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Sixty-seven coalified compression specimens of leaves, one attached to a stem, have been found in the St. Mary River Formation (uppermost Campanian–lowermost Maastrichtian, Upper Cretaceous) near Cardston, Alberta, Canada. Leaves have long multi-veined petioles with clasping bases, and an ellipsoid to obovate lamina with a convex to almost flat apex, and a crenate margin with one order of convex-convex chloranthoid teeth with angular sinuses. Tooth apices often end in a small concavity interpreted as a hydathode. Several primary veins enter the lamina in a flabellate manner. The central primary vein branches pinnately while lateral primaries, dichotomize toward the margin producing a reticulodromous pattern of secondaries. Secondaries arising from the lateral primary veins are the result of consistent dichotomies and anastomoses with a concurrent loss of gauge. Tertiary veins are alternate percurrent, and quaternaries form an irregular reticulate fabric. Quaternary veins form polygonal areoles with freely ending veinlets. Some specimens show a polygonal pattern of sub-epidermal aerenchyma like that of many other aquatics. Plants are compared to other fossil aquatic taxa, including those from the St. Mary River Formation and extant members of Ranunculaceae, Menyanthaceae and Nymphaeaceae. The specimens are described as a new amphibious aquatic: Zlatkovia crenulata Rothwell & Stockey gen. et sp. nov., eudicot family incertae sedis. This assemblage meaningfully enriches our understanding of aquatic and adjacent wetland habitats near the close of the Cretaceous, and emphasizes that the structure of modern wetland communities was well established before the end of the Mesozoic. [ABSTRACT FROM AUTHOR]

Abstract: A single, permineralized ascoma resembling a pseudothecium assignable to the Pleosporales is described from the Eocene Appian Way fossil locality on Vancouver Island, British Columbia. The ascoma is globose, ostiolate, and erumpent on a fragment of the bark from an unidentified seed plant. Basally arranged asci contain large, multicelled, obovate ascospores within a single cavity or locule enclosed by a two-layered pseudoparenchymatous tissue that ostensibly represents ascostroma. Given this interpretation of the specimen''s morphological features, Margaretbarromyces dictyosporus gen. sp. nov. represents the first report of a corticolous pleosporalean ascoma in the fossil record. [Copyright &y& Elsevier]

Reinvestigation of a Late Cretaceous plant assemblage from along the Colville River on the North Slope of Alaska reveals both that the flora is far more diverse than previously suspected, and that many specimens are anatomically preserved. The flora includes one moss, an osmundaceous fern, one species of Ginkgo , the putative conifer leaf Pityophyllum , five species of cupressaceous conifers, five dicot leaf morphotypes, and one monocot. The cupressaceous remains heretofore have been interpreted as a single taxodioid/sequoioid conifer species, Parataxodium wigginsii Arnold and Lowther. However, reexamination of the fossils reveals five different morphologies of cupressaceous ovuliferous cones, and a wide range of intergrading leafy shoot morphologies. Peel sections show excellent internal anatomy for many of the cupressaceous conifer organs, as well the moss. These fossils characterize a high-latitude deciduous flora dominated by cupressoid conifer trees, with less common dicot and Ginkgo trees, and with ground cover that includes osmundaceous ferns, monocots, and dicranalean mosses. The increased diversity of disarticulated plant parts in the assemblage demonstrates that Parataxodium wigginsii is not nearly as well understood as widely believed, and that the genus and species concepts as currently defined may be based on organs from several cupressaceous conifers. This assemblage is an outstanding example of an unusual Late Cretaceous, high-latitude, Northern Hemisphere, mixed dicot-coniferous, cool temperate, deciduous forest that existed in total darkness for a significant period each year. [ABSTRACT FROM AUTHOR]