Abstract.-Vase-shaped microfossils (VSMs) occur in dolomitic extraclasts of indeterminate provenance within the basal diamictite of the Neoproterozoic Urucum Formation (Jacadigo Group) of west-central Brazil, having an age constrained between 889 ± 44 Ma (K-Ar; basement rocks) and 587 ± 7 Ma ( 40 Ar/ 39

Vase-shaped microfossils (VSMs) occur in dolostone clasts within conglomerates, breccias, and diamictites of the Neoproterozoic Urucum Formation, Jacadigo Group, southwest Brazil. Although their taphonomic history is distinct from those of other VSM assemblages, morphometric comparison of Urucum fossils with five others described previously from North America and Europe show that two of the Urucum species—the long-necked Limeta lageniformis Morais, Fairchild, and Lahr in Morais et al., 2017 and the funnel-necked Palaeoamphora urucumense Morais et al., 2017—occur in the Kwagunt and Callison Lake assemblages, as does Pakupaku kabin Riedman, Porter, and Calver, 2017 recently described from the Togari Group, Tasmania. Obelix rootsii (Cohen, Irvine, and Strauss, 2017) new combination, previously known only from the Callison Lake Formation, is documented here from the Kwagunt Formation. In addition, Trigonocyrillium horodyskii (Bloeser, 1985) and Bonniea dacruchares Porter, Meisterfeld, and Knoll, 2003, first described from the Kwagunt assemblage, have now been found in the Urucum Formation. In light of this survey, 16 of the 18 validly described VSM species are now known to occur in the Kwagunt Formation and 13 in the Callison Lake Formation, with 12 of them shared by both formations. The fact that the Urucum VSM assemblage exhibits six of seven species in common with the Kwagunt Formation—L. lageniformis, P. urucumense, Cycliocyrillium simplex Porter, Meisterfeld, and Knoll, 2003, C. torquata Porter, Meisterfeld, and Knoll, 2003, B. dacruchares Porter, Meisterfeld, and Knoll, 2003, and T. horodyskii (Bloeser, 1985)—and all but the last of these in common with the Callison Lake Formation supports correlation of these three assemblages and indicates that the source of the fossiliferous clasts within the Urucum Formation may well have been a now-vanished late Tonian carbonate platform.UUID: http://zoobank.org/ac0becd6-29ff-4491-80fa-0291730fba65

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Feathers are the most complex and diversified integuments in vertebrates. Their complexity are provided by the different forms and functions, and they occur both in nonavian and avian-dinosaurs. Despite their rareness, feathers are found throughout the world, and the Santana Formation (comprised by Crato and Romualdo formations) of the Araripe Basin is responsible for the majority of these records in Brazil. Most occurrences is consisted by isolated feathers, where downy-feathers is the recurrent morphotype, two coelurosaurs and one enantiornithe bird. The sedimentary deposition of this unit is consisted by a lacustrine (Crato Fm) and lagoonal (Romualdo Fm) environments, where reducing conditions prevailed, precluding the activity of bottom dwelling organisms that favored the exquisite preservation. Despite the arid and hot conditions during the Cretaceous, life teemed in the adjacency of both paleolakes, however, feathered non-avian dinosaurs were not found yet in the Crato Member. By the great diversity of life that existed in the paleolake surroundings, is possible to recognize, through the fossil record, that a complex and diversified trophic chain was well established during the time period of sedimentation of this unit. When the remains reached the bottom of the paleolakes, the subsequent isolation from the environment allowed their preservation. In this work, three fossilized feathers, consisted of two downy and one contour feather, extracted from the laminated limestone of the Crato Member of the Santana Formation, were described and identified according to morphological and evolutionary models. We also used the terminology commonly applied to extant organisms. Relying on the fossil record of this unit and the adjacencies formations and basins (by autochthonous condition), taxonomic inferences can be made when the lowest hierarchy level is considered, and hence, is possible to propose the plausible taxa that could bear these elements. Taphonomic and paleoecological aspects, such as the preservation of these structures, and the presence of dinosaurs, were also reviewed, as well as the future perspectives about the study of these elements. Despite the virtual low significance, the pragmatical study of fossilized feathers, can help with the understanding of the evolution and paleobiology of dinosaurs, especially on the South Hemisphere. ABSTRACTFeathers are the most complex and diversified integuments in vertebrates. Their complexity are provided by the different forms and functions, and they occur both in non-avian and avian-dinosaurs. Despite their rareness, feathers are found throughout the world, and the Santana Formation (comprised by Crato and Romualdo formations) of the Araripe Basin is responsible for the majority of these records in Brazil. Most occurrences is consisted by isolated feathers, where downy-feathers is the recurrent morphotype, two coelurosaurs and one enantiornithe bird. The sedimentary deposition of this unit is consisted by a lacustrine (Crato Fm) and lagoonal (Romualdo Fm) environ...