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Basso-Alves JP, Ribeiro CC, Teixeira SP. Floral Development of Rhamnaceae and Origin of Its Unique Floral Features. PLANTS (BASEL, SWITZERLAND) 2023; 12:247. [PMID: 36678960 PMCID: PMC9861707 DOI: 10.3390/plants12020247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 12/27/2022] [Accepted: 12/28/2022] [Indexed: 06/17/2023]
Abstract
Rhamnaceae flowers have a peculiar morphology, including keeled sepals, one stamen whorl closely related to the petals, and a broad perigynous hypanthium that supports a voluminous nectary. In the present investigation, we detailed the flower development of five Rhamnaceae species to understand the origin of such specific floral characteristics. Floral buds and flowers were processed for surface and histological analyses. The sepals emerge in sequential order and the other organs in simultaneous order. The development of the perigynous hypanthium renders the floral apex broad and concave. The sepals undergo abaxial thickening early on, forming a keel and strongly influencing the floral merosity. Petals and stamens appear close to each other on the same radius in a very short plastochron. The carpels unite soon after their emergence, forming a syncarpous ovary and free style branches. Differences in intercalary carpel growth promote the formation of inferior (Gouania virgata) and semi-inferior ovaries (Colubrina glandulosa, Hovenia dulcis, and Sarcomphalus joazeiro). Rhamnidium elaeocarpum does not undergo such growth, and the resulting ovary is superior. The keeled sepals promote the isolation of the petal-stamen pair inside the flower bud. The possibility of a common primordium that the originates petal and stamen is refuted. Comparisons with other Rosales families provide insights into the floral origin and diversification of Rhamnaceae.
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Affiliation(s)
- João Paulo Basso-Alves
- Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Diretoria de Pesquisa Científica, Rua Pacheco Leão, 915, Rio de Janeiro 22460-030, RJ, Brazil
| | - Carimi Cortez Ribeiro
- Post-Graduate Program in Comparative Biology, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, SP, Brazil
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-903, SP, Brazil
| | - Simone Pádua Teixeira
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-903, SP, Brazil
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Wilf P, Zou X, Donovan MP, Kocsis L, Briguglio A, Shaw D, Slik JWF, Lambiase JJ. First fossil-leaf floras from Brunei Darussalam show dipterocarp dominance in Borneo by the Pliocene. PeerJ 2022; 10:e12949. [PMID: 35356469 PMCID: PMC8958975 DOI: 10.7717/peerj.12949] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Accepted: 01/26/2022] [Indexed: 01/11/2023] Open
Abstract
The Malay Archipelago is one of the most biodiverse regions on Earth, but it suffers high extinction risks due to severe anthropogenic pressures. Paleobotanical knowledge provides baselines for the conservation of living analogs and improved understanding of vegetation, biogeography, and paleoenvironments through time. The Malesian bioregion is well studied palynologically, but there have been very few investigations of Cenozoic paleobotany (plant macrofossils) in a century or more. We report the first paleobotanical survey of Brunei Darussalam, a sultanate on the north coast of Borneo that still preserves the majority of its extraordinarily diverse, old-growth tropical rainforests. We discovered abundant compression floras dominated by angiosperm leaves at two sites of probable Pliocene age: Berakas Beach, in the Liang Formation, and Kampong Lugu, in an undescribed stratigraphic unit. Both sites also yielded rich palynofloral assemblages from the macrofossil-bearing beds, indicating lowland fern-dominated swamp (Berakas Beach) and mangrove swamp (Kampong Lugu) depositional environments. Fern spores from at least nine families dominate both palynological assemblages, along with abundant fungal and freshwater algal remains, rare marine microplankton, at least four mangrove genera, and a diverse rainforest tree and liana contribution (at least 19 families) with scarce pollen of Dipterocarpaceae, today's dominant regional life form. Compressed leaves and rare reproductive material represent influx to the depocenters from the adjacent coastal rainforests. Although only about 40% of specimens preserve informative details, we can distinguish 23 leaf and two reproductive morphotypes among the two sites. Dipterocarps are by far the most abundant group in both compression assemblages, providing rare, localized evidence for dipterocarp-dominated lowland rainforests in the Malay Archipelago before the Pleistocene. The dipterocarp fossils include winged Shorea fruits, at least two species of plicate Dipterocarpus leaves, and very common Dryobalanops leaves. We attribute additional leaf taxa to Rhamnaceae (Ziziphus), Melastomataceae, and Araceae (Rhaphidophora), all rare or new fossil records for the region. The dipterocarp leaf dominance contrasts sharply with the family's <1% representation in the palynofloras from the same strata. This result directly demonstrates that dipterocarp pollen is prone to strong taphonomic filtering and underscores the importance of macrofossils for quantifying the timing of the dipterocarps' rise to dominance in the region. Our work shows that complex coastal rainforests dominated by dipterocarps, adjacent to swamps and mangroves and otherwise similar to modern ecosystems, have existed in Borneo for at least 4-5 million years. Our findings add historical impetus for the conservation of these gravely imperiled and extremely biodiverse ecosystems.
