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Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

More than 800 permineralized fagaceous fruits have been studied from the Eocene Appian Way locality of Vancouver Island, British Columbia. These cupulate nuts are the most common fruits preserved at the locality. They occur in calcareous concretions and were studied using the cellulose acetate peel technique. Cupules are borne on a spiny stalk and are broadly ovate in both longitudinal and transverse section. Cupules are evalvate and have both branching and simple spines. A single, ovoid, sclerotic nut is enclosed entirely by the cupule, except at the apex, where a stylar protrusion is free from any surrounding tissues. The nut is bilocular with a glabrous endocarp lining. At maturity, a single seed occupies the locular cavity. The embryo is straight and no endosperm is evident. The single-fruited, spiny cupule is most similar to fruits of Fagaceae subfamily Castaneoideae. Bicarpellate fruits and a glabrous endocarp place them within the fossil genus Cascadiacarpa; however, they differ from Cascadiacarpa spinosa in nut wall anatomy, cupule ornamentation, shape, and size. Fruits of Cascadiacarpa exilis sp. nov. are compared with spiny, small compression and impression fossil fruits from the Eocene Taneum Creek locality of Washington State. The characters of the Washington State fossils overlap with those observed in the anatomically preserved Appian Way cupulate fruits and, as such, may represent compression and impression fossils of the same genus. The permineralized fruits document that evalvate, spiny, cupulate nuts of Fagaceae were present and common in the Eocene of western North America. [ABSTRACT FROM AUTHOR]

In addition to having a rich assemblage of mammalian fossils, the Gao Mine locality in the Paskapoo Formation of south-central Alberta has yielded numerous plant specimens of late Paleocene (late Tiffanian or Ti5) age. The plant fossils are preserved in siltstones and fine-grained sandstones interpreted as overbank sediments that were deposited on an aggrading floodplain. The assemblage is dominated by the cupressaceous conifer Metasequoia foxii and the cercidiphyllaceous dicot Joffrea speirsiae, including their well-preserved seedlings. The flora also contains foliage of the ferns Onoclea and Speirseopteris and the woody dicots Palaeocarpinus, Aphananthe/ Celtis , Aesculus, Beringiaphyllum, ? Trochodendron, and Wardiaphyllum, as well as seedlings of unknown dicotyledonous angiosperms. Metasequoia foxii and Speirseopteris are unique to the floras of Gao Mine and the nearby Munce's Hill site (Tiffanian Ti4). The remainder of the taxa are common in late Paleocene floras of North Dakota, Montana, and Wyoming, all USA. The floras of the nearby Joffre Bridge Roadcut and Blindman River sites (both Tiffanian Ti3) are more diverse, but both of those sites encompass a wider range of depositional environments and may include higher percentages of allochthonous material. Most of the Gao Mine material is autochthonous. The seedlings were buried in place, along with the surrounding leaf litter, preserving a record of the local plant community. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Relationships of living and fossil Pinaceae were inferred using parsimony and Bayesian inference of morphological characters and plastid and nuclear DNA sequences. When considering extant taxa only, adding molecular to morphological characters resulted in markedly increased resolution and branch support compared with analysis of morphology alone. Including 45 fossil taxa resulted in drastically decreased resolution in morphology-based consensus trees. We evaluated the effect on branch support and resolution of including DNA sequences, deleting fossils lacking information for cone scale apices and seeds, using reduced consensus methods, and using implied weighting, and found that the greatest improvements were found by including DNA sequences and using implied weighting. The tree topologies from parsimony and Bayesian inference confirm previous findings that the fossil genus Pseudoaraucaria and a few species of Pityostrobus from the Lower Cretaceous are related to abietoid genera, and that other species of Pityostrobus are pinoid and closely related to Pinus. Focusing phylogenetic analyses on the most complete fossil cones, specifically those that are anatomically preserved and include both cone scale apices and seeds, and taking into account homoplasy, resulted in the clearest hypotheses for the timing and sequence of diversification in the family. [ABSTRACT FROM AUTHOR]