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Premise of research. Ten anatomically preserved conifer seed cone specimens are preserved on the surfaces of, and within, three interlocking rock fragments of terrestrial limestone discovered as float along the Colville River on the North Slope of Alaska, providing additional evidence for the diversification of taiwanioid Cupressaceae during the Upper Cretaceous–Cenozoic interval. Methodology. Specimens on rock surfaces were measured and photographed, and then serial anatomical thin sections were prepared by the cellulose acetate peel technique. Three-dimensional images of selected specimens were also captured using micro–computed tomography (micro-CT). Pivotal results. The structure of these seed cones is similar to that of living Taiwania cryptomerioides in cone shape, the presence of subtending scalelike leaves, helically arranged and imbricating foliate ovuliferous complexes (OCs), the absence of a separate ovuliferous scale tip, variation in numbers of OCs, and by having two adaxially positioned winged seeds per complex. However, abruptly upturned OC, details of OC vasculature, and distinctive histological features reveal that these seed cones represent a new species of the extinct genus Mukawastrobus. Conclusions. When added to the existing record of fossil seed cones, the new species Mukawastrobus arnoldii highlights the recent discovery that among early-diverging lineages of Cupressaceae, there has been considerable Cretaceous, Paleogene, and Neogene evolution that is reflected by variations among subtle characters that are not recognizable in any but the most completely preserved specimens. [ABSTRACT FROM AUTHOR]

Premise of research. Early Cretaceous (Valanginian) rocks exposed at Apple Bay (Vancouver Island, Canada) have yielded numerous anatomically preserved bryophytes that have expanded our knowledge of the pre-Cenozoic fossil record of this group. A new moss type with tricostate leaves from Apple Bay combines characters not encountered in moss species recorded previously, warranting in-depth characterization of a new taxon. Methodology. Carbonate concretions containing permineralized fossil material were sectioned using the cellulose acetate peel technique. The resulting acetate peels providing serial sections through the bryophyte specimens were used to reconstruct the habit of the plant and its leaves in two and three dimensions. Pivotal results. We describe a new species of moss in the family Tricostaceae, Tricosta priapiana sp. nov. The anatomy and morphology of the new species justify expanding and refining the diagnoses of Tricostaceae and Tricosta , especially with respect to perigonial branches and the morphology of branch buds. The presence of pseudoparaphyllia surrounding the branch buds supports the pleurocarpous affinities proposed previously for the Tricostaceae. Conclusions. Tricosta priapiana adds to the diversity of tricostate mosses, an extinct group that was intriguingly diverse in the Mesozoic. Nevertheless, the tricostate state is probably a convergent trait, or a trait that may have evolved independently in acrocarpous and pleurocarpous moss lineages in response to similar selective pressures. Still, it remains unclear what such selective pressures may have been, as the paleoclimates and habitats that hosted the tricostate mosses are not well circumscribed, precluding comparisons among the different species and their closest analogs among living multicostate mosses. [ABSTRACT FROM AUTHOR]

Premise of research. Two permineralized inflorescences have been found in calcium carbonate concretions from the Eocene Appian Way locality on Vancouver Island, British Columbia, increasing sampling density and helping clarify the pattern of phylogeny for Alismatalean monocots. Methodology. Serial sections of specimens were prepared by the cellulose acetate peel technique and studied with light microscopy. Phylogenetic analyses using a morphological matrix of living and fossil Araceae and Acoraceae were performed using TNT version 1.5 to help establish relationships of the fossil inflorescences. Pivotal results. Inflorescences are cylindrical spikes, >37 mm long and 8.1 mm wide, with a peduncle at least 14.5 mm long, bearing numerous helically arranged, bisexual sessile flowers with hooded tepals. Fruits are trilocular, with basal axile placentation and one seed per locule. Remnants of probable stamens are present in most flowers. Conclusions. Flower structure was compared to those of other petalloid, spicate, bisexual flowers in the monocot families Acoraceae and Araceae (Alismatales). The number of carpels is similar to that in Acorus (Acoraceae) and Spathiphyllum (Araceae, Monsteroideae) and some Pothoideae. Single-seeded ovaries are common in Araceae, while the locules in Acorus contain several apically attached seeds. Phylogenetic analyses place Appianospadix in Proto-Araceae near the base of the aroid tree. This inflorescence with a unique combination of characters is described as Appianospadix bogneri , a new genus and species of Alismatales (family: Araceae). [ABSTRACT FROM AUTHOR]

Premise of research. Numerous large permineralized fossil seeds from the Jurassic of Haida Gwaii, western Canada, provide evidence for the mode and tempo of cycad evolution. Methodology. Fossil seed specimens are studied from external morphology and serially sectioned by the classic cellulose acetate peel technique to reveal anatomical features of the integument, vascular system, nucellus, and gametophyte. Fossils are compared to living cycad seeds that are also examined from external views, dissections, and anatomical preparations. Pivotal results. The fossil seeds are described as Traskia maahlae gen. et sp. nov. Features of the integument and vascular system reveal that T. maahlae is a stem group cycad that shares seed architecture and mode of germination with living Cycas spp. Conclusions. Traskia maahlae adds to a growing body of paleontological data on stem and crown group cycads. Results suggest that modern pollination and postpollination biology and the two contrasting modes of cycad seed germination evolved during the Mesozoic but that crown group cycad species may not have appeared until the Cenozoic. [ABSTRACT FROM AUTHOR]

Premise of research. The Late Cretaceous Yezo Group in Hokkaido, Japan, yields abundant plant debris in calcareous concretions. Nearly 150 species of plants have been described since 1910. Here we add a new genus of a probable stem polypodioid leptosporangiate fern to the plants of the Yezo Group based on a permineralized fertile pinnule from the Mikasa locality. Methodology. The fertile pinnule was detected in a calcareous concretion as an X-ray computed tomography image. Specimens were studied from serial cellulose acetate peels. Three-dimensional reconstructions of the entire pinnule and the soral, sporangial, and indusial morphologies were rendered using Molcer Plus and Amira. Pivotal results. The pinnule is 11.7 mm long, less than 7 mm wide, and deeply pinnatisect, with an abaxially grooved midrib or "costule" bearing one terminal and six lateral segments with catadromic pinnate venation. Lateral veins are simple or bifurcate once near the segment margin. The sorus is indusiate and abaxial and occurs slightly proximal to the end of the single vein or, when the lateral vein bifurcates, near the end of a much shorter anadromic vein. The indusium is reniform, is attached close to a massive receptacle only at its base, and is not laterally fused with the lamina. Approximately 17 sporangia with a slightly oblique, incomplete annulus, each estimated to contain ca. 64 spores, are formed per sorus. Spores are tetrahedral and trilete, have a triangular amb and slightly convex sides, are 42–45 μm in equatorial diameter, have a smooth exine, and are comparable to Biretisporites -type dispersed spores. Conclusions. The unique characters of the fossil are shared separately by extant basal polypods, most abundantly in Dennstaedtiaceae. However, the oblique annulus of the fossil does not occur in any extant members of Polypodiales unless it appears homoplastically. We therefore describe the fossil as a new taxon of a probable stem polypod, Mikasapteris rothwellii gen. et sp. nov., without any order and family assignments. The presence of Mikasapteris during the Late Cretaceous shows that pre-Polypodiales ferns were more diverse during this period. [ABSTRACT FROM AUTHOR]

Premise of research. Sixteen compression/impression specimens of a new floating aquatic angiosperm that enrich our knowledge of Late Cretaceous vegetation have been identified from the early Maastrichtian St. Mary River Formation near Cardston, Alberta, Canada. Methodology. Fossils were studied using dégagement and photographed under reflected light. Leaves were morphotyped using methodology in the Manual of Leaf Architecture and compared to other extant and extinct rosette-forming floating aquatic angiosperms. Pivotal results. Stems of this aquatic dicot show determinate growth of floating shoots with opposite/decussate attachment of heterophyllous leaves. Leaves are simple and sessile at the apicalmost node, simple and petiolate at the second node, and compound with three leaflets at nodes 3–6. Compound leaves are petiolate and ternate (trifoliate). Leaflet shape is unlobed, obovate, and symmetrical; base is acute-obtuse; apex angle is obtuse; base shape is convex; petiolar attachment is marginal; apex shape is rounded; and margin is crenate. Primary veins are flabellate to pinnate with three to five basal veins that dichotomize distally. Secondary veins are craspedodromous with uniform spacing and angles. Teeth are of a single order, three per centimeter near apex, and convex-convex; the sinus is angular, and the apex is foraminate. Conclusions. While the basic growth habit of this plant is similar to that of several extant taxa in the Onagraceae, Lythraceae, Plantaginaceae, and Hydrocharitaceae, leaf venation and the presence of compound leaves differ greatly from the living species. In growth habit and the presence of both simple and compound leaves, the new plant is similar to Quereuxia angulata , also found at this fossil site. These fossils are described as a new genus and species, Tolmania aquatica Edmonds, Stockey & Rothwell, which differs from Quereuxia in pattern of heterophylly, venation, larger plant size, stem morphology, and the presence of hydathodes in the leaves. [ABSTRACT FROM AUTHOR]