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Affiliation(s)
- Peter Wilf
- Department of Geosciences and Earth & Environmental Systems Institute, Pennsylvania State University, University Park, Pennsylvania, United States
| | - Xiaoyu Zou
- Department of Geosciences and Earth & Environmental Systems Institute, Pennsylvania State University, University Park, Pennsylvania, United States
| | - Michael P. Donovan
- Department of Geosciences and Earth & Environmental Systems Institute, Pennsylvania State University, University Park, Pennsylvania, United States,Department of Paleobotany and Paleoecology, Cleveland Museum of Natural History, Cleveland, Ohio, United States
| | - László Kocsis
- Faculty of Science, Universiti Brunei Darussalam, Gadong, Brunei Darussalam,Institute of Earth Surface Dynamics, Faculty of Geosciences and Environment, University of Lausanne, Lausanne, Switzerland
| | - Antonino Briguglio
- Dipartimento di Scienze della Terra, dell’Ambiente e della Vita, Università degli Studi di Genova, Genoa, Italy
| | - David Shaw
- Biostratigraphic Associates (UK) Ltd., Stoke-on-Trent, UK
| | - JW Ferry Slik
- Faculty of Science, Universiti Brunei Darussalam, Gadong, Brunei Darussalam
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Jud NA, Gandolfo MA. Fossil evidence from South America for the diversification of Cunoniaceae by the earliest Palaeocene. ANNALS OF BOTANY 2021; 127:305-315. [PMID: 32860407 PMCID: PMC7872129 DOI: 10.1093/aob/mcaa154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/27/2020] [Indexed: 06/01/2023]
Abstract
BACKGROUND AND AIMS Cunoniaceae are woody plants with a distribution that suggests a complex history of Gondwanan vicariance, long-distance dispersal, diversification and extinction. Only four out of ~27 genera in Cunoniaceae are native to South America today, but the discovery of extinct species from Argentine Patagonia is providing new information about the history of this family in South America. METHODS We describe fossil flowers collected from early Danian (early Palaeocene, ~64 Mya) deposits of the Salamanca Formation. We compare them with similar flowers from extant and extinct species using published literature and herbarium specimens. We used simultaneous analysis of morphology and available chloroplast DNA sequences (trnL-F, rbcL, matK, trnH-psbA) to determine the probable relationship of these fossils to living Cunoniaceae and the co-occurring fossil species Lacinipetalum spectabilum. KEY RESULTS Cunoniantha bicarpellata gen. et sp. nov. is the second species of Cunoniaceae to be recognized among the flowers preserved in the Salamanca Formation. Cunoniantha flowers are pentamerous and complete, the anthers contain in situ pollen, and the gynoecium is bicarpellate and syncarpous with two free styles. Phylogenetic analysis indicates that Cunoniantha belongs to crown-group Cunoniaceae among the core Cunoniaceae clade, although it does not have obvious affinity with any tribe. Lacinipetalum spectabilum, also from the Salamanca Formation, belongs to the Cunoniaceae crown group as well, but close to tribe Schizomerieae. CONCLUSIONS Our findings highlight the importance of West Gondwana in the evolution of Cunoniaceae during the early Palaeogene. The co-occurrence of C. bicarpellata and L. spectabilum, belonging to different clades within Cunoniaceae, indicates that the diversification of crown-group Cunoniaceae was under way by 64 Mya.
