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Purgina C, Ulrich S, Weber M, Grímsson F. Morphological and Ultrastructural Features of Selected Epidendroideae Pollen Dispersal Units and New Insights into Their Chemical Nature. Plants (Basel) 2024; 13:1114. [PMID: 38674523 PMCID: PMC11053828 DOI: 10.3390/plants13081114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 04/05/2024] [Accepted: 04/08/2024] [Indexed: 04/28/2024]
Abstract
Orchidaceae display enormous diversity in their flower morphology, which is particularly evident in their pollen dispersal units (pollinia, pollinaria). The packaging of pollen by elastoviscin leads to a great diversity of these morphologically and structurally complex pollen units. Despite being one of the most diverse angiosperm families, the available palynological data on orchids remain limited and sometimes contradicting. This study provides new insights into the pollen morphology and ultrastructure of five orchid species from the subfamily Epidendroideae, using combined light, scanning electron, and transmission electron microscopy. The aim was to compare the morphology and ultrastructure of pollen dispersal units and to elucidate the chemical nature of the pollen wall layers and of elastoviscin. Our combined light and electron microscopy investigation demonstrated the presence of six tetrad types even within a single pollinium, which is unique for orchids. The application of different staining methods confirmed the assumed lipidic nature of elastoviscin and the differences in its contrast and ultrastructure suggest a mixture of sticky materials with dissimilar chemical compositions. This study affirmed that sporopollenin is mostly restricted to the outer pollen grains of peripheral tetrads in compact and sectile pollinia, while inner tetrads exhibit highly reduced non-sporopollenin pollen walls.
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Affiliation(s)
- Carola Purgina
- Department of Botany and Biodiversity Research, Division of Structural and Functional Botany, University of Vienna, 1030 Vienna, Austria; (S.U.); (M.W.)
| | - Silvia Ulrich
- Department of Botany and Biodiversity Research, Division of Structural and Functional Botany, University of Vienna, 1030 Vienna, Austria; (S.U.); (M.W.)
- Department of Historical Archaeology, Austrian Archaeological Institute (OeAI), Austrian Academy of Sciences (OeAW), 1010 Vienna, Austria
| | - Martina Weber
- Department of Botany and Biodiversity Research, Division of Structural and Functional Botany, University of Vienna, 1030 Vienna, Austria; (S.U.); (M.W.)
| | - Friðgeir Grímsson
- Department of Botany and Biodiversity Research, Division of Structural and Functional Botany, University of Vienna, 1030 Vienna, Austria; (S.U.); (M.W.)
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Ulrich S, Vieira M, Coiro M, Bouchal JM, Geier C, Jacobs BF, Currano ED, Lenz OK, Wilde V, Zetter R, Grímsson F. Origin and Early Evolution of Hydrocharitaceae and the Ancestral Role of Stratiotes. Plants (Basel) 2024; 13:1008. [PMID: 38611537 PMCID: PMC11013807 DOI: 10.3390/plants13071008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 03/27/2024] [Accepted: 03/29/2024] [Indexed: 04/14/2024]
Abstract
The combined morphological features of Stratiotes (Hydrocharitaceae) pollen, observed with light and electron microscopy, make it unique among all angiosperm pollen types and easy to identify. Unfortunately, the plant is (and most likely was) insect-pollinated and produces relatively few pollen grains per flower, contributing to its apparent absence in the paleopalynological record. Here, we present fossil Stratiotes pollen from the Eocene of Germany (Europe) and Kenya (Africa), representing the first reliable pre-Pleistocene pollen records of this genus worldwide and the only fossils of this family discovered so far in Africa. The fossil Stratiotes pollen grains are described and compared to pollen from a single modern species, Stratiotes aloides L. The paleophytogeographic significance and paleoecological aspects of these findings are discussed in relation to the Hydrocharitaceae fossil records and molecular phylogeny, as well as the present-day distribution patterns of its modern genera.
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Affiliation(s)
- Silvia Ulrich
- Department of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria; (S.U.); (J.M.B.); (C.G.); (R.Z.)
- Department of Historical Archaeology, Austrian Archaeological Institute (OeAI), Austrian Academy of Sciences (OeAW), 1010 Vienna, Austria
| | - Manuel Vieira
- Department of Earth Sciences, GeoBioTec, NOVA School of Science and Technology, Campus de Caparica, 2829-516 Caparica, Portugal;
| | - Mario Coiro
- Department of Palaeontology, University of Vienna, 1090 Vienna, Austria
| | - Johannes M. Bouchal
- Department of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria; (S.U.); (J.M.B.); (C.G.); (R.Z.)
| | - Christian Geier
- Department of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria; (S.U.); (J.M.B.); (C.G.); (R.Z.)
| | - Bonnie F. Jacobs
- Roy M. Huffington Department of Earth Sciences, Southern Methodist University, Dallas, TX 75275, USA;
| | - Ellen D. Currano
- Departments of Botany and Geology & Geophysics, University of Wyoming, Laramie, WY 82071, USA;
| | - Olaf K. Lenz
- Institute of Applied Geosciences, Technical University Darmstadt, 64287 Darmstadt, Germany;
| | - Volker Wilde
- Section Palaeobotany, Division Palaeontology and Historical Geology, Senckenberg Research Institute and Natural History Museum Frankfurt, 60325 Frankfurt am Main, Germany;
| | - Reinhard Zetter
- Department of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria; (S.U.); (J.M.B.); (C.G.); (R.Z.)
| | - Friðgeir Grímsson
- Department of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria; (S.U.); (J.M.B.); (C.G.); (R.Z.)