Premise of research. Mesozoic to Cenozoic fungi forming scutella, shield-like coverings of sporulating tissue on leaf surfaces, offer insights into the diversification of filamentous ascomycetes. We found a new fungal sporocarp type consisting of radiate scutella growing from the stomata of leaves of a conifer in a survey of dispersed plant cuticles from the Lower Cretaceous of Virginia. Here, we interpret the new morphotype and compare it with other fossil groups and with extant taxa. Methodology. We isolated fragments of conifer cuticles colonized by the fungus from macerated clays of the Potomac Group, lower Zone 1 (Aptian, 125–113 Ma), and studied them using light microscopy. We analyzed the anatomy of scutella of living taxa and compared the fossils with extant taxa producing either rhizothyria, asexual sporocarps that release spores from below the outer edge of the scutellum, or thyriothecia, sporocarps that release spores through dorsal cracks or an ostiole. Pivotal results. Stomatothyrium placocentrum gen. et sp. nov. has a radial arrangement of scutellum hyphae, characteristic of extant and fossil thyriothecial species in Dothideomycetes (Ascomycota). The scutella develop cracks on the dorsal surface that may show the dehiscence mechanism. Unusually for dehiscence in Dothideomycetes, the cracks follow the scutellum circumference rather than its radius. Each scutellum arises from a host plant stoma, appearing first as a hyphal columella that broadens into a flat scutellum disk on the leaf surface. The morphotype is common, and we found more than 63 specimens at different developmental stages on cuticle fragments. Conclusions. Its unique morphology suggests that S. placocentrum gen. et sp. nov. represents a now extinct group of leaf-dwelling Dothideomycetes that formed thyriothecia. This discovery contributes to our understanding of the range of character combinations of early epiphyllous Ascomycota. [ABSTRACT FROM AUTHOR]

Premise of research. A single cylindrical conifer seed cone has been discovered in a calcium carbonate marine concretion from the Upper Cretaceous Eden Main Quarry, dated as early Coniacian (∼89 Ma), 35 km northwest of Courtenay on Vancouver Island, British Columbia, Canada. Methodology. The specimen was sectioned with a rock saw, and serial sections were prepared using the classical cellulose acetate peel technique. Peel sections were mounted on microscope slides. Reconstructions of the cone and seeds were rendered with Avizo. Pivotal results. The cone is somewhat abraded, at least 2.3 cm long and 1 cm wide, with the apex missing and most of the base coalified. The well-preserved midsection shows bract/scale complexes inserted at a steep angle. The bract/scale complex has a central rhomboidal shaft and two lateral winglike extensions. Xylem of the cone axis is robust, with secondary xylem tracheids that have circular-bordered pits. A single circular vascular trace enters the bract/scale complex. Three resin canals enter the base of the scale and divide to form up to eight or nine canals distally. Six overlapping, inverted winged seeds, ∼8 mm long and 1 mm thick, with two large, fleshy wings are borne on the adaxial surface of each scale. The nucellus is free from the endotesta to its base. Megagametophytes and embryos occur in some seeds. Cells of the megagametophyte have granular contents. This cone shows similarities in overall structure and vasculature to those of living Taiwania (Cupressaceae); however, the fossil cone size is generally larger, with six seeds per scale versus two, and seeds are extremely large and fleshy with a unique submicropylar structure. Conclusions. This cone is compared with living and fossil taxa of Cupressaceae and described as Comoxostrobus rossii gen. et sp. nov. (Cupressaceae subfamily Taiwanioideae), revealing that taiwanioid Cupressaceae were much more diverse and widespread during the Cretaceous. [ABSTRACT FROM AUTHOR]

Premise of research. Five permineralized specimens of infructescences and dispersed fruits assignable to the Altingiaceae have been identified from the Late Cretaceous (Coniacian) Eden Main Quarry on Vancouver Island, British Columbia, Canada. Two infructescences and three isolated two-loculed fruits are preserved in calcium carbonate marine concretions. Methodology. Concretions were sectioned using the cellulose acetate peel technique and were included in a phylogenetic analysis employing morphological characters using TNT. Pivotal results. Infructescences are globose ca. 1 cm in diameter with at least 24 two-loculed fruits and a broad central axis. We have been unable to identify any perianth parts, but there are knob-like extrafloral processes similar to the phyllomes of other altingiaceous infructescences. The inner carpel lining consists of a single palisade layer of elongate rectangular cells. The endocarp also contains several layers of thick-walled, elongate sclerenchyma. The mesocarp is well differentiated, with fiber bundles interspersed with parenchyma and resin canals. There are at least 16 seeds (ovules) per carpel with axile placentation, but most of these are immature or aborted. Fruits have septicidal and ventricidal dehiscence. Specimens are assigned to Protoaltingia comoxense Scharfstein, Stockey & Rothwell gen. et. sp. nov. Conclusions. These fossils represent the second-most ancient occurrence of Altingiaceae, and phylogenetic analysis of morphological characters confirms that P. comoxense is most similar to species of Altingia. Results of morphological analyses resolve Altingia and Liquidambar as sister clades, placing P. comoxense as the basal member of the Altingia clade and sister to Altingia spp., thus documenting that evolutionary diversification of the core eudicot family Altingiaceae (Saxifragales) was well underway by the mid–Upper Cretaceous. [ABSTRACT FROM AUTHOR]

Premise of research. Four small pollen cones bearing pollen have been found attached to a leafy twig in a calcareous concretion from the Valanginian Apple Bay locality, northern Vancouver Island, British Columbia, increasing the known morphological diversity of Early Cretaceous cupressaceous pollen cones.Methodology. Specimens were prepared using the cellulose acetate peel technique, pollen was examined using SEM, and three-dimensional reconstructions were rendered with Avizo.Pivotal results. The small, subglobose cones bear helically arranged microsporophylls with a central resin canal. Each sporophyll bears three abaxial pollen sacs. Walls of pollen sacs are comprised of radially elongated rectangular cells with prominent wall thickenings. Most pollen sacs are intact and contain numerous, nonsaccate pollen grains. Pollen is 16-24 μm in diameter with one exit papilla that forms a low protuberance on the grain. External surfaces of grains are scabrate with numerous orbicules and macrogranules, and the nexine is laminated. Cone and pollen morphology most closely resemble taxa of the taxodioid Cupressaceae. The number of pollen sacs per microsporophyll is similar to Athrotaxis, Metasequoia, Sequoia, Sequoiadendron, and the Paleogene fossil conifer Homalcoia. Arrangement of cones on branches differs from those of Athrotaxis, Metasequoia, and Homalcoia; pollen lacks the long distal papilla of Sequoia and Sequoiadendron and is most similar in size to that in some cupressoid Cupressaceae in Chamaecyparis, Thuja, and Juniperus but with a smaller aperture.Conclusions. This combination of features is unlike that found in any living or extinct species of Cupressaceae. The fossil species is described as Morinostrobus holbergensis gen. et sp. nov., furthering our understanding of character evolution within Cupressaceae s.l. and adding to the evidence that the Lower Cretaceous was a time of increasing cupressaceous diversity. [ABSTRACT FROM AUTHOR]

Premise of research. Two permineralized fruits have been found within a single calcareous concretion from the Upper Cretaceous (upper Campanian) Spray Formation of Vancouver Island, British Columbia. These fossils provide additional evidence for the initial phylogenetic diversification of Cornales, the earliest diverging asterid lineage. Methodology. Specimens were prepared using the cellulose acetate peel technique. Pivotal results. A new cornalean species, Suciacarpa xiangae sp. nov., is characterized on the basis of a wellpreserved fruit specimen. This fruit is represented by a large ovoid tetralocular sclerenchymatous endocarp. Locules are crescent shaped in transverse section and accompanied by short dorsal germination valves. Valves consist of small isodiametric sclereids as well as a large number of large secretory cavities. The septum and central axis are composed of transversely oriented and interwoven fibers and elongate sclereids. There is no major central vascular bundle; however, there are numerous small bundles scattered within the septa. This fruit has one apically attached seed per locule. An additional cornalean taxon--Sheltercarpa vancouverensis gen. et sp. nov., also represented by a single smooth tetralocular sclerenchymatous endocarp--consists of isodiametric and a few elongate sclereids, with short germination valves, one seed per locule, and lacks a central vascular bundle. Conclusions. Because of unique combinations of characters, the two fruits described in this study represent two new cornalean taxa, S. xiangae sp. nov. and S. vancouverensis gen. et sp. nov. These fruits display mosaics of apomorphic and plesiomorphic characters that occur in families of at least two different major cornalean clades: Cornaceae/Alangiaceae and Nyssaceae/Mastixiaceae/Davidiaceae. The morphological diversity seen in these taxa and other cornaleans from the Late Cretaceous suggests that the Campanian was an important time for the initial phylogenetic diversification of Cornales. [ABSTRACT FROM AUTHOR]

