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Summary Cunoniaceae are important elements of rainforests across the Southern Hemisphere. Many of these flowering plants are considered Paleo‐Antarctic Rainforest Lineages that had a Gondwanan distribution since the Paleocene. Fossils of several modern genera within the family, such asCeratopetalum, have indicated biogeographical connections between South America and Australia in the Cenozoic.Here, we report a dramatic geographical range extension forCeratopetalum, and Cunoniaceae as a whole, based on two exceptionally preserved fossil winged fruits from Campanian (c. 82–80 Ma old) deposits on Sucia Island, Washington, USA. The fossils were studied using physical sectioning, light microscopy, micro‐computed tomography scanning and multiple phylogenetic analyses.The fossil fruits share diagnostic characters withCeratopetalumsuch as the presence of four to five persistent calyx lobes, a prominent nectary disk, persistent stamens, a semi‐inferior ovary and two persistent styles. Based on morphological comparisons with fruits of extant species and support from phylogenetic analyses, the fossils are assigned to a new speciesCeratopetalum suciensis.These fossils are the first unequivocal evidence of crown Cunoniaceae from the Cretaceous of North America, indicating a more complicated biogeographical history for this important Gondwanan family.
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A permineralized Early Cretaceous lycopsid from China and the evolution of crown clubmosses
Summary Lycopodiaceae are one of three surviving families of lycopsids, a lineage of vascular plants with a fossil history dating to at least the Early Devonian or perhaps the Late Silurian (c. 415 Ma). Many fossils have been linked to crown Lycopodiaceae, but the lack of well‐preserved material has hindered definitive recognition of this group in the paleobotanical record.New, exceptionally well‐preserved permineralized lycopsid fossils from the Early Cretaceous (125.6 ± 1.0 Ma) of Inner Mongolia, China, were examined in detail using acetate peel and micro‐computed tomography techniques. The anatomy of extant Lycopodiaceae was analyzed for comparison using fluorescence microscopy. Phylogenetic relationships of the new fossil to extant Lycopodiaceae were evaluated using parsimony and maximum likelihood analyses.Lycopodicaulis oellgaardiigen. et sp. nov. provides the earliest unequivocal and best‐documented evidence of crown Lycopodiaceae and Lycopodioideae, based on anatomically‐preserved fossil material.Recognition ofLycopodicaulisin Asia during the Early Cretaceous indicates the presence of crown Lycopodiaceae at this time, and striking similarities of stem anatomy with extant species provide a framework for the understanding of the interaction of branching and vascular anatomy in crown‐group lycopsids.
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- Award ID(s):
- 1748286
- PAR ID:
- 10446422
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 233
- Issue:
- 5
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 2310-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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