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Pan AD, Jacobs BF, Bush RT, de la Estrella M, Grímsson F, Herendeen PS, van der Burgt XM, Currano ED. First evidence of a monodominant (Englerodendron, Amherstieae, Detarioideae, Leguminosae) tropical moist forest from the early Miocene (21.73 Ma) of Ethiopia. PLoS One 2023; 18:e0279491. [PMID: 36630378 PMCID: PMC9833558 DOI: 10.1371/journal.pone.0279491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 11/16/2022] [Indexed: 01/12/2023] Open
Abstract
Many tropical wet forests are species-rich and have relatively even species frequency distributions. But, dominance by a single canopy species can also occur in tropical wet climates and can remain stable for centuries. These are uncommon globally, with the African wet tropics supporting more such communities than the Neotropics or Southeast Asia. Differences in regional evolutionary histories are implied by biogeography: most of Africa's monodominance-forming species are Amherstieae-tribe legumes; monodominance in Neotropical forests occur among diverse taxonomic groups, often legumes, but rarely Amherstieae, and monodominance in Southeast Asian forests occurs mostly among Dipterocarpaceae species. African monodominant forests have been characterized ecologically and taxonomically, but their deep-time history is unknown despite their significant presence and bottom-up ecological influence on diversity. Herein we describe fossil leaflets of Englerodendron mulugetanum sp. nov., an extinct species of the extant genus Englerodendron (Berlinia Clade, Amherstieae, Detarioideae) from the 21.73 Ma Mush Valley site in Ethiopia. We also document a detailed study of associated legume pollen, which originate from a single taxon sharing characters with more than one extant descendant. Taxonomically, the pollen is most comparable to that from some extant Englerodendron species and supports a likely affiliation with the Englerodendron macrofossils. The Mush Valley site provides the first fossil evidence of a monodominant tropical forest in Africa as represented by leaflets and pollen. Previous studies documented >2400 leaves and leaflets from localities at six stratigraphic levels spanning 50,000-60,000 years of nearly continuous deposition within seven meters of section; all but the basal level contain ≥ 50% E. mulugetanum leaflets. Modern leaf litter studies in African mixed vs. monodominant forests indicates the likelihood of monodominance in the forests that surrounded the Mush paleolake, particularly after the basal level. Thus, we provide an early case for monodominance within the Amherstieae legumes in Africa.
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Affiliation(s)
- Aaron D. Pan
- Museum of Texas Tech University, Texas Tech University, Lubbock, Texas, United States of America
- Botanical Research Institute of Texas, Fort Worth, Texas, United States of America
| | - Bonnie F. Jacobs
- Roy M. Huffington Department of Earth Sciences, Southern Methodist University, Dallas, Texas, United States of America
| | - Rosemary T. Bush
- Department of Earth and Planetary Sciences, Northwestern University, Evanston, Illinois, United States of America
| | - Manuel de la Estrella
- Departamento de Botánica, Ecología y Fisiología Vegetal, Celestino Mutis, Campus de Rabanales, Universidad de Córdoba, Córdoba, Spain
| | - Friðgeir Grímsson
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | - Patrick S. Herendeen
- Division of Plant Science and Conservation, Chicago Botanic Garden, Glencoe, Illinois, United States of America
| | | | - Ellen D. Currano
- Department of Botany and Geology and Geophysics, University of Wyoming, Laramie, Wyoming, United States of America
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Bao T, Wedmann S, Grímsson F, Beutel RG, Seyfullah L, Bao L, Jarzembowski EA. Was the kateretid beetle Pelretes really a Cretaceous angiosperm pollinator? Nat Plants 2022; 8:38-40. [PMID: 34949805 DOI: 10.1038/s41477-021-01044-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 11/09/2021] [Indexed: 06/14/2023]
Affiliation(s)
- Tong Bao
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-sen University, Guangzhou, China.
| | - Sonja Wedmann
- Senckenberg Forschungsstation Grube Messel, Senckenberg Forschungsinstitut und Naturmuseum Frankfurt/M, Messel, Germany
| | - Friðgeir Grímsson
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | - Rolf Georg Beutel
- Institut für Zoologie und Evolutionsforschung, Friedrich-Schiller-Universität Jena, Jena, Germany
| | - Leyla Seyfullah
- Department of Palaeontology, University of Vienna, Vienna, Austria
| | - Liang Bao
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-sen University, Guangzhou, China
| | - Edmund A Jarzembowski
- State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing, China
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Grímsson F, Ulrich S, Zetter R, Hörnschemeyer T, Engel MS, Wedmann S. How to extract and analyze pollen from internal organs and exoskeletons of fossil insects? STAR Protoc 2021; 2:100923. [PMID: 34761235 PMCID: PMC8567441 DOI: 10.1016/j.xpro.2021.100923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
This protocol explains how to extract pollen from fossil insects with subsequent descriptions of pollen treatment. We also describe how to document morphological and ultrastructural features with light-microscopy and electron microscopy. It enables a taxonomic assignment of pollen that can be used to interpret flower-insect interactions, foraging and feeding behavior of insects, and the paleoenvironment. The protocol is limited by the state of the fossil, the presence/absence of pollen on fossil specimens, and the availability of extant pollen for comparison. For complete details on the use and execution of this protocol, please refer to Wappler et al. (2015), Ulrich and Grímsson (2020), and Wedmann et al. (2021). Protocol for extracting and analyzing pollen grains from fossil insects Individual fossil grains can be analyzed using a combined approach Simple and fast TEM embedding and sectioning protocol Protocol enables a taxonomic assignment of pollen
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Affiliation(s)
- Friðgeir Grímsson
- Department of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria
| | - Silvia Ulrich
- Department of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria
| | - Reinhard Zetter
- Department of Paleontology, University of Vienna, 1090 Vienna, Austria
| | - Thomas Hörnschemeyer
- Johann-Friedrich-Blumenbach-Institut für Zoologie & Anthropologie, Georg-August-Universität Göttingen, 37073 Göttingen, Germany
| | - Michael S Engel
- Division of Entomology, Natural History Museum, and Department of Ecology & Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA
| | - Sonja Wedmann
- Senckenberg Forschungsstation Grube Messel, Senckenberg Forschungsinstitut und Naturmuseum Frankfurt/M., 64409 Messel, Germany
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Wedmann S, Hörnschemeyer T, Engel MS, Zetter R, Grímsson F. The last meal of an Eocene pollen-feeding fly. Curr Biol 2021; 31:2020-2026.e4. [PMID: 33705719 DOI: 10.1016/j.cub.2021.02.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/26/2020] [Accepted: 02/10/2021] [Indexed: 11/17/2022]
Abstract
One of the most important trophic interactions today is that between insects and their floral hosts. This biotic association is believed to have been critical to the radiation of flowering plants and many pollinating insect lineages over the last 120 million years (Ma). Trophic interactions among fossil organisms are challenging to study, and most inferences are based on indirect evidence. Fossil records providing direct evidence for pollen feeding, i.e., fossil stomach and gut contents, are exceptionally rare.1,2 Such records have the potential to provide information on aspects of animal behavior and ecology as well as plant-animal interactions that are sometimes not yet recognized for their extant relatives. The dietary preferences of short-proboscid nemestrinids are unknown, and pollinivory has not been recorded for extant Nemestrinidae.3 We analyzed the contents of the conspicuously swollen abdomen of an ca. 47.5 Ma old nemestrinid fly of the genus Hirmoneura from Messel, Germany, with photogrammetry and state-of-the-art palynological methods. The fly fed on pollen from at least four plant families-Lythraceae, Vitaceae, Sapotaceae, and Oleaceae-and presumably pollinated flowers of two extant genera, Decodon and Parthenocissus. We interpret the feeding and foraging behavior of the fly, reconstruct its preferred habitat, and conclude about its pollination role and importance in paratropical environments. This represents the first evidence that short-proboscid nemestrinid flies fed, and possibly feed to this day, on pollen, demonstrating how fossils can provide vital information on the behavior of insects and their ecological relationships with plants.
