Fossil insect-feeding traces indicate unrecognized evolutionary history and biodiversity on Australia's iconic Eucalyptus.

Fossilized plant-insect herbivore associations provide fundamental information about the assembly of terrestrial communities through geologic time. However, fossil evidence of associations originating in deep time and persisting to the modern day is scarce. We studied the insect herbivore damage found on 284 Eucalyptus frenguelliana leaves from the early Eocene Laguna del Hunco rainforest locality in Argentinean Patagonia and compared damage patterns with those observed on extant, rainforest-associated Eucalyptus species from Australasia (> 10 000 herbarium sheets reviewed).

Early Eocene infructescences from Argentine Patagonia expand the biogeography of Malvoideae.

Premise: Fossil infructescences and isolated fruits with characters of Malvoideae, a subfamily of Malvaceae (mallow family), were collected from early Eocene sediments in Chubut, Argentina. The main goals of this research are to describe and place these fossils systematically, and to explore their biogeographical implications.

Methods: Fossils were collected at the Laguna del Hunco site, Huitrera Formation, Chubut, Patagonia, Argentina.

A new fossil Acmopyle with accessory transfusion tissue and potential reproductive buds: Direct evidence for ever-wet rainforests in Eocene Patagonia.

Premise: Acmopyle (Podocarpaceae) comprises two extant species from Oceania that are physiologically restricted to ever-wet rainforests, a confirmed fossil record based on leaf adpressions and cuticles in Australia since the Paleocene, and a few uncertain reports from New Zealand, Antarctica, and South America. We investigated fossil specimens with Acmopyle affinities from the early Eocene Laguna del Hunco site in Patagonia, Argentina.

Methods: We studied 42 adpression leafy-shoot fossils and included them in a total evidence phylogenetic analysis.

The first Gondwanan Euphorbiaceae fossils reset the biogeographic history of the Macaranga-Mallotus clade.

Premise: The spurge family Euphorbiaceae is prominent in tropical rainforests worldwide, particularly in Asia. There is little consensus on the biogeographic origins of the family or its principal lineages. No confirmed spurge macrofossils have come from Gondwana.

Cunoniaceae infructescences from the early Eocene Laguna del Hunco flora, Patagonia, Argentina.

Premise: Two distinct types of fossil infructescences from the early Eocene Laguna del Hunco flora, Chubut Province, Patagonia, Argentina, preserve features of the family Cunoniaceae. The goal of the study was to assess their affinities within Cunoniaceae and to interpret their evolutionary and biogeographical significance.

Methods: Specimens were collected from the Tufolitas Laguna del Hunco, Huitrera Formation.

An image dataset of cleared, x-rayed, and fossil leaves vetted to plant family for human and machine learning.

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.

Paleoaltingia gen. nov., a new genus of Altingiaceae from the Late Cretaceous of New Jersey.

Premise: Altingiaceae is a small family with a bimodal Northern Hemisphere distribution in eastern North America and eastern Asia, and a rich Cenozoic fossil record. The charcoalified fossil infructescence Paleoaltingia gen. nov.

52 million years old Eucalyptus flower sheds more than pollen grains.

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.

New physaloid fruit-fossil species from early Eocene South America.

Premise: Solanaceae is a scientifically and economically important angiosperm family with a minimal fossil record and an intriguing early evolutionary history. Here, we report a newly discovered fossil lantern fruit with a suite of features characteristic of Physalideae within Solanaceae. The fossil comes from the early Eocene Laguna del Hunco site (ca.

Conifer wood assemblage dominated by Podocarpaceae, early Eocene of Laguna del Hunco, central Argentinean Patagonia.

During the early Eocene, Patagonia had highly diverse floras that are primarily known from compression and pollen fossils. Fossil wood studies from this epoch are scarce in the region and largely absent from the Laguna del Hunco flora, which has a highly diverse and excellently preserved compression assemblage. A collection of 26 conifer woods from the Laguna del Hunco fossil-lake beds (early Eocene, ca.

Fossil evidence from South America for the diversification of Cunoniaceae by the earliest Palaeocene.

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.

Reinterpretation of Paleoazolla: a heterosporous water fern from the Late Cretaceous of Patagonia, Argentina.

Premise: Undoubtedly, fossils are critical for understanding evolutionary transformations in deep time. Here, we reinvestigate the microspores and megaspores of Paleoazolla patagonica, a water fern found in Late Cretaceous sediments of the Chubut Province, Patagonia, Argentina, which provides novel evidence on the past history of the water fern clade. The study was based on recently collected specimens and additional observations of the original material.

Response to Comment on "Eocene Fagaceae from Patagonia and Gondwanan legacy in Asian rainforests".

Denk agree that we reported the first fossil Fagaceae from the Southern Hemisphere. We appreciate their general enthusiasm for our findings, but we reject their critiques, which we find misleading and biased. The new fossils unequivocally belong to , and substantial evidence supports our Southern Route to Asia hypothesis.

The Plant Ontology Facilitates Comparisons of Plant Development Stages Across Species.

The Plant Ontology (PO) is a community resource consisting of standardized terms, definitions, and logical relations describing plant structures and development stages, augmented by a large database of annotations from genomic and phenomic studies. This paper describes the structure of the ontology and the design principles we used in constructing PO terms for plant development stages. It also provides details of the methodology and rationale behind our revision and expansion of the PO to cover development stages for all plants, particularly the land plants (bryophytes through angiosperms).