Premise of research. Despite an increase in interest in the fossil record of bryophytes (i.e., liverworts, hornworts, and mosses), the biology and taxonomy of these organisms remain understudied and, at times, elusive. In the pre-Cenozoic, especially, few taxonomically informative moss fossils are known. From this perspective, the anatomically preserved Apple Bay flora of Vancouver Island holds a wealth of Cretaceous moss diversity that, until very recently, has remained unexplored. Methodology. Fossils are preserved anatomically in carbonate concretions and studied in serial sections prepared using the cellulose acetate peel technique. Pivotal results. Krassiloviella limbelloides gen. et sp. nov., defined by tricostate homocostate leaves and much-branched stems, is a new addition to the pleurocarpous moss family Tricostaceae (superorder Hypnanae). Conclusions. Krassiloviella limbelloides is the second bryophyte described as a result of ongoing studies of the Early Cretaceous Apple Bay flora of Vancouver Island. Krassiloviella is also the second genus of family Tricostaceae, which provides the oldest unequivocal evidence for the pleurocarpous superorder Hypnanae and a hard minimum age for the group. Revealing aspects of diversity unaccounted for in extant floras, such fossil bryophyte discoveries emphasize the importance of paleontology for efforts aimed at documenting the history of biodiversity. [ABSTRACT FROM AUTHOR]

Premise of research. A large number of floating aquatic aroid fossils have been recovered from pond sediments in the Hell Creek Formation (Upper Cretaceous) of South Dakota, providing valuable new data about aquatic vegetation of the uppermost Cretaceous, that are used to describe a newspecies of the genus Cobbania, and to evaluate associated reproductive structures and phylogenetic relationships among floating aquatic monocots. Methodology. Fossils were uncovered as needed with fine needles to reveal surface features of the specimens. Images were captured with a digital scanning camera, and phylogenetic analyses were conducted with TNT implemented through WinClada. Pivotal results. The new species, Cobbania hickeyi Stockey, Rothwell & Johnson, extends the range of the genus to the uppermost Cretaceous, supports the taxonomic integrity of the genus Cobbania, and increases our understanding of structural variation and species richness within the genus. Associated reproductive structures include an aroid spadix, strengthening the assignment of Cobbania to the Araceae. Phylogenetic analyses using "total-evidence" data help resolve conflicting results from either morphological or nucleotide sequence analyses of relationships among floating aquatic aroids, and the fossil taxon Aquaephyllum does not nest among the other floating aquatic species in any of our results. Conclusions. Species of the genus Cobbania were an important component of aquatic vegetation across the Northern Hemisphere during the Late Cretaceous. In tests of competing hypotheses for relationships among Pistia stratiotes, Cobbania spp., and species of Araceae subfamily Lemnoideae, the results from a "total-evidence" analysis suggest that specializations for the floating aquatic life form may be overwhelming other characters in the results of morphological analyses alone. [ABSTRACT FROM AUTHOR]

Premise of research. A large pollen cone cluster attached to a cunninghamioid twig and surrounded by leaves has been identified from Eocene calcium carbonate marine concretions from the Appian Way locality on Vancouver Island, British Columbia, Canada. The cluster preserves 18 cones but probably bore at least 24 pollen cones based on cone placement in the cluster. Methodology. Specimens were studied using the cellulose acetate peel technique, and reconstructions were made with ImageJ visualization software. Pollen was examined using SEM. Pivotal results. Cones are helically arranged around the tip of an ultimate leafy branch that terminates in scale leaves, each showing a central resin canal. Vegetative leaves on the twig are amphistomatic, showing typical cunninghamioid anatomy, with a large central resin canal abaxial to the vascular bundle, an elongate zone of transfusion tissue, a nonplicate mesophyll, and a hypodermis three to four cells thick. Each pollen cone is produced in the axil of a bract and has three scale leaves surrounding the base of the cone axis. Individual pollen cones have helically arranged microsporophylls, each with three elongate abaxial pollen sacs. While the cones are immature, pollen sacs with pollen are present in several cones. The exine is scabrate, with numerous orbicules, and no papilla is evident. Conclusions. This cluster provides the first detailed anatomically preserved fossil evidence for the pollen cones of Cunninghamia. It shows a large number of similarities to the pollen cone clusters of extant Cunninghamia lanceolata and Cunninghamia konishii and the Late Cretaceous Cunninghamia taylorii, strengthening hypotheses for a basal position of cunninghamioids within the Cupressaceae and further demonstrating that some characters of Cunninghamia have remained relatively unchanged since at least the mid-Cretaceous. [ABSTRACT FROM AUTHOR]

Premise of research. Twenty-one permineralized fossil flowers assignable to Lauraceae from the Eocene Appian Way locality on Vancouver Island, British Columbia, Canada, provide important anatomical and morphological data for interpreting evolutionary patterns in this diverse magnoliid family. Methodology. Consecutive anatomical sections were prepared using the cellulose acetate peel technique. Morphology and anatomy of the flowers were determined from anatomical sections, and three-dimensional reconstructions were rendered from serial sections using the software Amira. Pivotal results. Fossil flowers with oil bodies, trichomes, pollen, ovary anatomy, and other characters have allowed for the reconstruction of actinomorphic, pedicellate, and trimerous flowers with tepals in two whorls adnate to a shallow hypanthium. Nine fertile stamens occur in three whorls, the innermost of which bears paired glandular appendages, and a fourth whorl of sagittate staminodes surrounds the carpel. Anthers are tetrasporangiate. Stamens of the two outer whorls have median pollen sacs that are shorter than the two marginal pollen sacs. Third-whorl stamens have median pollen sacs that are longer than the marginal pollen sacs. Anthers of the first and second whorls are introrse, while the third-whorl anthers are extrorse. The fossil flowers have diagnostic characters of Lauraceae and are compared to flowers of extinct and extant taxa. Conclusions. The Eocene floral remains are assigned to Tinaflora beardiae gen. et sp. nov. We infer some aspects of floral biology based on different stages of development preserved among the fossils. The combination of well-preserved floral organs and in situ pollen is rare in the fossil record, allowing T. beardiae to expand the diversity of lauraceous floral morphology and provide further evidence for an Eocene radiation of the family in Laurasia. [ABSTRACT FROM AUTHOR]

Premise of research. A new, morphologically distinct, anatomically preserved conifer assignable to the basal Cupressaceae, which was subject to arthropod infestation during life, has been discovered within a marine carbonate concretion from the Coniacian (Late Cretaceous) Eden Main locality of Vancouver Island, British Columbia. Methods. Specimens were studied from anatomical sections prepared using the classic cellulose acetate peel technique. Pivotal results. This plant, described as Acanthostrobus edenensis gen. et sp. nov., has helically arranged needle leaves and terminal seed cones composed of numerous helically arranged bract/scale complexes dominated by the bract. Both vegetative leaves and bracts display exceptionally long, narrow tips that may have been involved in predator deterrence. The seed cone has diminutive ovuliferous scales with free distal margins; bract/scale complexes bear two to four small, secondarily inverted ovules. Cone tissues contain arthropod feeding galleries surrounded by necrotic tissue and closing tissue (wound periderm) that proliferated throughout the specimen. Conclusions. The new plant is clearly attributable to basal Cupressaceae (Cunninghamioideae, Taiwanioi-deae, and Athrotaxoideae). While it shares features with extinct Jurassic and Cretaceous Cupressaceae, it exhibits a novel combination of characters that distinguishes it from previously described genera. This discovery expands our understanding of basal cupressaceous diversity and provides insight into conifer-animal interactions during the Cretaceous. [ABSTRACT FROM AUTHOR]