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Affiliation(s)
- Sonja Wedmann
- Senckenberg Forschungsstation Grube Messel, Senckenberg Forschungsinstitut und Naturmuseum Frankfurt/M., 64409 Messel, Germany.
| | - Thomas Hörnschemeyer
- Johann-Friedrich-Blumenbach-Institut für Zoologie & Anthropologie, Georg-August-Universität Göttingen, 37073 Göttingen, Germany
| | - Michael S Engel
- Division of Entomology, Natural History Museum, and Department of Ecology & Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA
| | - Reinhard Zetter
- Department of Paleontology, University of Vienna, 1090 Vienna, Austria
| | - Friðgeir Grímsson
- Department of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria.
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Grímsson F, Ulrich S, Coiro M, Graham SA, Jacobs BF, Currano ED, Xafis A, Zetter R. Hagenia from the early Miocene of Ethiopia: Evidence for possible niche evolution? Ecol Evol 2021; 11:5164-5186. [PMID: 34025999 PMCID: PMC8131786 DOI: 10.1002/ece3.7408] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/10/2021] [Accepted: 02/22/2021] [Indexed: 11/21/2022] Open
Abstract
Fossil pollen believed to be related to extant Hagenia abyssinica were discovered in the early Miocene (21.73 Ma) Mush Valley paleoflora, Ethiopia, Africa. Both the fossil and extant pollen grains of H. abyssinica were examined with combined light microscopy, scanning electron microscopy, and transmission electron microscopy to compare the pollen and establish their relationships. Based on this, the fossil pollen grains were attributed to Hagenia. The presence of Hagenia in the fossil assemblage raises the questions if its habitat has changed over time, and if the plants are/were wind pollinated. To shed light on these questions, the morphology of extant anthers was also studied, revealing specialized hairs inside the anthers, believed to aid in insect pollination. Pollen and anther morphology are discussed in relation to the age and origin of the genus within a molecular dated phylogenetic framework, the establishment of complex topography in East Africa, other evidence regarding pollination modes, and the palynological record. The evidence presented herein, and compiled from the literature, suggests that Hagenia was an insect-pollinated lowland rainforest element during the early Miocene of the Mush Valley. The current Afromontane habitat and ambophilous (insect and wind) pollination must have evolved in post-mid-Miocene times.
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Affiliation(s)
- Friðgeir Grímsson
- Department of Botany and Biodiversity ResearchUniversity of ViennaViennaAustria
| | - Silvia Ulrich
- Department of Botany and Biodiversity ResearchUniversity of ViennaViennaAustria
| | - Mario Coiro
- Department of Systematic and Evolutionary BotanyUniversity of ZurichZurichSwitzerland
| | | | - Bonnie F. Jacobs
- Roy M. Huffington Department of Earth SciencesSouthern Methodist UniversityDallasTXUSA
| | - Ellen D. Currano
- Departments of Botany and Geology & GeophysicsUniversity of WyomingLaramieWYUSA
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Xafis A, Mayda S, Alçiçek MC, Kaya T, Halaçlar K, Grímsson F, Nagel D. Large giraffids (Mammalia, Ruminantia) from the new late Miocene fossiliferous locality of Kemiklitepe-E (Western Anatolia, Turkey). Paleobiodivers Paleoenviron 2020; 101:853-867. [PMID: 34721707 PMCID: PMC8550776 DOI: 10.1007/s12549-020-00433-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 02/14/2020] [Accepted: 04/29/2020] [Indexed: 06/13/2023]
Abstract
Kemiklitepe is a well-known locality with four recognised fossiliferous horizons, KTA to KTD, which have yielded a plethora of mammalian remains. Previous taxonomic studies indicate the presence of three giraffid taxa: Samotherium major and Palaeotragus rouenii from the uppermost three horizons, KTA, KTB and KTC, as well as Palaeotragus rouenii and Samotherium? sp. from the lowermost KTD horizon. In this study a new locality, Kemiklitepe-E, is presented for the first time. Kemiklitepe-E is located approximately 350 m NW of the classic Kemiklitepe locality. The fossiliferous sedimentary rocks at Kemiklitepe-E occur at the same stratigraphic level as localities KTA, KTB and KTC. The preliminary faunal list includes representatives of Proboscidea, Chalicotheriidae, Equidae, Bovidae and Giraffidae. Comprehensive descriptions and comparisons of the Kemiklitepe-E Giraffidae specimens suggest the co-occurrence of two large giraffids: Samotherium major and Helladotherium duvernoyi. Samotherium major, previously documented from this region, is the most common taxon at Kemiklitepe. Helladotherium duvernoyi is rare at Kemiklitepe and here reported for the first time. The two taxa coexisted during the middle Turolian in Greece and Western Anatolia. In addition, it is suggested that specimens of Samotherium? sp described from KTD possibly belong to Samotherium neumayri. Based on the stratigraphic position of fossiliferous rocks, as well as the faunal data presented herein, the newly discovered locality is considered to be of middle Turolian (MN12) age.
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Affiliation(s)
- Alexandros Xafis
- Department of Palaeontology, Faculty of Earth Sciences, University of Vienna, 1090 Vienna, Austria
| | - Serdar Mayda
- Department of Biology, Faculty of Science, Ege University, 35100 Izmir, Turkey
| | | | - Tanju Kaya
- Natural History Museum, Ege University, 35100 Izmir, Turkey
| | - Kazım Halaçlar
- Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, 100044 China
| | - Friðgeir Grímsson
- Department of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria
| | - Doris Nagel
- Department of Palaeontology, Faculty of Earth Sciences, University of Vienna, 1090 Vienna, Austria
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Xafis A, Saarinen J, Bastl K, Nagel D, Grímsson F. Palaeodietary traits of large mammals from the middle Miocene of Gračanica (Bugojno Basin, Bosnia-Herzegovina). Paleobiodivers Paleoenviron 2020; 100:457-477. [PMID: 32647552 PMCID: PMC7320953 DOI: 10.1007/s12549-020-00435-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 05/04/2020] [Accepted: 05/09/2020] [Indexed: 06/11/2023]
Abstract
Recent excavations at the Gračanica coal mine (Bugojno Basin, Bosnia-Herzegovina) have unearthed numerous skeletal parts of fossil vertebrates, including a noteworthy collection of mammalian remains. Previous palaeoecological investigations of the Dinarides Lake System were established using stratigraphical, palaeofloral, and malacological data. However, large mammal remains have so far not been used to reconstruct the terrestrial palaeoenvironment of this important fossil ecosystem. Here, the palaeodietary preferences of large mammals were investigated, using a multiproxy approach by employing dental microwear and dental mesowear analysis, in order to provide new perspectives on the terrestrial palaeoecology of the Dinarides Lake System. The dental microwear of all available adult mammalian teeth was analysed. Dental mesowear analysis was employed for ungulate and proboscidean taxa, using mesowear scores and mesowear angles, respectively. The analysis reveals the presence of browsing, "dirty browsing", and mixed-feeding herbivorous taxa, with seasonal fruit, or even grass intake. Additionally, the analysis of the carnivores suggests the presence of hyaena- and cheetah-like hypercarnivores, as well as generalists. The palaeodietary traits of the fossil mammals suggest a closed canopy-like environment, which is supported by the fossil plant assemblage. Palaeopalynological data confirm the omnipresence of fleshy fruit-bearing plants, herbaceous taxa, as well as grasses, which justifies the seasonal fruit browsing, the common "dirty browsing", and the occasional grazing behaviour visualized for some of the fossil mammals from Gračanica.
