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Premise of the Study: The fossil record of Agathis historically has been restricted to Australasia. Recently described fossils from the Eocene of Patagonian Argentina showed a broader distribution than found previously, which is reinforced here with a new early Paleocene Agathis species from Patagonia. No previous phylogenetic analyses have included fossil Agathis species. Methods: We describe macrofossils from Patagonia of Agathis vegetative and reproductive organs from the early Danian, as well as leaves with Agathis affinities from the latest Maastrichtian. A total evidence phylogenetic analysis is performed, including the new Danian species together with other fossil species having agathioid affinities. Key Results: Early Danian Agathis immortalis sp. nov. is the oldest definite occurrence of Agathis and one of the most complete Agathis species in the fossil record. Leafy twigs, leaves, pollen cones, pollen, ovuliferous complexes, and seeds show features that are extremely similar to the living genus. Dilwynites pollen grains, associated today with both Wollemia and Agathis and known since the Turonian, were found in situ within the pollen cones. Conclusions: Agathis was present in Patagonia ca. 2 million years after the K‐Pg boundary, and the putative latest Cretaceous fossils suggest that the genus survived the K–Pg extinction. Agathis immortalis sp nov. is recovered in a stem position for the genus, while A. zamunerae (Eocene, Patagonia) is recovered as part of the crown. A Mesozoic divergence for the Araucariaceae crown group, previously challenged by molecular divergence estimates, is supported by the combined phylogenetic analyses including the fossil taxa. [ABSTRACT FROM AUTHOR]

* Premise of the study: Agathis is an iconic genus of large, ecologically important, and economically valuable conifers that range over lowland to upper montane rainforests from New Zealand to Sumatra. Exploitation of its timber and copal has greatly reduced the genus's numbers. The early fossil record of Agathis comes entirely from Australia, often presumed to be its area of origin. Agathis has no previous record from South America. * Methods: We describe abundant macrofossils of Agathis vegetative and reproductive organs, from early and middle Eocene rainforest paleofloras of Patagonia, Argentina. The leaves were formerly assigned to the New World cycad genus Zamia. * Key results: Agathis zamunerae sp. nov. is the first South American occurrence and the most complete representation of Agathis in the fossil record. Its morphological features are fully consistent with the living genus. The most similar living species is A. lenticula, endemic to lower montane rainforests of northern Borneo. * Conclusions: Agathis zamunerae sp. nov. demonstrates the presence of modern-aspect Agathis by 52.2 mya and vastly in creases the early range and possible areas of origin of the genus. The revision from Zamia breaks another link between the Eocene and living floras of South America. Agathis was a dominant, keystone element of the Patagonian Eocene floras, along side numerous other plant taxa that still associate with it in Australasia and Southeast Asia. Agathis extinction in South America was an integral part of the transformation of Patagonian biomes over millions of years, but the living species are disappearing from their ranges at a far greater rate. [ABSTRACT FROM AUTHOR]

Premise of research. Phylogenetic relationships of Araucariaceae (Coniferophyta, Araucariales) are revised on the basis of the first combined data matrix for the family. Methodology. Taxon sampling includes 39 ingroup species (31 extant, 8 fossils) and outgroup species of all the remaining conifer families. Five fossil Araucaria species, one species of the genus Araucarites, and two species of the extinct genera Wairarapaia and Emwadea were included in the analyses. Character sampling includes 23 genomic regions (19 plastid, 2 nuclear, and 2 mitochondrial) and 62 morphological characters (52 discrete and 10 continuous). The phylogenetic analyses were conducted with equally weighted parsimony. Additionally, several analyses under different taxon- and gene-sampling regimes were analyzed for identifying the causes of the long-lasting controversies in the interrelationships of the three extant genera of Araucariaceeae. Pivotal results. Monophyletic Araucariaceae is the sister group of Podocarpaceae, forming the order Araucariales. Monophyly of Araucaria and Agathis is also strongly supported by the data. The results of both molecular and combined analyses indicate that Wollemia and Agathis form a clade (pagathioid clade) sister to Araucaria. Within Araucaria, the analyses support the monophyly of the four currently recognized sections: Araucaria, Bunya, Intermedia, and Eutacta. Results support the monophyly of living and fossil Araucaria (including Araucarites), whereas the remaining extinct genera are placed as the stem of the agathioid clade. In terms of the sensitivity analyses performed, results suggest that inconsistencies among previous results would be related to ingroup sampling. Conclusions. By means of a combined phylogenetic analysis, we have been able to obtain a strongly supported and well-resolved phylogeny of Araucariaceae that includes both living species and fossil species for the group. This study shows the feasibility and usefulness of phylogenetic analyses that incorporate multiple sources of evidence (molecules/morphology, living/fossil species, discrete/continuous characters). [ABSTRACT FROM AUTHOR]