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Affiliation(s)
- Nathan A Jud
- Department of Biology, William Jewell College, Liberty, MO, USA
| | - Maria A Gandolfo
- L. H. Bailey Hortorium, Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA
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Wilf P, Wing SL, Meyer HW, Rose JA, Saha R, Serre T, Cúneo NR, Donovan MP, Erwin DM, Gandolfo MA, González-Akre E, Herrera F, Hu S, Iglesias A, Johnson KR, Karim TS, Zou X. An image dataset of cleared, x-rayed, and fossil leaves vetted to plant family for human and machine learning. PHYTOKEYS 2021; 187:93-128. [PMID: 35068970 PMCID: PMC8702526 DOI: 10.3897/phytokeys.187.72350] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 12/05/2021] [Indexed: 05/04/2023]
Abstract
Leaves are the most abundant and visible plant organ, both in the modern world and the fossil record. Identifying foliage to the correct plant family based on leaf architecture is a fundamental botanical skill that is also critical for isolated fossil leaves, which often, especially in the Cenozoic, represent extinct genera and species from extant families. Resources focused on leaf identification are remarkably scarce; however, the situation has improved due to the recent proliferation of digitized herbarium material, live-plant identification applications, and online collections of cleared and fossil leaf images. Nevertheless, the need remains for a specialized image dataset for comparative leaf architecture. We address this gap by assembling an open-access database of 30,252 images of vouchered leaf specimens vetted to family level, primarily of angiosperms, including 26,176 images of cleared and x-rayed leaves representing 354 families and 4,076 of fossil leaves from 48 families. The images maintain original resolution, have user-friendly filenames, and are vetted using APG and modern paleobotanical standards. The cleared and x-rayed leaves include the Jack A. Wolfe and Leo J. Hickey contributions to the National Cleared Leaf Collection and a collection of high-resolution scanned x-ray negatives, housed in the Division of Paleobotany, Department of Paleobiology, Smithsonian National Museum of Natural History, Washington D.C.; and the Daniel I. Axelrod Cleared Leaf Collection, housed at the University of California Museum of Paleontology, Berkeley. The fossil images include a sampling of Late Cretaceous to Eocene paleobotanical sites from the Western Hemisphere held at numerous institutions, especially from Florissant Fossil Beds National Monument (late Eocene, Colorado), as well as several other localities from the Late Cretaceous to Eocene of the Western USA and the early Paleogene of Colombia and southern Argentina. The dataset facilitates new research and education opportunities in paleobotany, comparative leaf architecture, systematics, and machine learning.
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Affiliation(s)
- Peter Wilf
- Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA 16802, USAPennsylvania State UniversityUniversity ParkUnited States of America
| | - Scott L. Wing
- Department of Paleobiology, Smithsonian Institution, Washington, DC 20013, USADepartment of Paleobiology, Smithsonian InstitutionWashington, DCUnited States of America
| | - Herbert W. Meyer
- Florissant Fossil Beds National Monument, National Park Service, Florissant, CO 80816, USAFlorissant Fossil Beds National Monument, National Park ServiceFlorissantUnited States of America
| | - Jacob A. Rose
- School of Engineering, Brown University, Providence, RI 02912, USABrown UniversityProvidenceUnited States of America
| | - Rohit Saha
- Department of Cognitive, Linguistic and Psychological Sciences, Carney Institute for Brain Science, Brown University, Providence, RI 02912, USAMuseo Paleontológico E. FeruglioTrelewArgentina
| | - Thomas Serre
- Department of Cognitive, Linguistic and Psychological Sciences, Carney Institute for Brain Science, Brown University, Providence, RI 02912, USAMuseo Paleontológico E. FeruglioTrelewArgentina
| | - N. Rubén Cúneo
- CONICET-Museo Paleontológico Egidio Feruglio, Trelew 9100, Chubut, Argentinaepartment of Paleobotany and Paleoecology, Cleveland Museum of Natural HistoryClevelandUnited States of America
| | - Michael P. Donovan
- Department of Paleobotany and Paleoecology, Cleveland Museum of Natural History, Cleveland, OH 44106, USAUniversity of California-BerkeleyBerkeleyUnited States of America
| | - Diane M. Erwin
- University of California-Berkeley, Museum of Paleontology, Berkeley, CA 94720, USACornell UniversityIthacaUnited States of America
| | - María A. Gandolfo
- LH Bailey Hortorium, Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USASmithsonian Conservation Biology Institute, National Zoological Park,Front RoyalUnited States of America
| | - Erika González-Akre
- Conservation Ecology Center, Smithsonian Conservation Biology Institute, National Zoological Park, Front Royal, VA, 22630, USANegaunee Integrative Research Center, Field Museum of Natural HistoryChicagoUnited States of America
| | - Fabiany Herrera
- Negaunee Integrative Research Center, Field Museum of Natural History, Chicago, IL, 60605, USAYale UniversityNew HavenUnited States of America
| | - Shusheng Hu
- Division of Paleobotany, Peabody Museum of Natural History, Yale University, New Haven, CT 06520, USAInstituto de Investigaciones en Biodiversidad y Ambiente INIBIOMA, CONICET-UNComaSan Carlos de BarilocheArgentina