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Affiliation(s)
- Alexandros Xafis
- Department of Palaeontology, Faculty of Earth Sciences, University of Vienna, 1090 Vienna, Austria
| | - Juha Saarinen
- Department of Geosciences and Geography, University of Helsinki, Helsinki, Finland
| | - Katharina Bastl
- Department of Palaeontology, Faculty of Earth Sciences, University of Vienna, 1090 Vienna, Austria
- Department of Oto-Rhino-Laryngology, Research Group Aerobiology and Pollen Information, Medical University of Vienna, Vienna, Austria
| | - Doris Nagel
- Department of Palaeontology, Faculty of Earth Sciences, University of Vienna, 1090 Vienna, Austria
| | - Friðgeir Grímsson
- Department of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria
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Grímsson F, Graham SA, Coiro M, Jacobs BF, Xafis A, Neumann FH, Scott L, Sakala J, Currano ED, Zetter R. Origin and divergence of Afro-Indian Picrodendraceae: linking pollen morphology, dispersal modes, fossil records, molecular dating and paleogeography. Grana 2019; 58:227-275. [PMID: 31275086 PMCID: PMC6582451 DOI: 10.1080/00173134.2019.1594357] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 02/19/2019] [Indexed: 05/31/2023]
Abstract
The pantropical Picrodendraceae produce mostly spheroidal to slightly oblate, echinate pollen grains equipped with narrow circular to elliptic pori that can be hard to identify to family level in both extant and fossil material using light microscopy only. Fossil pollen of the family have been described from the Paleogene of America, Antarctica, Australia, New Zealand, and Europe, but until now none have been reported from Afro-India. Extant pollen described here include representatives from all recent Picrodendraceae genera naturally occurring in Africa and/or Madagascar and south India and selected closely related tropical American taxa. Our analyses, using combined light microscopy and scanning electron microscopy, show that pollen of the Afro-Indian genera encompass three morphological types: Type 1, comprising only Hyaenanche; Type 2, including Aristogeitonia, Mischodon, Oldfieldia and Voatamalo; Type 3, comprising the remaining two genera, Androstachys and Stachyandra. Based on the pollen morphology presented here it is evident that some previous light microscopic accounts of spherical and echinate fossil pollen affiliated with Arecaceae, Asteraceae, Malvaceae, and Myristicaceae from the African continent could belong to Picrodendraceae. The pollen morphology of Picrodendraceae, fossil pollen records, a dated intra-familial phylogeny, seed dispersal modes, and the regional Late Cretaceous to early Cenozoic paleogeography, together suggest the family originated in the Americas and dispersed from southern America across Antarctica and into Australasia. A second dispersal route is believed to have occurred from the Americas into continental Africa via the North Atlantic Land Bridge and Europe.
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Affiliation(s)
- Friðgeir Grímsson
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | | | - Mario Coiro
- Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
| | - Bonnie F. Jacobs
- Roy M. Huffington Department of Earth Sciences, Southern Methodist University, Dallas, TX, USA
| | - Alexandros Xafis
- Department of Paleontology, University of Vienna, Vienna, Austria
| | - Frank H. Neumann
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
- Department of Plant Sciences, University of the Free State, Bloemfontein, South Africa
| | - Louis Scott
- Department of Plant Sciences, University of the Free State, Bloemfontein, South Africa
| | - Jakub Sakala
- Institute of Geology and Palaeontology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Ellen D. Currano
- Departments of Botany and Geology & Geophysics, University of Wyoming, Laramie, WY, USA
| | - Reinhard Zetter
- Department of Paleontology, University of Vienna, Vienna, Austria
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Grímsson F, van Valkenburg JL, Wieringa JJ, Xafis A, Jacobs BF, Zetter R. Pollen morphology of the African Sclerosperma (Arecaceae). Grana 2018; 58:99-113. [PMID: 30828286 PMCID: PMC6376959 DOI: 10.1080/00173134.2018.1519033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 08/11/2018] [Indexed: 06/09/2023]
Abstract
Three currently accepted Sclerosperma species appear to produce four different pollen morphologies. Sclerosperma mannii and S. walkeri pollen share the same distinct reticulate sculpture, but S. profizianum produces three different pollen types (microreticulate, fossulate, and perforate). The pollen morphology suggests that S. mannii and S. walkeri are sister taxa of the same intrageneric lineage. The pollen diversity observed in S. profizianum suggests (a) this taxon is unique regarding its pollen diversity despite being a non-heterostylous plant or (b) that circumscription of S. profizianum as a species may well be in the need of redefinition.
