner sides of the spines indicate that there was a thin membrane between them, so that the spines form the sides of a hood. The bases of the spines in the mature tubaria are of triangular shape (Fig. 16G). Similar spines forming hoods are also found in Gothograptus kozlowskii (see below). The next thecae have no hoods; their lips are thick, about twice as thick as the geniculum list. The genicular lists became significantly thinner in the last thecae. The last pair of thecae have reticulated hoods covering orifices; the genicular list is not developed. The reticulum of these hoods is connected with the appendix (Fig. 16A). umbrella, outside view. Some young tubaria with five pairs of thecae have reticulum up to the third pair of thecae, small nassa hoods on the first thecae, the two next pairs of thecae having thin genicular spines. A specimen with seven pairs of thecae has a well-developed reticulum, except on the two last thecae. The lists of young colonies are thin; the thickest is the nema (Fig. 15A, D). During astogeny the next thicker lists are the lateral apertural rods. The lips and genicular lists are so thick that the thecal orifice is very narrow (Fig. 15E, 16E). The thecal orifices vary in shape from nearly rectangular to pyramidal with rounded corners (Fig. 7A, 16C, E). Mature colonies have a dense reticulum of similar thickness to the clathrial lists, thus the structures formed by clathrial lists are difficult to distinguish.
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246. Gothograptus auriculatus Koz��owska & Bates & Zalasiewicz & Radzevi��ius 2019, n. sp
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Koz��owska, Anna, Bates, Denis, Zalasiewicz, Jan, and Radzevi��ius, Sigitas
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Graptoloidea ,Hemichordata ,Gothograptus ,Animalia ,Retiolitidae ,Biodiversity ,Gothograptus auriculatus ,Graptolithina ,Taxonomy - Abstract
Gothograptus auriculatus n. sp. Figs 13���14 2006 Gothograptus nassa, Calner, Kozłowska, Masiak & Schmitz, p. 80, fig. 1E. Type material. Holotype ZPAL G.55/23, mature specimen with six pairs of thecae and distal end broken off (Fig. 13 B); paratype ZPAL G.55/24, distal end of mature tubarium with five pairs of thecae and appendix (Fig. 13 C, F). Bartoszyce IG-1well, depth 1645.2 m, Poland, lower part of praedeubeli Biozone. Etymology. Latin auriculatus ���relating to the earlobe shape of the genicular structures. Diagnosis. Tubarium with genicular structures formed by the nassa type of hood, and paired vertical auriclelike structures bordering both sides of the thecal orifices. Auricle structures are characteristic only of Gothograptus auriculatus n. sp. In mature colonies the auricles bend towards the mid-ventral list below the thecal lip and nassa hood. Remarks. G. auriculatus n. sp. differs from G. nassa in having two lateral auricles, as additional elements located on the lateral sides of the thecal orifices and below the lips. Young colonies of the new species have nassa hoods; the auricles appear later in astogeny. Material. The material studied comes from Poland, Lithuania and Germany. The most abundant material comes from the Bartoszyce IG- well, ranges from 1649.0 to 1645.2 m, praedeubeli Biozone, yielding about 1300, mostly young, specimens. Two fragments of G. auriculatus come from Lithuania, Pilviskiai-141 core, depth 842.2 m, nassa / praedeubeli Biozone. Description. Tubaria slightly widening up to th1 2, then parallel-sided and gently tapering distally, ended by an appendix. Most of the specimens are represented by fragments of tubaria up to the 11th thecal pair. Tubarium width at the level of the first thecal pair is about 1.5 mm, and in the middle part of the tubarium 1.2 mm. The longest fragment of tubarium, comprising 11 pairs of thecae, is 10 mm long. The lists of the young stages of colony are very thin, about 15 ��m across, while the lists of the mature tubarium are about five times thicker, at 75 ��m. The thickening of lists starts from the proximal end. The looping meshes of the ancora umbrella are overgrown by a reticulum in the mature colonies. The ancora prongs below the lateral proximal orifices and the lists surrounding the proximal lateral orifices are extremely wide in mature specimens (Fig. 14 C���F).The reticular lists also become very wide in mature colonies, making the reticulum meshes very small. In the most mature specimens the reticulum lists reach similar thicknesses to those of the main lists of the tubaria (Fig. 13D). Based on well-preserved specimens representing the young tubaria, the sicula length is estimated at 1.4 mm, the length of the prosicula at 400 ��m (Fig. 2). The nema starts at the level of the th1 2 geniculum and is connected to the obverse lateral wall of the tubarium. The typical genicular structures are well developed in mature specimens. During astogeny the auricles, typical of this species, are first developed in more distal thecae (Fig. 13 A���C). The longest hoods in mature specimens are about 370 ��m long, and extend below the lips. As a consequence the thecal orifices are not visible. The hoods of astogenetically old tubaria may be elongated in the centre of their lower parts (Fig. 13E). The distal thecae are shorter and their genicular structures are usually irregular and shorter horizontally (Fig. 13E). In mature specimens, the nema widens distally to about 67 ��m across at the most distal end of the tubarium and in the appendix (Figs 3, 13C). A nematularium was not identified. Remarks. Gothograptus auriculatus n. sp. has been described from the praedeubeli Biozone of Sweden, and published as G. nassa (Calner et al. 2006, fig. 1E). This taxon, also found in erratic boulders from Germany, has been illustrated and identified by Jaeger as Gothograptus