Premise of research. A distinctive new species of osmundaceous fern, based on a permineralized trunk from Lower Cretaceous deposits of Haida Gwaii (formerly the Queen Charlotte Islands) off the west coast of mainland Canada, provides additional data for addressing the Mesozoic diversity and the overall pattern of phy-logeny for osmundaceous filicalean ferns. Methodology. The specimen was cut into segments and studied from both external morphology and anatomical sections prepared by the cellulose acetate peel technique. Microscope slides of sections were examined, and images were captured under transmitted light. Pivotal results. The fossil represents a new species of Osmundacaulis, which is only the third Northern Hemisphere representative of this predominantly Southern Hemisphere genus. Conclusions. Osmundacaulis whittlesii sp. nov. increases the Northern Hemisphere diversity of Cretaceous Osmundaceae, thus providing new data about Mesozoic diversity of the clade, potential sister-group relationships of crown-group Osmundaceae, and the overall pattern of phylogeny for Osmundaceae. [ABSTRACT FROM AUTHOR]

Premise of research. Humiriaceae occupy predominantly Neotropical lowland rainforests, with only a single Old World species in western Africa. Molecular divergence time estimates suggest that the family might have originated during the middle Cretaceous; however, fossil occurrences are lacking prior to the Paleocene. Here we provide new fossil evidence that expands our understanding of the paleobiogeographic history and evolution of this family. Methodology. Fossil endocarps and wood were compared with extant relatives of the family. Transverse and longitudinal sections of fossil and modern fruits were studied anatomically and morphologically. Pivotal results. Fruits of the new species, Duckesia berryi sp. n., from the Oligocene of Pacific coastal Peru (ca. 30-28.5 Ma), provide the earliest fossil evidence of Duckesia--the genus is now confined to Amazonia. We also document the earliest fossil fruit record for Sacoglottis tertiaria, from the early Oligocene (ca. 33.9-28.4 Ma) of Puerto Rico, and a new occurrence of Vantanea cipaconensis fruits, from the late Miocene of Panama (ca. 9-8.5 Ma). The new fossil wood, Humiriaceoxylon ocuensis gen. et. sp. n., from the late Eocene (ca. 37.2-33.9 Ma) of Ocú, Panama, confirms that this family was represented by large trees anatomically consistent with the extant genera. Conclusions. Humiriaceae originated in the Neotropics, with the oldest-known occurrences being fruits of Lacunofructus cuatrecasana and wood of H. ocuensis from the late Eocene of Panama. The family was generically diverse and widely distributed geographically across northern South America and Central America by the early Miocene. The new fossils also provide further evidence of regional extinctions within the Neotropics; extirpation of particular genera from Central America, the Caribbean, and coastal Peru indicate that Neogene orogenic and climatic events had an important effect on the modern-day distribution of the family. [ABSTRACT FROM AUTHOR]

Premise of research. Anatomically preserved platanaceous inflorescences have been found in rocks of Late Cretaceous (Coniacian) age at the Eden Main locality on Vancouver Island, British Columbia, Canada. Methodology. Specimens occur in calcium carbonate concretions near the base of the Nanaimo Group (Comox Formation) and are studied with the cellulose acetate peel technique and SEM. Pivotal results. Inflorescences are small (<5 mm), pedunculate heads, with fewer than 30 ?flowers per inflorescence. Both bisexual and unisexual flowers are present on the same inflorescence. Elongate and overarching tepals enclose the developing gynoecium and androecium at early stages of development. More mature specimens have individual flowers with at least two whorls of tepals fused toward the base. Flowers have a whorl of five free stamens, each with short filaments and a sclerotic apical connective extension. In situ pollen is small, prolate, tricolpate, 11-13 μm in polar diameter, and 8-9 μm in equatorial diameter. In flowers where it can be observed, the staminal whorl encloses five short, conduplicate, glabrous carpels lacking differentiated styles but bearing broad, flat apices. The ovary of these carpels is occupied by a single ovule. Conclusions. While the Eden Main specimens display a five-parted gynoecial arrangement common in the pistillate flowers of other Cretaceous platanoids, Ambiplatanus washingtonensis gen. et sp. nov. provides the first fossil evidence of functional bisexuality in fossil Platanaceae. [ABSTRACT FROM AUTHOR]

Premise of research. The occurrence of six ovulate cones and six leafy branching systems, two of which show attachment of the ovulate cone, reveals a new cunninghamioid fossil conifer from the Cretaceous Apple Bay locality of Vancouver Island, Canada. This anatomically preserved plant expands our understanding of basal Cupressaceae in the fossil record. Methodology. Specimens were studied from anatomical sections prepared by the classic cellulose acetate peel technique. Pivotal results. Vegetative shoots have helically arranged Cunninghamia-like leaves with a single vascular bundle and one to three resin canals. Ovulate cones consist of numerous helically arranged bract/scale complexes with a large bract and a small ovuliferous scale with three separate tips. There are three inverted seeds/ ovules attached adaxially, immediately proximal to the free scale tips. Conclusions. This discovery reveals the presence of a new genus and species of basal Cupressaceae, Hubbardiastrobus cunninghamioides, in the Early Cretaceous (Valanginian; ~136 Ma) of the Northern Hemisphere. These data expand the species richness of fossil Cupressaceae and further document the Cretaceous evolutionary radiation of subfamily Cunninghamioideae. [ABSTRACT FROM AUTHOR]

Premise of research. A third genus of anatomically preserved conifer seed cones has been recognized from a Late Jurassic deposit in northeastern Scotland. This cone is described as Bancroftiastrobus digitata Rothwell, Mapes, Stockey et Hilton. Methodology. The cone was sectioned with the classic coal ball peel technique and studied and photographed with transmission light. Pivotal results. Bancroftiastrobus digitata is a cylindrical cone with large, helically arranged ovuliferous scales subtended by short bracts, each bract/scale complex bearing two unwinged inverted seeds on the adaxial surface of the ovuliferous scale. Ovuliferous scales have abaxial plications in the midregion and divide distally, forming up to nine free distal lobes that are vascularized and covered by a dense ramentum of trichomes. The cone axis forms a continuous woody cylinder that surrounds a parenchymatous pith. There are numerous resin canals in the cortex of the cone axis that extend into each bract/scale complex, both abaxial and adaxial to the vascular traces. Vascular tissue to the bract diverges as a prominent terete bundle that separates from the stele immediately below a large inverted-U-shaped scale trace. More distally, the scale trace flattens and divides into a single row of C-shaped woody bundles. Conclusions. This new genus provides additional evidence for the diversity of stem group conifers that lived during the interval when most crown group conifer families originated. The new species is reminiscent of both Sciadopityaceae and Pinaceae. However, like the three anatomically preserved species of Pararaucaria Wieland (Cheirolepidiaceae), this cone does not clearly conform to any family with living species. Rather, these taxa have novel combinations of characters that make fossils vital for resolving deep internal nodes of the seed plant tree and that help to resolve the overall pattern of phylogeny. [ABSTRACT FROM AUTHOR]

Premise of research. The lianoid habit is found in 125 extant plant families and is most diverse and abundant in structurally complex forests, such as tropical forests. A stem with lianoid anatomy is described from Cretaceous sediments of Hornby Island, British Columbia. Methodology. The stem segment, 2.5 cm in diameter and 2.8 cm long, was studied using the cellulose acetate peel technique and SEM. Anatomy was documented and compared to fossil and modern taxa. Pivotal results. The stem lacks distinct growth increments, and the fibrous wood is dissected by large (110 cells wide) rays. Wood is diffuse porous with mostly solitary vessels, rarely in tangential multiples (2- 4). Vessel elements have a mean tangential diameter of 198 mm and mean length of 527 µm, bearing medium to large, crowded, elliptical to flat-elliptical alternate pits. Axial parenchyma is diffuse and vessels are surrounded by vasicentric tracheids with alternate bordered pitting. Rays are homocellular and 12 cm tall. Phloem rays are dilated, protruding into the xylem rays; thick-walled ray cells contain prismatic crystals. Periderm is composed of thin-walled cells interspersed with sclerotic nests. Wood anatomy of the fossil shows the most similarity to that of lianas in the Menispermaceae, Lardizabalaceae, and Ranunculaceae. Conclusions. The Hornby Island stem represents a new taxon, Atli morinii gen. et sp. nov. (Ranunculales). This liana specimen expands our knowledge of Cretaceous biodiversity and points to the presence of structurally complex forests on Hornby Island in the Campanian. Anatomy of Atli and other Cretaceous liana stems combines characteristics of several families in Ranunculales, documenting past anatomical diversity and possible stem lineage mosaicism. The most diverse lianoid lineages currently known from the Cretaceous and Paleogene are early-divergent eudicots, particularly Ranunculales and Vitales that account for more than 50% of described lianoid species during this key time period of angiosperm diversification. [ABSTRACT FROM AUTHOR]