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Affiliation(s)
| | | | - Jan J. Wieringa
- Naturalis Biodiversity Center, National Herbarium of The Netherlands, Leiden, The Netherlands
| | - Alexandros Xafis
- Department of Palaeontology, University of Vienna, Vienna, Austria
| | - Bonnie F. Jacobs
- Roy M. Huffington Department of Earth Sciences, Southern Methodist University, Dallas, TX, USA
| | - Reinhard Zetter
- Department of Palaeontology, University of Vienna, Vienna, Austria
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Grímsson F, Jacobs BF, Van Valkenburg JLCH, Wieringa JJ, Xafis A, Tabor N, Pan AD, Zetter R. Sclerosperma fossils from the late Oligocene of Chilga, north-western Ethiopia. Grana 2018; 58:81-98. [PMID: 30828285 PMCID: PMC6382288 DOI: 10.1080/00173134.2018.1510977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 08/08/2018] [Indexed: 06/09/2023]
Abstract
The palm family, Arecaceae, is notoriously depauperate in Africa today, and its evolutionary, paleobiogeographic, and extinction history there are not well documented by fossils. In this article we report the pollen of two new extinct species of the small genus, Sclerosperma (Arecoideae), from a late Oligocene (27-28 Ma) stratum exposed along the Guang River in Chilga Wereda of north-western Ethiopia. The pollen are triporate, and the two taxa can be distinguished from each other and from modern species using a combination of light and scanning electron microscopy, which reveals variations in the finer details of their reticulate to perforate exine sculpture. We also report a palm leaf fragment from a stratum higher in the same section that is in the Arecoideae subfamily, and most likely belongs to Sclerosperma. The implications of these discoveries for the evolutionary history of this clade of African arecoid palms is that their diversification was well underway by the middle to late Oligocene, and they were much more widespread in Africa at that time than they are now, limited to West and Central Africa. Sclerosperma exhibits ecological conservatism, as today it occurs primarily in swamps and flooded forests, and the sedimentology of the Guang River deposits at Chilga indicate a heterogeneous landscape with a high water table. The matrix containing the fossil pollen is lignite, which itself indicates standing water, and a variety of plant macrofossils from higher in the section have been interpreted as representing moist tropical forest or seasonally inundated forest communities.
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Affiliation(s)
| | - Bonnie F. Jacobs
- Roy M. Huffington Department of Earth Sciences, Southern Methodist University, Dallas, TX, USA
| | | | - Jan J. Wieringa
- Naturalis Biodiversity Center, National Herbarium of The Netherlands, Leiden, The Netherlands
| | - Alexandros Xafis
- Department of Palaeontology, University of Vienna, Vienna, Austria
| | - Neil Tabor
- Roy M. Huffington Department of Earth Sciences, Southern Methodist University, Dallas, TX, USA
| | - Aaron D. Pan
- Don Harrington Discovery Center, Streit Drive, TX, USA
| | - Reinhard Zetter
- Department of Palaeontology, University of Vienna, Vienna, Austria
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Grímsson F, Xafis A, Neumann FH, Scott L, Bamford MK, Zetter R. The first Loranthaceae fossils from Africa. Grana 2018; 57:249-259. [PMID: 29780299 PMCID: PMC5940175 DOI: 10.1080/00173134.2018.1430167] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 12/13/2017] [Indexed: 05/31/2023]
Abstract
An ongoing re-investigation of the early Miocene Saldanha Bay (South Africa) palynoflora, using combined light and scanning electron microscopy (single grain method), is revealing several pollen types new to the African fossil record. One of the elements identified is Loranthaceae pollen. These grains represent the first and only fossil record of Loranthaceae in Africa. The fossil pollen grains resemble those produced by the core Lorantheae and are comparable to recent Asian as well as some African taxa/lineages. Molecular and fossil signals indicate that Loranthaceae dispersed into Africa via Asia sometime during the Eocene. The present host range of African Loranthaceae and the composition of the palynoflora suggest that the fossil had a range of potential host taxa to parasitise during the early Miocene in the Saldanha Bay region.
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Affiliation(s)
| | - Alexandros Xafis
- Department of Palaeontology, University of Vienna, Vienna, Austria
| | - Frank H. Neumann
- School of Agricultural, Earth and Environmental Sciences, University of KwaZulu-Natal, Pietermaritzburg, South Africa
- Department of Plant Sciences, University of the Free State, Bloemfontein, South Africa
| | - Louis Scott
- Department of Plant Sciences, University of the Free State, Bloemfontein, South Africa
| | - Marion K. Bamford
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
| | - Reinhard Zetter
- Department of Palaeontology, University of Vienna, Vienna, Austria
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Grímsson F, Grimm GW, Zetter R. Tiny pollen grains: first evidence of Saururaceae from the Late Cretaceous of western North America. PeerJ 2017; 5:e3434. [PMID: 28626610 PMCID: PMC5472062 DOI: 10.7717/peerj.3434] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 05/17/2017] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The Saururaceae, a very small family of Piperales comprising only six species in four genera, have a relatively scanty fossil record outside of Europe. The phylogenetic relationships of the four genera to each other are resolved, with the type genus Saururus occurring in both eastern North America and East Asia. No extant species occurs in western Eurasia. The most exceptional find so far has been an inflorescence with in-situ pollen, Saururus tuckerae S.Y.Sm. & Stockey from Eocene of North America with strong affinities to extant species of Saururus. Recent dated trees suggest, however, an Eocene or younger crown age for the family. METHODS Dispersed fossil pollen grains from the Campanian (82-81 Ma) of North America are compared to dispersed pollen grains from the Eocene strata containing S. tuckerae, the Miocene of Europe, and extant members of the family using combined LM and SEM imaging. RESULTS The unambiguous fossil record of the Saururaceae is pushed back into the Campanian (82-81 Ma). Comparison with re-investigated pollen from the Eocene of North America, the Miocene of Europe, and modern species of the family shows that pollen morphology in Saururaceae is highly conservative, and remained largely unchanged for the last 80 million years. DISCUSSION Campanian pollen of Saururaceae precludes young (Eocene or younger) estimates for the Saururaceae root and crown age, but is in-line with maximum age scenarios. Saururus-type pollen appear to represent the primitive pollen morphology of the family. Often overlooked because of its small size, dispersed Saururaceae pollen may provide a unique opportunity to map the geographic history of a small but old group of Piperales, and should be searched for in Paleogene and Cretaceous sediment samples.
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Affiliation(s)
| | - Guido W Grimm
- Department of Palaeontology, University of Vienna, Vienna, Austria
- Unaffiliated, Orléans, France
| | - Reinhard Zetter
- Department of Palaeontology, University of Vienna, Vienna, Austria
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Grímsson F, Kapli P, Hofmann CC, Zetter R, Grimm GW. Eocene Loranthaceae pollen pushes back divergence ages for major splits in the family. PeerJ 2017; 5:e3373. [PMID: 28607837 PMCID: PMC5466002 DOI: 10.7717/peerj.3373] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 05/04/2017] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND We revisit the palaeopalynological record of Loranthaceae, using pollen ornamentation to discriminate lineages and to test molecular dating estimates for the diversification of major lineages. METHODS Fossil Loranthaceae pollen from the Eocene and Oligocene are analysed and documented using scanning-electron microscopy. These fossils were associated with molecular-defined clades and used as minimum age constraints for Bayesian node dating using different topological scenarios. RESULTS The fossil Loranthaceae pollen document the presence of at least one extant root-parasitic lineage (Nuytsieae) and two currently aerial parasitic lineages (Psittacanthinae and Loranthinae) by the end of the Eocene in the Northern Hemisphere. Phases of increased lineage diversification (late Eocene, middle Miocene) coincide with global warm phases. DISCUSSION With the generation of molecular data becoming easier and less expensive every day, neontological research should re-focus on conserved morphologies that can be traced through the fossil record. The pollen, representing the male gametophytic generation of plants and often a taxonomic indicator, can be such a tracer. Analogously, palaeontological research should put more effort into diagnosing Cenozoic fossils with the aim of including them into modern systematic frameworks.