| | - Ari Iglesias
- Instituto de Investigaciones en Biodiversidad y Ambiente INIBIOMA, CONICET-UNComa, San Carlos de Bariloche 8400, Río Negro, ArgentinaDepartment of Paleobiology, Smithsonian InstitutionWashingtonUnited States of America
| | - Kirk R. Johnson
- Department of Paleobiology, Smithsonian Institution, Washington, DC 20013, USADepartment of Paleobiology, Smithsonian InstitutionWashington, DCUnited States of America
| | - Talia S. Karim
- University of Colorado Museum of Natural History, Boulder, CO 80503, USAUniversity of Colorado Museum of Natural HistoryBoulderUnited States of America
| | - Xiaoyu Zou
- Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA 16802, USAPennsylvania State UniversityUniversity ParkUnited States of America
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Zamaloa MC, Gandolfo MA, Nixon KC. 52 million years old Eucalyptus flower sheds more than pollen grains. AMERICAN JOURNAL OF BOTANY 2020; 107:1763-1771. [PMID: 33274448 PMCID: PMC7839439 DOI: 10.1002/ajb2.1569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 08/25/2020] [Indexed: 06/12/2023]
Abstract
PREMISE Fossils provide fundamental evidence of the evolutionary processes that crafted today's biodiversity and consequently for understanding life on Earth. We report the finding of Myrtaceidites eucalyptoides pollen grains preserved within the anthers of a 52-million-year-old Eucalyptus flower collected at Laguna del Hunco locality of Argentinean Patagonia and discuss its implications in understanding the evolutionary history of the iconic Australian genus Eucalyptus. METHODS Pollen grains were extracted from the flower's anthers and were then observed under light microscopy and scanning electron microscopy. The phylogenetic position of the fossil was investigated by adding pollen data to a previously published total-evidence matrix and analyzing it using parsimony. RESULTS We erect the species Eucalyptus xoshemium for the fossil flower. Pollen extracted from E. xoshemium belongs to the species Myrtaceidites eucalyptoides, which, until now, was only known as dispersed pollen. The numerous pollen grains recovered from the single flower allowed estimation of M. eucalyptoides' variability. Results of the phylogenetic analysis reinforce the position of this fossil within crown group Eucalyptus. CONCLUSIONS The discovery of these pollen grains within a Patagonian Eucalyptus fossil flower confirms the hypothesis that Myrtaceidites eucalyptoides represents fossil pollen in the Eucalyptus lineage, extends the geographic and stratigraphic fossil pollen record, and supports an earlier age for crown-group eucalypts.
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Affiliation(s)
- Maria C. Zamaloa
- Museo Paleontológico Egidio FeruglioAvda. Fontana 140Trelew, Chubut9100Argentina
| | - Maria A. Gandolfo
- LH Bailey HortoriumPlant Biology SectionSchool of Integrative Plant ScienceCornell UniversityIthacaNY14853USA
| | - Kevin C. Nixon
- LH Bailey HortoriumPlant Biology SectionSchool of Integrative Plant ScienceCornell UniversityIthacaNY14853USA
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van Santen M, Linder HP. The assembly of the Cape flora is consistent with an edaphic rather than climatic filter. Mol Phylogenet Evol 2020; 142:106645. [DOI: 10.1016/j.ympev.2019.106645] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 10/07/2019] [Accepted: 10/08/2019] [Indexed: 12/14/2022]
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Zhang Q, Onstein RE, Little SA, Sauquet H. Estimating divergence times and ancestral breeding systems in Ficus and Moraceae. ANNALS OF BOTANY 2019; 123:191-204. [PMID: 30202847 PMCID: PMC6344110 DOI: 10.1093/aob/mcy159] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 08/06/2018] [Indexed: 05/30/2023]
Abstract
Background and Aims Although dioecy, which characterizes only 6 % of angiosperm species, has been considered an evolutionary dead end, recent studies have demonstrated that this is not necessarily the case. Moraceae (40 genera, 1100 spp., including Ficus, 750 spp.) are particularly diverse in breeding systems (including monoecy, gynodioecy, androdioecy and dioecy) and thus represent a model clade to study macroevolution of dioecy. Methods Ancestral breeding systems of Ficus and Moraceae were inferred. To do so, a new dated phylogenetic tree of Ficus and Moraceae was first reconstructed by combining a revised 12-fossil calibration set and a densely sampled molecular data set of eight markers and 320 species. Breeding system evolution was then reconstructed using both parsimony and model-based (maximum likelihood and Bayesian) approaches with this new time scale. Key Results The crown group ages of Ficus and Moraceae were estimated in the Eocene (40.6-55.9 Ma) and Late Cretaceous (73.2-84.7 Ma), respectively. Strong support was found for ancestral dioecy in Moraceae. Although the ancestral state of Ficus remained particularly sensitive to model selection, the results show that monoecy and gynodioecy evolved from dioecy in Moraceae, and suggest that gynodioecy probably evolved from monoecy in Ficus. Conclusions Dioecy was found not to be an evolutionary dead end in Moraceae. This study provides a new time scale for the phylogeny and a new framework of breeding system evolution in Ficus and Moraceae.