A fossil seed cone with characters that have been hypothesized as transitional to the origin of crown group gnetophytes has been discovered in Lower Cretaceous deposits on Vancouver Island, British Columbia, Canada. This cone, described as Protoephedrites eamesii gen. et sp. nov., provides the first anatomically preserved fossil evidence for the evolution of gnetophyte cones with seeds. The cone is a compound shoot system consisting of a primary axis with nodes that bear bracts and axillary fertile shoots in an opposite/decussate arrangement. The secondary fertile shoot axis produces one or two pairs of diminutive bracteoles and a pair of erect ovules in an opposite/decussate pattern. In contrast to crown group gnetophytes, bracteoles subtend rather than surround and enclose the ovules. Ovules have a single multiseriate integument that is adnate to the nucellus in the basal region and free distally. The micropylar tube is short with a thick integument, but it displays distinctive cells of the inner integumentary epidermis that are characteristic of gnetophyte seeds. Each seed produces a large pollen chamber with a uniseriate wall. Paired erect ovules conform to the pleisomorphic morphology previously hypothesized for Ephedra seed cones, thus supporting the proposal that ancestral gnetophyte seeds are borne terminally on oppositely arranged sporophylls. The combination of gnetophyte synapomorphies and putative pleisomorphic characters displayed by Protoephedrites broadens the known range of morphologies for the most ancient gnetophytes. Detailed comparisons to several species of Bennettitales confirm that there are fundamental structural differences separating the seeds of Gnetales from those of Bennettitales, support the hypothesis that the outer seed envelope evolved within the gnetophyte clade, and suggest that Bennettitales are not as closely related to Gnetales as hypothesized by some authors. [ABSTRACT FROM AUTHOR]

A cylindrical permineralized conifer seed cone has been identified from the Officer Member of the Trowbridge Formation, near Izee, in east-central Oregon. The cone is preserved in a Middle Jurassic (Callovian) marine calcium carbonate concretion, associated with araucarian seed cones, conifer twigs and wood, cycad seeds, fern rachides, and lycopodialean remains and was prepared by the cellulose acetate peel technique. The specimen is abraded, 2.8 cm long and 1.3 cm wide, and consists of a cone axis with helically arranged bract/scale complexes, with a large ovuliferous scale and a broad, flattened bract. The bract/scale trace arises as a cylindrical unit from the cone axis, in which the bract and scale traces are separated by ground tissue. The traces separate immediately in the cortex to form a crescent-shaped bract trace and a horseshoe-shaped scale trace with associated sclerenchyma bands that form two triangular bundles toward the distal end of the scale. Ovuliferous scale tissue covers one inverted seed per scale, forming a pocket that contains the seed. Seeds are attached at the chalaza to the inside of the pocket. Seed integuments have an outer epidermis of isodiametric cells with dark contents; one or two layers of palisade cells, occasionally appearing in I-beam configuration; and several inner layers of randomly arranged cells. The nucellus is adnate to the integument, to near the apex, where it forms a cellular mound of tissue. Cylindrical cones with helically arranged bract/scale complexes, bract and scale free to the base, one seed per scale enclosed in a pocket, and triangular sclerenchyma bands are characteristic of the genus Vararaucaria, which recently has been placed in the extinct conifer family Cheirolepidiaceae. This third species extends the known range of Pararaucaria from the Southern Hemisphere to the Northern Hemisphere and emphasizes that the association of araucarian and pararaucarian conifers extended over a wide geographic area during the Jurassic. [ABSTRACT FROM AUTHOR]

The discovery of 16 cylindrical conifer seed cones at the Estancia Vilán locality in the Late Jurassic Cañadön Calcáreo Formation of Chubut Province, Patagonia, Argentina, provides anatomically preserved specimens, allowing for the description of a second species of Pararaucaria (Cheirolepidiaceae). The new species, Pararaucaria delfueyoi, is similar in general features to the type species, Pararaucaria patagonica, but has a specifically diagnostic combination of characters that include cone size, seed number, features of histology, and seed size. Specimens are cylindrical with a narrow axis that bears helically arranged bract/scale complexes. The bract and scale diverge from the axis at ~90° and separate from each other almost immediately. The ovuliferous scale extends toward the margin of the cone and then arches over to enclose two inverted nonwinged seeds within a pocket of tissue. Although the specimens are abraded such that the distal regions of the ovuliferous scales are not preserved, this combination of morphological and histological characters allows for the assignment of P. delfueyoi to the Cheirolepidiaceae with confidence. The co-occurrence of this cone with an undescribed species of Araucaria extends the geographic and stratigraphic ranges of this association, which previously has been known only from the Middle Jurassic of Santa Cruz Province of Patagonia. This extends the knowledge of anatomical variation among seed cones of Cheirolepidiaceae and improves our understanding of homology relationships for conifer seed cone structures. [ABSTRACT FROM AUTHOR]

A perithecial ascomycete, Spataporthe taylori gen. et sp. nov., represented by >70 sporocarps is preserved by cellular permineralization in marine carbonate concretions dated at the Valanginian-Hauterivian boundary (Early Cretaceous) from Vancouver Island, British Columbia, Canada. The spheroid perithecia with lumina 330-470 µm wide and 220-320 µm high are densely distributed and entirely immersed in the tissues of a coniferous leaf. The perithecial wall consists of an outer layer of large pseudoparenchyma and an inner layer of thin filamentous nature. Perithecial necks are incompletely preserved due to taphonomic abrasion; they have a bell-shaped chamber at the base and a narrow channel, with longitudinally aligned hyphae above. The basal chamber of the neck is filled with a plug of pseudoparenchyma, which subsequently disintegrates to form a peripheral collar; periphyses are present on the basal chamber walls. A pseudoparenchymatous hymenium lines the bottom of perithecia. Asci are clavate, with thinly tapered bases, and small (30-47 µm long and 12-20 µm wide at tip), ornamented with minute papillae. They become detached from the hymenium to float freely in the perithecium. No unequivocal ascospores were found, although smaller units are present in some of the asci. The combination of immersed perithecia with complex wall structure and a well-defined hymenium, absence of paraphyses, and persistent, detachable inoperculate asci is consistent with order Diaporthales of class Sordariomycetes. The small clavate asci are comparable to those found in family Gnomoniaceae. Perithecioid ascomata are rare in the fossil record, and bona fide perithecia are known with certainty only from the Early Devonian Rhynie Chert and Cenozoic amber. Spataporthe taylori contributes a well-characterized Early Cretaceous occurrence, which is also the oldest to date, to the scarce fossil record of the Sordariomycetes and a second taxon to the fungal flora of the locality, which also includes a basidiomycete. As the oldest representative of the Diaporthales, Spataporthe provides a minimum age (136 Ma) for the order and a direct calibration point for studies of divergence times in the ascomycetes. [ABSTRACT FROM AUTHOR]

This study describes a specimen that extends the oldest fossil evidence of Pinus L. to the Early Cretaceous Wealden Formation of Yorkshire, UK (131--129 million years ago), and prompts a critical reevaluation of criteria that are employed to identify crown group genera of Pinaceae from anatomically preserved seed cones. The specimen, described as Pinus yorkshirensis sp. nov., is conical, 5 cm long, and 3.1 cm in maximum diameter. Bract/scale complexes are helically arranged and spreading. Vasculature of the axis forms a complete cylinder with few resin canals in the wood, and the inner cortex is dominated by large resin canals. Bracts are short, with two resin canals, and separate from the scale base laterally. Distally, the ovuliferous scales broaden and thicken to form a rhomboidal apophysis with a dorsal umbo, characters found only in the genus Pinus among living conifers. Resin canals enter the ovuliferous scale abaxial to the vascular tissue, which divides distally to form a row of adaxially convex bundles. A short interseminal ridge separates two inverted and winged seeds on the adaxial surface of the ovuliferous scale. Seeds contain megagametophyte tissue and polycotyledonary embryos. Numerical cladistic analysis of anatomically preserved seed cones yields a wellresolved phylogeny of crown and stem group Pinaceae that is roughly concordant with the results of analyses that include living species only. All of the included species of Pinus form a clade with three very Pinus-like species that currently are assigned to the stem genus Pityostrobus. These results call to question the utility of traditional methods for assigning fossil seed cones to Pinus, resolve relationships among stem and crown group genera, and highlight the unnatural circumscription of Pityostrobus. This suggests that some species of Pityostrobus may actually represent the genus Pinus, and it demonstrates that the evolutionary diversification of Pinaceae began earlier than previously recognized from fossil evidence. [ABSTRACT FROM AUTHOR]