Eocene Fagaceae from Patagonia and Gondwanan legacy in Asian rainforests.

The beech-oak family Fagaceae dominates forests from the northern temperate zone to tropical Asia and Malesia, where it reaches its southern limit. We report early Eocene infructescences of , a diverse and abundant fagaceous genus of Southeast Asia, and co-occurring leaves from the 52-million-year-old Laguna del Hunco flora of southern Argentina. The fossil assemblage notably includes many plant taxa that associate with today.

Monocot plastid phylogenomics, timeline, net rates of species diversification, the power of multi-gene analyses, and a functional model for the origin of monocots.

Premise Of The Study: We present the first plastome phylogeny encompassing all 77 monocot families, estimate branch support, and infer monocot-wide divergence times and rates of species diversification.

Methods: We conducted maximum likelihood analyses of phylogeny and BAMM studies of diversification rates based on 77 plastid genes across 545 monocots and 22 outgroups. We quantified how branch support and ascertainment vary with gene number, branch length, and branch depth.

Araucaria lefipanensis (Araucariaceae), a new species with dimorphic leaves from the Late Cretaceous of Patagonia, Argentina.

Premise Of The Study: We describe a new araucarian species, Araucaria lefipanensis, from the Late Cretaceous flora of the Lefipán Formation, in Patagonia (Argentina) based on reproductive and vegetative remains, with a combination of characters that suggest mosaic evolution in the Araucaria lineage.

Methods: The studied fossils were found at the Cañadón del Loro locality. Specimens were separated into two leaf morphotypes, and their morphological differences were tested with MANOVA.

A late Cretaceous fagalean inflorescence preserved in amber from New Jersey.

Premise Of The Study: An inflorescence with three pistillate flowers in amber from the early Upper Cretaceous (Turonian, ~90-94 million years ago) of central New Jersey represents the oldest known flowers with features present in an early stem complex of the Fagales. The inflorescence has characteristics of Nothofagaceae, but also has strikingly distinct characters that suggest it is intermediate between Nothofagus and other Fagales. This intermediacy is consistent with its northern hemisphere distribution.

The fossil flip-leaves (Retrophyllum, Podocarpaceae) of southern South America.

Premise Of The Study: The flip-leaved podocarp Retrophyllum has a disjunct extant distribution in South American and Australasian tropical rainforests and a Gondwanic fossil record since the Eocene. Evolutionary, biogeographic, and paleoecological insights from previously described fossils are limited because they preserve little foliar variation and no reproductive structures.

Methods: We investigated new Retrophyllum material from the terminal Cretaceous Lefipán, the early Eocene Laguna del Hunco, and the early/middle Eocene Río Pichileufú floras of Patagonian Argentina.

Fossil moonseeds from the Paleogene of West Gondwana (Patagonia, Argentina).

Premise Of The Study: The fossil record is critical for testing biogeographic hypotheses. Menispermaceae (moonseeds) are a widespread family with a rich fossil record and alternative hypotheses related to their origin and diversification. The family is well-represented in Cenozoic deposits of the northern hemisphere, but the record in the southern hemisphere is sparse.

Fossil flowers from the early Palaeocene of Patagonia, Argentina, with affinity to Schizomerieae (Cunoniaceae).

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.

Flowering after disaster: Early Danian buckthorn (Rhamnaceae) flowers and leaves from Patagonia.

Southern-Hemisphere terrestrial communities from the early Paleocene are poorly known, but recent work on Danian plant fossils from the Salamanca Formation in Chubut Province, Argentina are providing critical data on earliest Paleocene floras. The fossils described here come from a site in the Salamanca Formation dating to ca. 1 million years or less after the end-Cretaceous extinction event; they are the first fossil flowers reported from the Danian of South America, and possible the entire Southern Hemisphere.

Ceratopetalum (Cunoniaceae) fruits of Australasian affinity from the early Eocene Laguna del Hunco flora, Patagonia, Argentina.

Background And Aims: Radially symmetrical, five-winged fossil fruits from the highly diverse early Eocene Laguna del Hunco flora of Chubut Province, Patagonia, Argentina, are named, described and illustrated. The main goals are to assess the affinities of the fossils and to place them in an evolutionary, palaeoecological and biogeographic context.

Methods: Specimens of fossil fruits were collected from the Tufolitas Laguna del Hunco.

Eocene lantern fruits from Gondwanan Patagonia and the early origins of Solanaceae.

The nightshade family Solanaceae holds exceptional economic and cultural importance. The early diversification of Solanaceae is thought to have occurred in South America during its separation from Gondwana, but the family's sparse fossil record provides few insights. We report 52.

Late cretaceous aquatic plant world in Patagonia, Argentina.

In this contribution, we describe latest Cretaceous aquatic plant communities from the La Colonia Formation, Patagonia, Argentina, based on their taxonomic components and paleoecological attributes. The La Colonia Formation is a geological unit deposited during a Maastrichtian-Danian transgressive episode of the South Atlantic Ocean. This event resulted in the deposition of a series of fine-grained sediments associated with lagoon systems occurring along irregular coastal plains in northern Patagonia.