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Affiliation(s)
| | - Paschalia Kapli
- The Exelixis Lab, Scientific Computing Group, Heidelberg Institute for Theoretical Studies, Heidelberg, Germany
| | | | - Reinhard Zetter
- Department of Palaeontology, University of Vienna, Wien, Austria
| | - Guido W. Grimm
- Department of Palaeontology, University of Vienna, Wien, Austria
- Orléans, France
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Abstract
Earlier studies indicate a strong correlation of pollen morphology and ultrastructure with taxonomy in Loranthaceae. Using high-resolution light microscopy and scanning electron microscopy imaging of the same pollen grains, we document pollen types of 35 genera including 15 studied for the first time. Using a molecular phylogenetic framework based on currently available sequence data with good genus-coverage, we reconstruct trends in the evolution of Loranthaceae pollen and pinpoint traits of high diagnostic value, partly confirming earlier intuitive hypotheses based on morphological observations. We find that pollen morphology in Loranthaceae is strongly linked to phylogenetic relationships. Some pollen types are diagnostic for discrete genera or evolutionary lineages, opening the avenue to recruit dispersed fossil pollen as age constraints for dated phylogenies and as independent data for testing biogeographic scenarios; so far based exclusively on modern-day data. Correspondences and discrepancies between palynological and molecular data and current taxonomic/systematic concepts are identified and suggestions made for future palynological and molecular investigations of Loranthaceae.
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Affiliation(s)
| | - Guido W. Grimm
- Department of Palaeontology, University of Vienna, Vienna, Austria
| | - Reinhard Zetter
- Department of Palaeontology, University of Vienna, Vienna, Austria
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Wappler T, Labandeira CC, Engel MS, Zetter R, Grímsson F. Specialized and Generalized Pollen-Collection Strategies in an Ancient Bee Lineage. Curr Biol 2015; 25:3092-8. [PMID: 26585282 PMCID: PMC6485464 DOI: 10.1016/j.cub.2015.09.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 09/07/2015] [Accepted: 09/08/2015] [Indexed: 10/22/2022]
Abstract
Iconic examples of insect pollination have emphasized narrowly specialized pollinator mutualisms such as figs and fig wasps and yuccas and yucca moths. However, recent attention by pollination ecologists has focused on the broad spectra of pollinated plants by generalist pollinators such as bees. Bees have great impact for formulating hypotheses regarding specialization versus generalization in pollination mutualisms. We report the pollination biology of six northern European species of an extinct tribe of pollen-basket-bearing apine bees, Electrapini, of early-middle Eocene age, examined from two deposits of 48 and 44 million years in age. These bees exhibit a pattern of generalized, incidental pollen occurring randomly on their heads, thoraces, and abdomens, obtained from diverse, nectar-bearing plants. By contrast, a more restricted suite of pollen was acquired for metatibial pollen baskets (corbiculae) of the same bee taxa from a taxonomically much narrower suite of arborescent, evergreen hosts with uniform flower structure. The stereotyped plant sources of the specialist strategy of pollen collection consisted of pentamerous, radially symmetrical flowers with a conspicuous gynoecium surrounded by prominent nectar reward, organized in structurally similar compound inflorescences. Pollen specialization in bees occurs not for efficient pollination but rather in the corbiculate Electrapini as food for bee larvae (brood) and involves packing corbiculae with moistened pollen that rapidly loses viability with age. This specialist strategy was a well-developed preference by the early Eocene, providing a geochronologic midpoint assessment of bee pollen-collection strategies.
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Affiliation(s)
- Torsten Wappler
- Steinmann Institute, University of Bonn, Nussallee 8, 53115 Bonn, Germany.
| | - Conrad C Labandeira
- Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013-7012, USA; Department of Entomology, University of Maryland, College Park, MD 20742, USA; College of Life Sciences, Capital Normal University, Beijing 100048, China.
| | - Michael S Engel
- Division of Entomology, Natural History Museum, University of Kansas, Lawrence, KS 66045, USA; Department of Ecology & Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA; Division of Invertebrate Zoology, American Museum of Natural History, New York, NY 10024, USA
| | - Reinhard Zetter
- Department of Palaeontology, University of Vienna, Althanstraße 14 (UZAII), 1090 Vienna, Austria
| | - Friðgeir Grímsson
- Department of Palaeontology, University of Vienna, Althanstraße 14 (UZAII), 1090 Vienna, Austria
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Manchester SR, Grímsson F, Zetter R. Assessing the Fossil Record of Asterids in the Context of Our Current Phylogenetic Framework. Ann Mo Bot Gard 2015; 100:329-363. [PMID: 31031419 PMCID: PMC6485501 DOI: 10.3417/2014033] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The fossil record provides good evidence for the minimum ages of important events in the diversification and geographic spread of Asteridae, with earliest examples extending back to the Turonian stage of the Late Cretaceous (~89 Ma). Some of the fossil identifications accepted in previous considerations of asterid phylogeny do not stand up to careful scrutiny. Nevertheless, among major clades of asterids, there is good evidence for a range of useful anchor points. Here we provide a synopsis of fossil occurrences that we consider as reliable representatives of modern Asterid families and genera. In addition, we provide new examples documented by fossil dispersed pollen investigated by both light and scanning electron microscopy studies including representatives of Loranthaceae, Amaranthaceae, Cornaceae (incl. Nyssa L., Mastixia Blume, Diplopanax Hand.-Mazz.), Sapotaceae, Ebenaceae, Ericaceae, Icacinaceae, Oleaceae, Asteraceae, Araliaceae, Adoxaceae and Caprifoliaceae from Paleogene sites in Greenland, western North America, and central Europe, and of Lamiaceae and Asteraceae from the middle to late Miocene northeastern China. We emphasize that dispersed pollen, taken along with megafossil and mesofossil data, continue to fill gaps in our knowledge of the paleobotanical record.