The Eocene Princeton Chert locality of southern British Columbia, Canada, provides data to develop organismal concepts for several species of fossil plants, including the first extinct species of Pinaceae, Pinus arnoldii Miller . This new species concept is based on a combination of interconnected organs, common histological features, and patterns of association among isolated plant parts. These data expand our knowledge of P. arnoldii from a morphospecies of ovulate cones to an extinct species of pine that produces woody stems with five-needled fascicles of leaves; simple pollen cones with two abaxial pollen sacs per microsporophyll, containing bisaccate pollen grains; seed cones with inflated scale apices, dorsal umbos that do not bear mucros, and a thick-walled sclerotic outer cortex; and coralloid roots with ectomycorrhizal associations. Organs preserved at various stages of development provide evidence for numerous aspects of growth and reproductive biology, including pollination biology and seed cone development. Cladistic analyses of morphological and molecular characters demonstrate that the novel combination of characters displayed by P. arnoldii causes this extinct species to fall near the base of the Pinus L. tree, either as the sister to all living species of the subgenus Pinus or outside the subgenera that have been defined by extant species of Pinus. [ABSTRACT FROM AUTHOR]

A new species of extinct conifer plants, Emporia royalii sp. nov. Hernandez-Castillo, Stockey, Mapes et Rothwell (Emporiaceae: Voltziales), is described from the rich fossil biota of the Late Pennsylvanian, Hamilton Quarry, Kansas. This conifer has lateral plagiotropic branches with simple and forked leaves, "age-dependent heterophylly," simple pollen cones, and compound ovulate cones. Stems have an endarch eustele, dense wood, and secretory cells arranged in nests or plates in the pith. Leaves are amphistomatic with two adaxial stomatal bands and two longitudinal abaxial rows of stomata with numerous trichome bases. Pollen cones are simple and have helically arranged microsporophylls with adaxial pollen sacs. Prepollen is monolete and monosaccate (Potonieisporites Bharadwaj). Ovulate cones are compound with bilaterally symmetrical axillary dwarf shoots that bear up to 45 sterile scales and 1-2 sporophylls and occur in the axils of helically arranged bracts with forked tips. Ovules are inverted and winged and resemble those of Emporia lockardii and Emporia cryptica. Emporia royalii is compared to other Euramerican waichian Voltziales, and a summary of the Emporiaceae and evolution of Paleozoic conifers is given. This is the fifth species of extinct conifer plants to be reconstructed from the Hamilton Quarry, making it the only Paleozoic locality in the world with numerous conifers all of which have been characterized as complete or nearly complete plants. [ABSTRACT FROM AUTHOR]

A new plant concept for the extinct conifer species Emporia lockardii (Mapes & Rothwell) Mapes & Rothwell (Emporiaceae) is developed from fossils collected at the Late Pennsylvanian Hamilton Quarry, Kansas. Emporia lockardii has lateral plagiotropic branches with simple and forked leaves, simple pollen cones, and compound ovulate cones. Stems have an endarch eustele with dense wood surrounding a septate pith. Leaves display position-dependent heterophylly with forked leaves on penultimate shoots and simple leaves on ultimate shoots. All leaves are amphistomatic with two stomatal bands and papillate epidermal cells on the adaxial surface and two basal stomatal bands and numerous trichome bases on the abaxial surface. Pollen cones are simple and have helically arranged microsporophylls and adaxial pollen sacs. Prepollen is monolete and monosaccate, and it conforms to the sporae dispersae genus Potonieisporites Bharadwaj. Ovulate cones are compound with helically arranged, forked bracts that subtend bilaterally symmetrical, axillary dwarf shoots with one to three narrow megasporophylls interspersed among numerous sterile scales. Ovules are terminal, inverted, and bilaterally symmetrical. This new reconstruction together with additional conifer reconstructions from the Hamilton Quarry locality indicate that the genus Emporia has a particularly high species diversity for walchian conifers. These findings support previous hypotheses that propose drier habitats as sites for the first appearances of plants that become dominant during the late Permian and Mesozoic. [ABSTRACT FROM AUTHOR]

Sixty trigonal fagaceous fruits have been identified in the calcareous nodules from the Eocene Appian Way locality of Vancouver Island, British Columbia, Canada. The anatomically preserved fruits are known at various developmental stages. In transverse section, fruits are triangular, with lateral ridges that vary in shape from rounded to sharply angled. In longitudinal section, the nuts show a broad base and a tapered apex. The ovary is partitioned into three locules at the apex, and placentation is axile, with two ovules per locule. Locules merge near the base, giving the appearance of a three-lobed ovarian cavity. This area is occupied by a single seed at maturity. The inner wall of the endocarp is tomentose. Major vascular bundles in the mesocarp occur midway between and at the lateral ridges of the nut. The nut is wingless and has an exocarp of dense sclerenchyma interrupted at the ridges by dehiscence lines that traverse the entire fruit wall. The nut surface is glabrous, except near the distal end, where trichomes emerge in proximity to three styles and surrounding perianth remnants. These nuts are assigned to the genus Fagus L. and represent the first permineralized Fagaceae of subfamily Fagoideae in the fossil record. Fagus schofieldii sp. nov. provides the earliest evidence of winglessness in Fagoideae and supports the possibility of a North American origin for the genus. [ABSTRACT FROM AUTHOR]

Twenty-six permineralized icacinaceous fruits have been identified in the calcareous nodules from the Eocene Appian Way locality on Vancouver Island. Specimens of three fruit types were studied using the cellulose acetate peel technique and three-dimensional computer-animated reconstructions. Fruits are drupes with thin exocarp and mesocarp and a distinctly pitted endocarp with ''tubercles.'' Endocarps are unilocular and bilaterally symmetrical, with straight-walled (cylindrical) to conical protrusions into the locule cavity. The outer layer of the endocarp in all fruits is composed of thick-walled interlocking digitate sclereids. The largest fruits are at least 19:5 3 12x5 mm, with a ridged external endocarp surface and two distinct endocarp layers, the inner one of which is papillate. The smaller fruits are 7:2 3 5x3 mm and have a smooth surface, a thinner threelayered endocarp, and a papillate locule lining. Intermediate-sized fruits, at least 9.8 mm long and 7.5-11.0 mm wide, are smooth externally, with a two-layered endocarp, the inner one of which is papillate. These fruits are compared anatomically to Palaeophytocrene from the North American Clarno nut beds and European London Clay flora. The presence of papillate cells lining the locule cavity, an overlooked character, has been documented for fruits of Palaeophytocrene from all sites. The intermediate-sized Appian Way fruits are most similar to Palaeophytocrene pseudopersica Scott emend. Manchester, while the other two fruit types differ from previously known taxa and are described as new species, Palaeophytocrene vancouverensis sp. nov. and Palaeophytocrene manchesteri sp. nov. The AppianWay fruits are assigned to Icacinaceae s.s. and are most like those of the Icacina group, the clade that contains Phytocrene, Pyrenacantha, Miquelia, Chlamydocarya, and Polycephalium. [ABSTRACT FROM AUTHOR]

An apparently exindusiate filicalean fern with radial sori, sporangia with a vertical annulus, and monolete spores occurs in Paleocene sediments ca. 57 million years old of central Alberta, Canada. Specimens are preserved as coalified compressions and show features of frond morphology and venation, sporangium morphology and dehiscence mechanism, number of spores per sporangium, and spore fine structure. Fronds have a deltoid blade region and are pinnate + pinnatifid, with fertile pinnules ranging to slightly smaller than vegetative pinnules and with simpler venation. Venation is open, with each lobe of the pinnatifid pinnule having a midvein from which laterals diverge in an alternate pattern. Laterals of vegetative pinnule lobes fork once and terminate at the margin, whereas those of fertile pinnule lobes are unbranched. Sori are round with numerous sporangia and are positioned under a vein. Each sporangium has a vertical annulus that is not interrupted by the stalk and produces ca. 64 spores. Spores are bean shaped and monolete, measuring 26-36 μm long, with exospore that is dense and sculptured by minute scabrae. Perispore is not preserved. This fern, named Speirseopteris orbiculata gen. et sp. nov., displays characters that are diagnostic of the highly derived filicalean families and is assigned to the Thelypteridaceae. To a lesser extent, it also resembles the Dryopteridaceae, emphasizing that modern fern genera existed among many extinct genera during the late Cretaceous and Paleogene. [ABSTRACT FROM AUTHOR]