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Affiliation(s)
- Qian Zhang
- Laboratoire Ecologie Systématique Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Orsay, France
| | - Renske E Onstein
- Laboratoire Ecologie Systématique Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Orsay, France
- German Centre for Integrative Biodiversity Research (iDiv), Halle‐Jena‐Leipzig, Leipzig, Germany
| | - Stefan A Little
- Laboratoire Ecologie Systématique Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Orsay, France
| | - Hervé Sauquet
- Laboratoire Ecologie Systématique Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Orsay, France
- National Herbarium of New South Wales (NSW), Royal Botanic Gardens and Domain Trust, Sydney, Australia
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Jud NA, Gandolfo MA, Iglesias A, Wilf P. Fossil flowers from the early Palaeocene of Patagonia, Argentina, with affinity to Schizomerieae (Cunoniaceae). ANNALS OF BOTANY 2018; 121:431-442. [PMID: 29309506 PMCID: PMC5838809 DOI: 10.1093/aob/mcx173] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 11/09/2017] [Indexed: 06/01/2023]
Abstract
Background and Aims Early Palaeocene (Danian) plant fossils from Patagonia provide information on the recovery from the end-Cretaceous extinction and Cenozoic floristic change in South America. Actinomorphic flowers with eight to ten perianth parts are described and evaluated in a phylogenetic framework. The goal of this study is to determine the identity of these fossil flowers and to discuss their evolutionary, palaeoecological and biogeographical significance. Methods More than 100 fossilized flowers were collected from three localities in the Danian Salamanca and Peñas Coloradas Formations in southern Chubut. They were prepared, photographed and compared with similar extant and fossil flowers using published literature and herbarium specimens. Phylogenetic analysis was performed using morphological and molecular data. Key results The fossil flowers share some but not all the synapomorphies that characterize the Schizomerieae, a tribe within Cunoniaceae. These features include the shallow floral cup, variable number of perianth parts arranged in two whorls, laciniate petals, anthers with a connective extension, and a superior ovary with free styles. The number of perianth parts is doubled and the in situ pollen is tricolporate, with a surface more like that of other Cunoniaceae outside Schizomerieae, such as Davidsonia or Weinmannia. Conclusions An extinct genus of crown-group Cunoniaceae is recognized and placed along the stem lineage leading to Schizomerieae. Extant relatives are typical of tropical to southern-temperate rainforests, and these fossils likely indicate a similarly warm and wet temperate palaeoclimate. The oldest reliable occurrences of the family are fossil pollen and wood from the Upper Cretaceous of the Antarctica and Argentina, whereas in Australia the family first occurs in upper Palaeocene deposits. This discovery demonstrates that the family survived the Cretaceous-Palaeogene boundary event in Patagonia and that diversification of extant lineages in the family was under way by the earliest Cenozoic.
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Affiliation(s)
- Nathan A Jud
- L. H. Bailey Hortorium, Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA
| | - Maria A Gandolfo
- L. H. Bailey Hortorium, Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA
| | - Ari Iglesias
- Universidad Nacional del Comahue, Instituto de Investigaciones en Biodiversidad y Ambiente INIBIOMA-CONICET, San Carlos de Bariloche, Rio Negro, Argentina
| | - Peter Wilf
- Department of Geosciences, Pennsylvania State University, University Park, PA, USA
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