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Affiliation(s)
| | - Friðgeir Grímsson
- University of Vienna, Department of Palaeontology, Althanstraße 14 (UZA II), A-1090, Vienna, Austria
| | - Reinhard Zetter
- University of Vienna, Department of Palaeontology, Althanstraße 14 (UZA II), A-1090, Vienna, Austria
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Grímsson F, Zetter R, Grimm GW, Pedersen GK, Pedersen AK, Denk T. Fagaceae pollen from the early Cenozoic of West Greenland: revisiting Engler's and Chaney's Arcto-Tertiary hypotheses. Plant Syst Evol 2015; 301:809-832. [PMID: 25620836 PMCID: PMC4299674 DOI: 10.1007/s00606-014-1118-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 06/27/2014] [Indexed: 05/12/2023]
Abstract
In this paper we document Fagaceae pollen from the Eocene of western Greenland. The pollen record suggests a remarkable diversity of the family in the early Cenozoic of Greenland. Extinct Fagaceae pollen types include Eotrigonobalanus, which extends at least back to the Paleocene, and two ancestral pollen types with affinities to the Eurasian Quercus Group Ilex and the western North American Quercus Group Protobalanus. In addition, modern lineages of Fagaceae are unambiguously represented by pollen of Fagus, Quercus Group Lobatae/Quercus, and three Castaneoideae pollen types. These findings corroborate earlier findings from Axel Heiberg Island that Fagaceae were a dominant element at high latitudes during the early Cenozoic. Comparison with coeval or older mid-latitude records of modern lineages of Fagaceae shows that modern lineages found in western Greenland and Axel Heiberg likely originated at lower latitudes. Further examples comprise (possibly) Acer, Aesculus, Alnus, Ulmus, and others. Thus, before fossils belonging to modern northern temperate lineages will have been recovered from older (early Eocene, Paleocene) strata from high latitudes, Engler's hypothesis of an Arctic origin of the modern temperate woody flora of Eurasia, termed 'Arcto-Tertiary Element', and later modification by R. W. Chaney and H. D. Mai ('Arcto-Tertiary Geoflora') needs to be modified.
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Affiliation(s)
| | - Reinhard Zetter
- Department of Palaeontology, University of Vienna, Vienna, Austria
| | - Guido W. Grimm
- Department of Palaeobiology, Swedish Museum of Natural History, Stockholm, Sweden
| | - Gunver Krarup Pedersen
- Department of Stratigraphy, Geological Survey of Denmark and Greenland, Copenhagen, Denmark
| | - Asger Ken Pedersen
- Geological Museum, Natural History Museum of Denmark, Copenhagen, Denmark
| | - Thomas Denk
- Department of Palaeobiology, Swedish Museum of Natural History, Stockholm, Sweden
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Bouchal J, Zetter R, Grímsson F, Denk T. Evolutionary trends and ecological differentiation in early Cenozoic Fagaceae of western North America. Am J Bot 2014; 101:1-5. [PMID: 25156982 DOI: 10.3732/ajb.1300450] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
UNLABELLED • PREMISE OF THE STUDY The early Cenozoic was a key period of evolutionary radiation in Fagaceae. The common notion is that species thriving in the modern summer-dry climate of California originated in climates with ample summer rain during the Paleogene.• METHODS We investigated in situ and dispersed pollen of Fagaceae from the uppermost Eocene Florissant fossil beds, Colorado, United States, using a combined light and scanning electron microscopy approach.• KEY RESULTS Pollen types of Castaneoideae with affinities to modern Castanea, Lithocarpus, and Castanopsis were recognized. Pollen of the extinct genus Fagopsis represents a derived type of Castaneoideae pollen. Infrageneric groups of Quercus were well represented, including pollen of Group Protobalanus. The taxonomic diversity of Fagaceae and of the total plant assemblage indicates a mosaic of microclimates, that range from pronounced to weakly seasonal climates and depend on slope aspect and elevation. Continental climatic conditions may have triggered the evolution of sclerophyllous leaves and adaptive radiation in Quercus and other taxa thriving today under distinctly summer-dry and winter-dry climates.• CONCLUSIONS Vegetation types similar to modern vegetation belts of the Coastal Ranges (chaparral, nemoral conifer forest) were established in the Front Range in the late Eocene. Coeval plant assemblages from the Coastal Ranges of California indicate distinctly subtropical, moist climates. Hence, characteristic elements found today in the summer-dry and winter-dry climates of Pacific North America (Quercus Group Protobalanus, Notholithocarpus) may opportunistically have dispersed into their modern ranges later in the Cenozoic. This scenario is in contrast to the evolution and migration patterns of their western Eurasian Mediterranean counterparts (Quercus Group Ilex).
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Affiliation(s)
- Johannes Bouchal
- Swedish Museum of Natural History, Department of Palaeobiology, Box 50007, 10405 Stockholm, Sweden University of Vienna, Department of Palaeontology, Althanstraße 14 (UZA II), A-1090 Vienna, Austria
| | - Reinhard Zetter
- University of Vienna, Department of Palaeontology, Althanstraße 14 (UZA II), A-1090 Vienna, Austria
| | - Friðgeir Grímsson
- University of Vienna, Department of Palaeontology, Althanstraße 14 (UZA II), A-1090 Vienna, Austria University of Iceland, Institute of Earth Sciences, Sturlugata 7, 101 Reykjavík, Iceland
| | - Thomas Denk
- Swedish Museum of Natural History, Department of Palaeobiology, Box 50007, 10405 Stockholm, Sweden
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Bouchal J, Zetter R, Grímsson F, Denk T. Evolutionary trends and ecological differentiation in early Cenozoic Fagaceae of western North America. Am J Bot 2014; 101:1332-49. [PMID: 25156982 PMCID: PMC6485467 DOI: 10.3732/ajb.1400118] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
UNLABELLED • PREMISE OF THE STUDY The early Cenozoic was a key period of evolutionary radiation in Fagaceae. The common notion is that species thriving in the modern summer-dry climate of California originated in climates with ample summer rain during the Paleogene.• METHODS We investigated in situ and dispersed pollen of Fagaceae from the uppermost Eocene Florissant fossil beds, Colorado, United States, using a combined light and scanning electron microscopy approach.• KEY RESULTS Pollen types of Castaneoideae with affinities to modern Castanea, Lithocarpus, and Castanopsis were recognized. Pollen of the extinct genus Fagopsis represents a derived type of Castaneoideae pollen. Infrageneric groups of Quercus were well represented, including pollen of Group Protobalanus. The taxonomic diversity of Fagaceae and of the total plant assemblage indicates a mosaic of microclimates, that range from pronounced to weakly seasonal climates and depend on slope aspect and elevation. Continental climatic conditions may have triggered the evolution of sclerophyllous leaves and adaptive radiation in Quercus and other taxa thriving today under distinctly summer-dry and winter-dry climates.• CONCLUSIONS Vegetation types similar to modern vegetation belts of the Coastal Ranges (chaparral, nemoral conifer forest) were established in the Front Range in the late Eocene. Coeval plant assemblages from the Coastal Ranges of California indicate distinctly subtropical, moist climates. Hence, characteristic elements found today in the summer-dry and winter-dry climates of Pacific North America (Quercus Group Protobalanus, Notholithocarpus) may opportunistically have dispersed into their modern ranges later in the Cenozoic. This scenario is in contrast to the evolution and migration patterns of their western Eurasian Mediterranean counterparts (Quercus Group Ilex).