A permineralized gleicheniaceous rhizome with an attached stipe base has been identified from the Appian Way locality on Vancouver Island, British Columbia, Canada. The specimens are preserved in Middle Eocene marine calcareous concretions that are studied using the cellulose acetate peel technique. The marginally mesarch rhizome has a vitalized protostele, protoxylem elements with helical wall thickenings, and scalariform metaxylem tracheids that occur in clusters. A continuous band of phloem and pericycle surrounds the xylem. The inner cortex consists of a layer of small-diameter sclerenchyma fibers, and the outer cortex is composed of larger parenchyma cells. A nodal island of sclerenchyma is present between the leaf trace and protostele at the level of frond-trace divergence. Long metaxylem tracheids in the frond trace show septa in longitudinal section that likely represent tyloses. Roots diverge from all sides of the rhizome with traces that run obliquely through the cortex. Numerous associated but isolated frond segments are found in the AppianWay nodules that show a pinched and inrolled C-shaped vascular trace and pseudodichotomous bifurcation. The frond traces have numerous protoxylem strands, and the general anatomy is comparable to that of gleicheniaceous stipes. The rhizome is described as a new species of Gleichenia, Gleichenia appianensis Mindell, Stockey, Rothwell, et Beard sp. nov., and represents the first record of Gleicheniaceae in the Tertiary of North America. [ABSTRACT FROM AUTHOR]

Anatomically preserved foliage of a dipteridaceous fern has been identified in both calcareous nodules and fine-grained, carbonate-cemented sandstone from the early Cretaceous (Hauterivian-Barremian) Apple Bay locality from Vancouver Island, British Columbia, Canada. Fronds with attached sporangia containing spores are preserved as both compression/impressions and as permineralizations. Fan-shaped laminar segments display paired teeth along the margin. Major veins dichotomize to the lamina edge, and finer veins reticulate, forming square to polygonal areoles, with freely ending veinlets. Veins are enclosed by sclerenchymatous sheaths, and the abaxial epidermis is recessed, producing concave areas between veins. Adaxial cuticle is thick, and the epidermis contains rectangular cells with undulating walls. Anomocytic scattered stomata occur on the abaxial surface. Sporangia and trichomes are scattered across the abaxial epidermis in the areolar concavities. Sporangial stalks are short, two to three cells long and four to six cells wide throughout their length. Sporangia have a vertical annulus that is interrupted by the stalk, and they contain trilete spores that correspond to Cibotiumspora jurienensis. Leaf morphology is similar to that of extant Dipteris novoguineensis and fossil Hausmannia spp. A unique combination of characters demonstrates that Hausmannia is a distinct genus of fossil dipterids. An examination of leaves from extant Dipteris rhizomes of various ages suggests that the genus Protorhipis may represent juvenile Hausmannia at some localities. The association of Hausmannia with small pieces of delicate moss gametophytes, fern sporelings, and vegetative remains of Lycopodium and Selaginella at Apple Bay reinforces the interpretation that these fossil dipterids were deposited under storm conditions and that Hausmannia may have grown in disturbed habitats. [ABSTRACT FROM AUTHOR]

The Lower Cretaceous (Valanginian to Hauterivian) Apple Bay locality on Vancouver Island, British Columbia, has yielded several fragments of fertile permineralized osmundaceous pinnae. Specimens are preserved in calcareous concretions, showing both internal anatomy and allowing for the reconstruction of external morphology. Sporangia are borne laterally and clustered along terete pinna segments. They range from 550 to 650mm in diameter, with a lateral annulus that is nine to 12 cells wide and two to three cells high and is separated from the stalk by only one or two cells. Spores are spheroidal and trilete, 40-52 mm in diameter, with long laesurae and a coarsely tuberculate exospore. Some tubercles are fused, forming microrugulae. Sporangial structure and spores most closely resemble those of Osmunda L. These fossils, described as Osmunda vancouverensis sp. nov., add to our growing appreciation for the antiquity of modern Osmundaceae and underscore the potential of the numerous well-preserved fern fossils from Apple Bay to enhance our understanding of the phylogeny of Filicales. [ABSTRACT FROM AUTHOR]

Trawetsia princetonensis Smith, Stockey, Nishida & Rothwell gen. et sp. nov. is described from several permineralized rhizomes, stipes, and higher-order frond members of a blechnoid fern that have been identified from the Middle Eocene Princeton Chert of British Columbia. Rhizomes bear stipes arising from all sides of the stem as well as diarch adventitious roots. The dictyostelic rhizomes are up to 16 mm across and have five to seven amphiphloic cauline bundles that are capped internally and externally by sclerenchyma. Ground tissue, where well preserved, is transitional from arenchymatous toparenchymatous, with abundant small sclerotic nests found throughout the pith and cortex. Multicellular scales are borne on the rhizome but are sparse and do not imbricate. At least three orders of frond material are preserved: stipes, primary pinnae, and laminar pinnules. Stipes have an adaxial groove, two adaxial hippocampiform bundles, and seven or fewer small, circular bundles arranged in an abaxial U-shaped arc. In distal sections of the rachis, the vascular bundles are reduced to three or fewer. Ground tissue of the stipe has sclerenchyma nests near the base but distally becomes completely aerenchymatous, further evidence that the Princeton Chert preserves an ancient wetland environment. This fossil material expands our knowledge of fern diversity from the Princeton Chert locality, which also includes osmundaceous, dennstaedtioid, and dryopterid ferns, and it contributes to the understanding of the timing and evolution of derived Filicales. While the vegetative anatomy of this fern allies it with the Blechnaceae, the lack of attached fertile fronds precludes the possible recognition of T. princetonensis as a fossil representative of a modern genus or perhaps even a living species. [ABSTRACT FROM AUTHOR]

An anatomically preserved leptosporangiate filicalean that combines characters of the Pteridaceae and tree ferns has been discovered in the Lower Cretaceous (Valanginian-Hauterivian boundary) Apple Bay flora on Vancouver Island, Canada. Exindusiate sori are radial, with numerous annulate sporangia diverging from a conical receptacle that is positioned below a pinnule vein. No paraphyses or other trichomes are present. Sporangia have a nearly vertical annulus that is not interrupted by the long, quadriseriate stalk. Spores are trilete and angular, with a distinctive equatorial flange and a distal deltoid structure that contacts the rim at the corners of the spore. The suture extends three-fourths of the distance to the margin and is flanked by prominent ridges. Spore walls consist of two dense layers, and the surface is psilate. Pterisorus radiata gen. et sp. nov. has characters that are reminiscent of both tree ferns and the most highly derived of modern species, providing direct evidence for the third major radiation of Filicales. [ABSTRACT FROM AUTHOR]

The discovery of two anatomically preserved rhizomes with attached stipe bases and adventitious roots contributes to our knowledge of filicalean fern diversity and evolution. Specimens are preserved in marine carbonate nodules at the Lower Cretaceous (Valanginian to Hauterivian) Apple Bay locality on Vancouver Island, British Columbia, Canada. They represent a previously unknown filicalean fern with transitional solenostelic-dictyostelic stelar architecture and are described as Stramineopteris aureopilosus gen. et sp. nov. Rhizomes range from 2.5 to 5.5 mm in diameter and are amphiphloic. Arc-shaped leaf traces display a slightly asymmetrical divergence pattern and radiate from all sides of the stele. Primary xylem maturation is exarch. Multicellular trichomes are present throughout but are produced in greater numbers at rhizome dichotomies. Both pith and cortex are of a distinctive heterogeneous construction. A comparison of this distinctive combination of characters to previously described fern rhizomes reveals that vegetative anatomy may be more taxonomically diagnostic for a broader range of ferns than is commonly thought. This realization provides the impetus to explore more closely the distribution of several anatomic characters among leptosporangiate ferns and to reexamine the value of vegetative anatomy for developing a clearer understanding of fern systematics. [ABSTRACT FROM AUTHOR]

Several fertile pinnules with abaxially borne sporangia have been discovered in calcareous marine nodules from the Middle or Late Eocene Appian Way locality on the east coast of Vancouver Island, British Columbia, Canada. Fertile pinnules are attached in groups of two or three. They are deeply lobed, with each lobe rolled toward the abaxial surface and the entire pinnule rolled toward the abaxial surface to form an irregularly globose structure. Sporangia occur abaxially and form two rows over the entire surface of each pinnule lobe. The midrib of each pinnule lobe is thickened, forming a receptacle from which broadly attached sporangia and numerous paraphyses diverge. As is characteristic of many schizaeaceous ferns, sporangia of the fossil are flask shaped with a short stalk and have a uniseriate, transverse annulus at the apex. Spores are tetrahedral and trilete, like those of the type species for the extinct genus Paralygodium. The new specimens are described as Paralygodium vancouverensis sp. nov. and are compared to both living genera of schizaeaceous ferns and the extinct species Paralygodium yezoense and Anemia poolensis. The unique combination of characters displayed by each of the fossil species reveals the presence of several extinct schizaeaceous lineages and supports interpretations that the diversity of Schizaeaceae s.l. was greater during the Cretaceous and Paleogene than it is today. [ABSTRACT FROM AUTHOR]

