Climate and geological change as drivers of Mauritiinae palm biogeography Giovanni Bogotá‐Ángel, Huasheng Huang, Phillip E. Jardine, Nicolas Chazot, Sonia Salamanca, Hannah Banks, Andres Pardo‐Trujillo, Angelo Plata, Hernando Dueñas, Wim Star, Rob Langelaan, Ali Eisawi, Obianuju P. Umeji, Lucky O. Enuenwemba, Shalini Parmar, Rosemery Rocha Silveira, Jun Ying Lim, Vandana Prasad, Robert J. Morley, Christine D. Bacon, Carina Hoorn Journal of Biogeography, 2021 ABSTRACT Aim Forest composition and distribution are determined by a myriad of factors, including climate. As models of tropical rain forest, palms are often used as indicator taxa, particularly the Mauritiinae. We question, what characterizes the Mauritiinae pollen in the global fossil record? And when did the Mauritiinae become endemic to South America? Location Global tropics. Taxon Mauritiinae palms (Arecaceae: Lepidocaryeae). Methods Pollen trait data from extinct and extant Mauritiinae pollen were generated from light‐, scanning‐, and transmission electron microscopy. Statistical morphometric analysis was used to define species and their relationships to other Mauritiinae. We also compiled a comprehensive pollen database for extinct and extant Mauritiinae and mapped their global geographical distribution from Late Cretaceous to present, using GBIF and fossil data. Results Our morphometric analysis identified 18 species (11 extinct and seven extant), all exhibiting exine indentations, a synapomorphy of the subtribe. The fossil taxa and early divergent extant Lepidocaryum are all monosulcate, whereas the extant Mauritia and Mauritiella species are all monoulcerate. Paleobiogeographical maps of fossil Mauritiinae pollen occurrences suggest the taxon originated in equatorial Africa during the Cretaceous, and expanded their range to South America, and to India in the Paleocene. Range retraction started in the early Eocene with extirpation from India, and reduction in diversity in Africa culminating at the Eocene–Oligocene Transition (EOT). In contrast, in South America, the distribution is maintained, and since the Neogene Mauritiinae palms are mostly restricted to swampy, lowland habitats. Main conclusions Morphometric analysis shows that since their origin Mauritiinae pollen are relatively species poor, and Mauritiidites resembles Lepidocaryum . We also conclude that the biogeographical history of the Mauriitinae and, by extension, tropical forests was strongly affected by global climatic cooling events. In particular, the climate change at the EOT was a fundamental determinant of current tropical forest distribution.
Age and palaeoenvironments of the Manacapuru Formation, Presidente Figueiredo (AM) region, Lochkovian of the Amazonas Basin Patrícia Ferreira Rocha, Rosemery Rocha da Silveira, Roberto Cesar de Mendonça Barbosa Brazilian Journal of Geology, 2019 The Manacapuru Formation, Amazonas Basin, outcrops on the margins of a highway in the region of Presidente Figueiredo, state of Amazonas. A systematic palynological and a lithofaciological analysis was carried out aiming to contribute to the paleoenvironmental understanding of the Manacapuru Formation and its respective age. The present work uses the analysis of the chitinozoan for biostratigraphic purposes as a tool. A total of 27 samples were collected in which an assemblage of lower Lochkovian can be recognized, whose characteristic species are Angochitina filosa, Cingulochitina ervensis, Lagenochitina navicula, and Pterochitina megavelata. It was possible to identify an intense reworking in the exposure, evidenced by the presence of paleofaunas ranging from Ludfordian to Pridolian, which may be associated to the constant storm events that reached the shelf. The lithofaciological analysis allowed the recognition of 6 predominantly muddy sedimentary lithofacies with sandy intercalations that suggest deposition in an offshore region inserted in a shallow marine shelf and influenced by storms.
Palynology (fungi and fern spores, gimnosperm pollen grains, algae cysts and scolecodont) from the solimões and içá formations (neogene and pleistocene, solimões basin), Amazonas, Brazil Rosemery Rocha da SILVEIRA, Paulo A. SOUZA Pesquisas Em Geociencias, 2016 O conhecimento palinológico dos depósitos das formações cenozoicas da Bacia do Solimões tem sido substancialmente aprimorado nas últimas décadas, a partir de materiais de subsuperfície, bem como de afloramentos. Este trabalho apresenta parte dos resultados taxonômicos do estudo de 93 amostras oriundas de 12 afloramentos das formações Solimões e Içá, na região de Coari (cinco afloramentos), e Alto Solimões (sete afloramentos), estado do Amazonas, Brasil, que revelaram conjuntos palinológicos abundantes, diversificados e bem preservados. Aqui são listadas e ilustradas 53 espécies de palinomorfos, compreendendo 11 espécies de esporos de fungos, 31 de esporos de pteridófitas e dois de grãos de pólen de gimnospermas, oito de algas (sete clorofíceas e uma dinofícea), e um de escolecodonte, com descrições quando necessário. A composição palinológica é distinta para as duas áreas analisadas, tendo na região do Alto Solimões documentação de formas como Crassoretitriletes vanraadshooveni, Foveotriletes ornatos, Magnastriatites grandiosus e a ocorrência de um cisto de dinoflagelado. Na região de Coari foi verificado predomínio de esporomorfos, com grande diversidade e abundância de esporos de fungo e pteridófitas.