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Affiliation(s)
- Johannes Bouchal
- Swedish Museum of Natural History, Department of Palaeobiology, Box 50007, 10405 Stockholm, Sweden
- University of Vienna, Department of Palaeontology, Althanstraße 14 (UZA II), A-1090 Vienna, Austria
| | - Reinhard Zetter
- University of Vienna, Department of Palaeontology, Althanstraße 14 (UZA II), A-1090 Vienna, Austria
| | - Friðgeir Grímsson
- University of Vienna, Department of Palaeontology, Althanstraße 14 (UZA II), A-1090 Vienna, Austria
- University of Iceland, Institute of Earth Sciences, Sturlugata 7, 101 Reykjavík, Iceland
| | - Thomas Denk
- Swedish Museum of Natural History, Department of Palaeobiology, Box 50007, 10405 Stockholm, Sweden
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Grímsson F, Zetter R, Halbritter H, Grimm GW. Aponogeton pollen from the Cretaceous and Paleogene of North America and West Greenland: Implications for the origin and palaeobiogeography of the genus. Rev Palaeobot Palynol 2014; 200:161-187. [PMID: 24926107 PMCID: PMC4047627 DOI: 10.1016/j.revpalbo.2013.09.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 09/04/2013] [Accepted: 09/22/2013] [Indexed: 05/26/2023]
Abstract
The fossil record of Aponogeton (Aponogetonaceae) is scarce and the few reported macrofossil findings are in need of taxonomic revision. Aponogeton pollen is highly diagnostic and when studied with light microscopy (LM) and scanning electron microscopy (SEM) it cannot be confused with any other pollen types. The fossil Aponogeton pollen described here represent the first reliable Cretaceous and Eocene records of this genus worldwide. Today, Aponogeton is confined to the tropics and subtropics of the Old World, but the new fossil records show that during the late Cretaceous and early Cenozoic it was thriving in North America and Greenland. The late Cretaceous pollen record provides important data for future phylogenetic and phylogeographic studies focusing on basal monocots, especially the Alismatales. The Eocene pollen morphotypes from North America and Greenland differ in morphology from each other and also from the older Late Cretaceous North American pollen morphotype, indicating evolutionary trends and diversification within the genus over that time period. The presence of Aponogeton in the fossil record of North America and Greenland calls for a reconsideration of all previous ideas about the biogeographic history of the family.
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Affiliation(s)
- Friðgeir Grímsson
- University of Vienna, Department of Palaeontology, Althanstraße 14 (UZA II), Vienna, Austria
| | - Reinhard Zetter
- University of Vienna, Department of Palaeontology, Althanstraße 14 (UZA II), Vienna, Austria
| | - Heidemarie Halbritter
- University of Vienna, Department of Structural and Functional Botany, Rennweg 14, Vienna, Austria
| | - Guido W. Grimm
- Swedish Museum of Natural History, Department of Palaeobiology, Box 50007, 10405 Stockholm, Sweden
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Grímsson F, Zetter R, Hofmann CC. Lythrum and Peplis from the Late Cretaceous and Cenozoic of North America and Eurasia: new evidence suggesting early diversification within the Lythraceae. Am J Bot 2011; 98:1801-15. [PMID: 22025296 DOI: 10.3732/ajb.1100204] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
PREMISE OF THE STUDY To fully understand the evolution of today's angiosperms, the fossil record of plant families and genera must be used to determine their time of origin and phytogeographic history. As within many angiosperm families, the interrelationships of extant Lythraceae are hard to resolve without sufficient data from the geological past. Here we establish the earliest fossil occurrences of Lythraceae and start resolving the interrelationships and evolution of two of its genera, Lythrum and Peplis. METHODS We studied several Cretaceous and Cenozoic palynofloras from the northern and southern hemispheres. Using the single-grain technique, we screened the treated samples for Lythrum- and Peplis-type pollen. The same individual pollen grains were observed under both the light- and scanning electron microscope, allowing a high taxonomic resolution to be achieved. KEY RESULTS Fossil Lythraceae pollen grains are rare in palynological samples. Nevertheless, we were able to identify Lythrum and Peplis pollen from Late Cretaceous sediments and thereby extend the fossil record of the two genera by ca 70 million years. CONCLUSIONS The appearance of Lythrum and Peplis in North America and Peplis in Asia at approximately the same interval in the mid Late Cretaceous points to an already wide geographical distribution by then. These findings add vital information for the time of origin of the Lythraceae and suggest a higher diversity within the family. They also indicate that the distribution of particular genera during the Cretaceous was wider than previously thought.
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Affiliation(s)
- Friðgeir Grímsson
- University of Vienna, Department of Palaeontology, Althanstraße 14, A-1090 Vienna, Austria.
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Denk T, Grímsson F, Zetter R. Episodic migration of oaks to Iceland: Evidence for a North Atlantic "land bridge" in the latest Miocene. Am J Bot 2010; 97:276-287. [PMID: 21622388 DOI: 10.3732/ajb.0900195] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Dating the subsidence history of the North Atlantic Land Bridge (NALB) is crucial for understanding intercontinental disjunctions of northern temperate trees. Traditionally, the NALB has been assumed to have functioned as a corridor for plant migration only during the early Cenozoic, but recent findings of plant fossils and inferences from molecular studies are challenging this view. Here, we report dispersed pollen of Quercus from Late Miocene sediments in Iceland that shows affinities with extant northern hemispheric white oaks and North American red oaks. Older (15 to 10 Ma) sediments do not contain pollen of Quercus suggesting it arrived after that time. Pollen from the 9-8 Ma Hrútagil locality is indistinguishable from morphotypes common among white and red oaks. In contrast, pollen from the 5.5 Ma Selárgil locality has a tectum that is at present confined to North American white and red oaks, indicating a second episode of migration to Iceland. These findings suggest that transatlantic migration of temperate plant taxa may not have been limited by vast areas of sea or by cold climates during the Miocene. Furthermore, our results offer a plausible explanation for the remarkably low degree of genetic differentiation between modern disjunct European and North American oaks.
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Affiliation(s)
- Thomas Denk
- Department of Palaeobotany, Swedish Museum of Natural History, Box 5007, 104 05 Stockholm, Sweden
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