nassa late form (Maletz 2010, figs 1, 2). The specimens, stored in the Museum f��r Naturkunde, Berlin, come from a fauna containing the type material of Colonograptus praedeubeli., Published as part of Koz��owska, Anna, Bates, Denis, Zalasiewicz, Jan & Radzevi��ius, Sigitas, 2019, Evolutionary significance of the retiolitine Gothograptus (Graptolithina) with four new species from the Silurian of the East European Platform (Baltica), Poland and Lithuania, pp. 435-469 in Zootaxa 4568 (3) on pages 451-454, DOI: 10.11646/zootaxa.4568.3.2, http://zenodo.org/record/2601607, {"references":["Calner, M., Kozlowska, A., Masiak, M. & Schmitz, B. (2006) A shoreline to deep basin correlation chart for the middle Silurian coupled extinction-stable isotopic event. GFF, 128, 79 - 84. https: // doi. org / 10.1080 / 11035890601282079","Maletz, J. (2010) Retiolitid graptolites from the collection of Hermann Jaeger II: Cometograptus, Spinograptus and Plectograptus. Palaontologische Zeitschrift, 84, 501 - 522. https: // doi. org / 10.1007 / s 12542 - 010 - 0065 - x"]}
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247. Artificial Radionuclide Fallout Signals
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Waters, Colin N, Irka, Hajdas, Zalasiewicz, Jan, Jeandel, Catherine, University of Leicester, Physics Department (ETHZ), and Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)
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[SDU] Sciences of the Universe [physics] ,[SDU]Sciences of the Universe [physics] ,[SDU.STU] Sciences of the Universe [physics]/Earth Sciences ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
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- 2019
248. A formal Anthropocene is compatible with but distinct from its diachronous anthropogenic counterparts
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Zalasiewicz, Jan, Waters, Colin N., Head, Martin J, Poirier, Clement, Summerhayes, Colin, Leinfelder, Reinhold, Grinevald, Jacques, Steffen, Will, Syvitski, James P., Haff, Peter K., McNeill, John R., Wagreich, Michael, Fairchild, Ian J., Richter, Daniel DeB., Vidas, Davor, Williams, Mark, Barnosky, Anthony D., and Cearreta, Alejandro
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Antroposen ,Anthropocene - Abstract
We analyse the ‘three flaws’ to potentially defining a formal Anthropocene geological time unit as advanced by Ruddiman (2018). (1) We recognize a long record of pre-industrial human impacts, but note that these increased in relative magnitude slowly and were strongly time-transgressive by comparison with the extraordinarily rapid, novel and near-globally synchronous changes of post-industrial time. (2) The rules of stratigraphic nomenclature do not ‘reject’ pre-industrial anthropogenic signals – these have long been a key characteristic and distinguishing feature of the Holocene. (3) In contrast to the contention that classical chronostratigraphy is now widely ignored by scientists, it remains vital and widely used in unambiguously defining geological time units and is an indispensable part of the Earth sciences. A mounting body of evidence indicates that the Anthropocene, considered as a precisely defined geological time unit that begins in the mid-20th century, is sharply distinct from the Holocene.
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249. A Lower Palaeozoic shallow water sequence in the eastern European Variscides (SW Poland): provenance and depositional history
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Kryza, Ryszard, Turniak, Krzysztof, Muszyński, Andrzej, and Zalasiewicz, Jan A.
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- 1994
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250. Can nuclear weapons fallout mark the beginning of the Anthropocene Epoch?
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Waters, Colin N., Syvitski, James P. M., Gałuszka, Agnieszka, Hancock, Gary J., Zalasiewicz, Jan, Cearreta, Alejandro, Grinevald, Jacques, Jeandel, Catherine, McNeill, J. R., Summerhayes, Colin, and Barnosky, Anthony
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SCIENTISTS ,HUMANITY ,ANTHROPOCENE Epoch ,NUCLEAR explosions ,NUCLEAR weapons - Abstract
Many scientists are making the case that humanity is living in a new geological epoch, the Anthropocene, but there is no agreement yet as to when this epoch began. The start might be defined by a historical event, such as the beginning of the fossil-fueled Industrial Revolution or the first nuclear explosion in 1945. Standard stratigraphic practice, however, requires a more significant, globally widespread, and abrupt signature, and the fallout from nuclear weapons testing appears most suitable. The appearance of plutonium 239 (used in post-1945 above-ground nuclear weapons tests) makes a good marker: This isotope is rare in nature but a significant component of fallout. It has other features to recommend it as a stable marker in layers of sedimentary rock and soil, including: long half-life, low solubility, and high particle reactivity. It may be used in conjunction with other radioactive isotopes, such as americium 241 and carbon 14, to categorize distinct fallout signatures in sediments and ice caps. On a global scale, the first appearance of plutonium 239 in sedimentary sequences corresponds to the early 1950s. While plutonium is easily detectable over the entire Earth using modern measurement techniques, a site to define the Anthropocene (known as a “golden spike”) would ideally be located between 30 and 60 degrees north of the equator, where fallout is maximal, within undisturbed marine or lake environments. [ABSTRACT FROM PUBLISHER]
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- 2015
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