Palynology (Angiosperm pollen grains) from solimões and içá formations (solimões basin), in coari and alto SolimõEs Regions, Amazonas Rosemery Rocha da Silveira, Paulo Alves de Souza Revista Brasileira De Paleontologia, 2015 SOLIMES BASIN), IN COARI AND ALTO SOLIMES REGIONS, AMAZONAS. A total of 93 samples collected at 12 outcrops from Solimes and I formations, in the region of Coari (fi ve outcrops) and Alto Solimes (seven outcrops), Amazonas State, was conducted for pollen analysis. Palynomorphs recovered comprise sporomorphs (representatives of fungi, ferns, gymnosperms and angiosperms), algae cysts and scolecodont. In general, the specimens are well preserved, rarely presenting corrosion or breaking, resulting in an exceptional photomicrographic record. This paper presents the 48 angiosperm pollen grains, appropriately illustrated and described, when needed. The composition of palynofl oras in both areas presents contrasts; those ones from Alto Solimes show less diversity, but have higher abundance in comparison with the Coari ones. In the Alto Solimes the most common taxa are Crotoidaepollenites reticulatus, Grimsdalea magnaclavata, Monoporites annulatus, Multimarginites vanderhammeni, Retitrescolpites irregularis, Perfotricolpites digitatus, Corsinipollenites undulatus, Bombacacidites nacimientoensis, B. simpliciriloensis and Perisyncolporites pokornyi. The most common taxa in Coari are Fenestrites sp.2, Mauritiidites franciscoi, Monoporites annulatus, Retitrescolpites irreguaris, Corsinipollenites undulatus and Bombacacidites nacimientoensis. Recognition of Asteraceae indicates for deposits of the Solimes Formation, in the region of Coari, Late Miocene-Pliocene age; and to the Ia Formation, Pleistocene age, based on the presence of Alnipollenites verus. The presence of Grimsdalea magnaclava indicates Middle Miocene age for the region Alto Solimes. The biostratigraphy signifi cance is preliminary discussed based on the recognition of certain guide species. Comparisons are performed taking into account coeval records in the basin.
Neogene-Quaternary sedimentary and paleovegetation history of the eastern Solimões Basin, central Amazon region Afonso César Rodrigues Nogueira, Rosemery Silveira, José Tasso Felix Guimarães Journal of South American Earth Sciences, 2013 Palynological and stratigraphical analyses were carried out on the outcrops of the Solimoes River to present new information about freshwater paleoenvironments of a fluvial–deltaic and meandering river system, evaluate the vegetation changes in the upper Solimoes and Ica Formations in the eastern Solimoes Basin, and the role of the Purus Arc in the evolution of central Amazon during the upper Neogene. The upper Miocene to Pliocene Solimoes Formation is related to a fluvial–deltaic system, with fine-grained sediments of the prodelta–lacustrine environment supplied by meandering distributaries and delta front environment. The lake and distributaries were surrounded by extensive deltaic and floodplains colonized by lowland freshwater forests under wet climate conditions, persisting until the Pliocene. The Ica Formation started to deposit unconformably on the Solimoes Formation during the Pleistocene, following the development of extensive meandering channels surrounded by floodplains of an essentially fluvial system linked to development of the present eastward direction of the Amazon River until the Atlantic coast. These floodplains were colonized by few palm species and pteridophytes of lowland freshwater forests during the Pleistocene. Additionally, no algae and fungi were observed, which may be related to drier climate conditions and/or different morphological conditions than the upper Solimoes Formation.
Fossil fungi from miocene sedimentary rocks of the central and coastal Amazon Region, North Brazil José Tasso Felix Guimarães, Afonso César Rodrigues Nogueira, José Bandeira Cavalcante Da Silva, Joelson Lima Soares, Rosemery Silveira Journal of Paleontology, 2013 Samples from outcrops of the Miocene Solimões and Barreiras formations from the central and coastal Amazon regions of Brazil were analyzed palynologically. Assemblages of fossil fungi were identified, and are described herein, and their relevance to paleoenvironmental and paleoclimatic studies in tropical regions discussed. The fungal assemblage comprises four spore groups, 19 species belonging to 12 genera. Additionally, two new species are proposed. The samples from the Solimões Formation contain the following taxa: Mediaverrunites elsikii, Mediaverrunites mulleri, Monoporisporites sp., Fusiformisporites crabbii, and Multicellites cingulatus. The presence of these suggests river channel margins colonized by freshwater vegetation, where seasonal fluctuations of water table and rainfall produce wetter substrates. The samples from the Barreiras Formation showed higher species and generic diversity than those from the Solimões Formation with Hypoxylonites minutus, Hypoxylonsporites ater, Hypoxylonites sp., the new species Inapertisporites multiporus n. sp., Pluricellaesporites regularis, Lacrimasporonites levis, Monoporisporites annulatus, Spirotremesporites simplex, Dyadosporites novus, Dyadosporites sp., and Multicellaesporites attenuates. All of these correspond to parasitic fungi from a range of from tropical wetlands. Spegazzinites sp. and Dicellaesporites aculeolatus, good indicators of marine influence and mangrove presence, were also identified in the samples from the Barreiras Formation. Furthermore, the fungal spore taxa Inapertisporites multiporus, Mediaverrunites elsikii, Mediaverrunites mulleri, Pluricellaesporites regularis, and Spirotremesporites simplex serve as stratigraphic indicators when combined with miospore index taxa such as Crassoretitriletes vanraadshooveni, Grimsdalea magnaclavata and Fenestrites longispinosus indicating a Miocene age for these sediments in the Amazon region.
