Three flora assemblages of Yima formation, in western Henan are systematically studied. The beginning time from which the climate in this region during the middle Jurassic and the late Jurassic period getting hot was ...Three flora assemblages of Yima formation, in western Henan are systematically studied. The beginning time from which the climate in this region during the middle Jurassic and the late Jurassic period getting hot was Bajocian to early Bathonian,obviously earlier than in south Europe, middle Asia,and Siberia.展开更多
The thiolliericrinids(Thiolliericrinidae) are comatulids(Comatulida),which retained their stalks as adults.Here,we report a centrodorsal from the Bajocian strata(Middle Jurassic) of the Djebel Kérdacha area,north...The thiolliericrinids(Thiolliericrinidae) are comatulids(Comatulida),which retained their stalks as adults.Here,we report a centrodorsal from the Bajocian strata(Middle Jurassic) of the Djebel Kérdacha area,northwestern Algeria(Africa).It is the first thiolliericrinid report from outside of Europe and also the oldest representative of the Thiolliericrinidae whose first occurrence is from the Oxfordian.The crinoid is assigned to Copernicrinus zamorae gen.et sp.nov.The reported new taxon shows strong similarities with the stemless ‘true’comatulids,Solanocrinites;the only difference is the presence of a facet to the stem in Copernicrinus.The closest comparable thiolliericrinid to Copernicrinus is the Oxfordian Thiolliericrinus,interpreted as a descendant of the latter.The origin and overview of all thiolliericrinid representatives are also discussed herein.展开更多
The Middle Jurassic palynomorphs from the Yan'an Formation in Dongsheng region of Nei Monggol, consist of 63 species of fossil spores and pollen grains belonging to 34 genera, of which two species were described a...The Middle Jurassic palynomorphs from the Yan'an Formation in Dongsheng region of Nei Monggol, consist of 63 species of fossil spores and pollen grains belonging to 34 genera, of which two species were described as new. Based on statistical analysis of 3 863 specimens identified in 10 samples from Hantaichuan, Nianpanlianggou and Liugou sections, the sporo-pollen assemblage from the Yan'an Formation in Dongsheng region was established, which is generally characterized by the slight dominance of gymnospermous pollen grains (generally attaining proportion of 51%-54%), whereas the pteridophytic spores reach 46%-49% in abundance. In comparison with those of adjacent regions as well as Eurasia and North America, the present sporo-pollen assemblage is regarded to early Middle Jurassic (corresponding to Bajocian Stage) in geological age. According to the climatic conditions reflected by the palynoflora, the paleoclimate in Dongsheng region is suggested to be warm temperate or subtropical warm and humid during the early Middle Jurassic.展开更多
文摘Three flora assemblages of Yima formation, in western Henan are systematically studied. The beginning time from which the climate in this region during the middle Jurassic and the late Jurassic period getting hot was Bajocian to early Bathonian,obviously earlier than in south Europe, middle Asia,and Siberia.
基金supported by the ‘Male Projekty Badawcze 2022’(Faculty of Natural Sciences,University of Silesia in Katowice) to Mariusz A. Salamonfinancially supported by the statutory activities of the Institute of Botany,Faculty of Biology,Jagiellonian University in Krakow(N18/DBS/000002) to Bartosz J. PlachnoAGH-UST Grant No. 16.16.140.315 to Marcin Krajewski。
文摘The thiolliericrinids(Thiolliericrinidae) are comatulids(Comatulida),which retained their stalks as adults.Here,we report a centrodorsal from the Bajocian strata(Middle Jurassic) of the Djebel Kérdacha area,northwestern Algeria(Africa).It is the first thiolliericrinid report from outside of Europe and also the oldest representative of the Thiolliericrinidae whose first occurrence is from the Oxfordian.The crinoid is assigned to Copernicrinus zamorae gen.et sp.nov.The reported new taxon shows strong similarities with the stemless ‘true’comatulids,Solanocrinites;the only difference is the presence of a facet to the stem in Copernicrinus.The closest comparable thiolliericrinid to Copernicrinus is the Oxfordian Thiolliericrinus,interpreted as a descendant of the latter.The origin and overview of all thiolliericrinid representatives are also discussed herein.
文摘The Middle Jurassic palynomorphs from the Yan'an Formation in Dongsheng region of Nei Monggol, consist of 63 species of fossil spores and pollen grains belonging to 34 genera, of which two species were described as new. Based on statistical analysis of 3 863 specimens identified in 10 samples from Hantaichuan, Nianpanlianggou and Liugou sections, the sporo-pollen assemblage from the Yan'an Formation in Dongsheng region was established, which is generally characterized by the slight dominance of gymnospermous pollen grains (generally attaining proportion of 51%-54%), whereas the pteridophytic spores reach 46%-49% in abundance. In comparison with those of adjacent regions as well as Eurasia and North America, the present sporo-pollen assemblage is regarded to early Middle Jurassic (corresponding to Bajocian Stage) in geological age. According to the climatic conditions reflected by the palynoflora, the paleoclimate in Dongsheng region is suggested to be warm temperate or subtropical warm and humid during the early Middle Jurassic.