Anatomically preserved schizaeaceous vegetative and fertile organs have been identified from the Apple Bay locality (Lower Cretaceous) of Vancouver Island, British Columbia. Specimens are permineralized in calcareous nodules that contain numerous plants and marine invertebrates. Fertile pinnules are pinnately lobed, with abaxial sporangia and abaxially reflexed laminae. The pyriform sporangia have an apical annulus and occur in two rows on each pinnule lobe. Laminar tissue has wavy, thick-walled, adaxial epidermal cells. Spores are tetrahedral to globose with three sets of obliquely arranged parallel muri and correspond to the sporae dispersae genus Cicatricosisporites Potonié et Gelletich. This fertile material most closely resembles Anemia subgenus Anemiorrhiza (Schizaeaceae) and is described as a new species, Anemia quatsinoensis Hernandez-Castillo, Stockey et Rothwell. Fertile pinnae are associated with an exarch, amphiphloic, solenostelic Anemia-like rhizome, with a C-shaped frond trace. Anatomies of the solenostele and frond trace, as well as frond divergence, compare most closely with species of Anemia subgenus Anemiorrhiza and may represent the vegetative shoot of Anemia quatsinoensis. This is the oldest and most complete permineralized fertile material of the genus Anemia in North America, and its presence at Apple Bay is consistent with the hypothesis that much of the diversification of Schizaeaceae had already occurred by the beginning of the Cretaceous. [ABSTRACT FROM AUTHOR]

Anatomically preserved specimens of globose staminate and pistillate inflorescences belonging to Platanaceae have been found in concretions at the Eocene Appian Way fossil locality on Vancouver Island, British Columbia, Canada. The structure of inflorescences and individual flowers, vascular architecture, and pollen morphology were examined. Flowers occur on globose unisexual heads and are supplied at their bases by branching pentagonal vascular traces. Flowers of staminate inflorescences have a well-developed perianth with at least two whorls of tepals. Five stamens with elongate anthers surround a single whorl of five (rarely four) free, nonfunctional carpels that are ovate in longitudinal section and roughly triangular in transverse section. In situ tricolpate pollen 16 μm in polar diameter is found in the anthers. This same pollen is found among the persistent styles of larger pistillate fructifications. The pistillate flowers are identical in structure to staminate flowers but have five fully developed carpels, and they lack stamens. Fruits are glabrous achenes up to 8 mm long. Staminate inflorescences compare most closely to those of Platananthus sp., but the regular co-occurrence of both stamens and rudimentary carpels in the same flower has not previously been reported in the fossil record, and, thus, these specimens have been placed in a new genus and species, Gynoplatananthus oysterbayensis. These platanaceous inflorescences add to our knowledge of the Appian Way flora and provide evidence that rudimentary carpels are an ancient feature within staminate flowers of Platanaceae. [ABSTRACT FROM AUTHOR]

A new genus and species of anatomically preserved fossil filicalean ferns Dickwhitea allenbyensis gen. et sp. nov. is described from the Middle Eocene Princeton Chert of southern British Columbia, Canada. Rhizomes have a parenchymatous pith surrounded by a ring of five amphiphloic cauline bundles and pairs of frond traces that diverge from adjacent cauline bundles in a 2/5 phyllotaxis. The cortex is also parenchymatous except at the periphery, where there is a well-developed sclerotic hypodermis. The stipe is characterized by a pair of hippocampiform bundles, and ground tissues are similar to those of the rhizome. Prominent nests of large cells with black contents occur adjacent to the vascular bundles in the ground tissue of the rhizome and stipe. Roots are diarch with cortex that grades from parenchymatous at the interior to sclerotic at the periphery. The vascular architecture of this fern appears to be novel among known Filicales. There are no gaps in the stele that result from the divergence of either frond or root traces, and there is no evidence that cauline bundles anastomose. Rather, the cauline bundles extend through the rhizome independently of each other, with each cauline bundle producing successive frond traces on alternating tangents. Root traces diverge from the outer surface of cauline bundles as is characteristic of solenostelic filicalean species and dictyostelic tree ferns. Examination of the literature reveals that there is a wide range of variation in filicalean vascular architectures that traditionally has not been recognized. Although there is anecdotal evidence that this newly recognized stelar variation is correlated with patterns of systematic diversity, the overall phylogenetic significance of fern vascular architecture has yet to be fully explored. [ABSTRACT FROM AUTHOR]

Two permineralized conifer pollen cones have been identified from the Appian Way locality on the east coast of Vancouver Island, British Columbia. These cones, found in marine calcareous nodules with invertebrates, are Eocene in age and have been studied with the cellulose acetate peel technique. Cones are small, terminal, and globose, with helically arranged subtending leaves, ensheathing leaves, microsporophylls, and pollen sacs with enclosed pollen grains. Peltate microsporophylls have a distal lamina with three abaxial pollen sacs. Pollen grains are small, subspherical, nonsaccate, and papillate, with a distal leptoma and proximal orbicules. Phyllotaxy of subtending leaves and microsporophylls, number of pollen sacs per microsporophyll, and ultrastructure of pollen grains are similar to those of the taxodiaceous Cupressaceae. These cones have closest similarities to Athrotaxis, Cunninghamia, Sequoia, Sequoiadendron, Taiwania, the extinct Sewardiodendron laxum (sensu Yao et al.), and Athrotaxites berryi. However, they have a combination of characters that make these cones unique among taxodiaceous conifers. Therefore, a new genus and species are described as Homalcoia littoralis Hernandez-Castillo, Stockey et Beard. These cones show a novel combination of characters within the Cupressaceae that extends our understanding of the family and shows the presence of another extinct taxodiaceous genus in the North American Eocene. [ABSTRACT FROM AUTHOR]

Several new broad-leaved monocots were identified in gray siltstones and fine-grained sandstones from the Upper Cretaceous (Campanian-Maastrichtian) St. Mary River Formation near Cardston, Alberta, Canada. Specimens are compression/impressions of long-petiolate aquatic plants that were probably buried in situ. Leaf blades are entire, ovate to elliptic, with deeply cordate bases; leaf blades are 5-12 cm long and 3.5-8.5 cm wide. Petioles are at least 4 mm wide with five to seven primary veins that enter the leaf blade. Venation is campylodromous, resulting in 23-27 primary veins with three medial veins that remain unbranched to the apex. Major and minor secondary veins (ABAB pattern) diverge at angles of 45°-65° near the midveins and 900 near the leaf margin. Tertiary veins are usually unbranched, but occasional dichotomies and anastomoses occur. No freely ending veinlets are visible. The Cardston specimens are compared with extant leaves of Alismatales and show closest similarities to those of Lirnnocharis L., Hydrocleys Rich., and Butomopsis Kunth. These leaves are also similar to fossil leaves of Haemanthophyllum Budantsev, in particular H. cordatum Golovneva from the Maastrichtian-Danian deposits of the Koryak Highlands, Russia. A reexamination of the genus Haemanthophyllum, the generitype (H. kamtschaticum Budantsev), the holotype for H. cordatum, and the Cardston specimens results in the description of a new genus, Cardstonia tolmanii gen. et sp. nov. (Limnocharitaceae). This study points to the need for reexamination of the remaining species in the genus Haemanthophyllum, which appear to represent a diverse assemblage of leaves of varying morphology that are probably not a natural group. [ABSTRACT FROM AUTHOR]

Large numbers of roots and stems of aquatic Lythraceae have been found in association with fruits and seeds of Decodon allenbyensis Cevallos-Ferriz et Stockey in the Princeton chert, British Columbia, Canada. The permineralized fossils come from layer 43 in the chert, part of the Middle Eocene, Allenby Formation. Vegetative remains were studied using the cellulose acetate peel technique in an attempt to reconstruct the whole plant of D. allenbyensis. Reconstruction is based on close anatomical comparisons of tissues in the fossil organs to those of extant Decodon verticillatus (L.) Ell. and on attachment of organs and tissue systems. A detailed description of both root and stem wood anatomy is provided for the fossil species. Stem anatomy is revised for extant D. verticillatus, and detailed root anatomy is described for the first time using paraffin sectioning techniques and scanning electron microscopy. Fossil roots and stems show diffuse porous wood with vessels that are solitary or in radial multiples of two to five with numerous tyloses. Heterocellular rays vary from one to at least five cells wide. Secondary phloem with clusters of thick-walled fibers is preserved in some axes. Most roots and some stems show distinctive concentric layers of thin-walled lacunate phellem, characteristic of submerged aquatics. This tissue has been described in extant Decodon J.F. Gmelin and other Lythraceae. Anatomy of D. allenbyensis indicates that these plants were growing under submerged conditions with stable water levels at the edge of a quiet body of fresh water. [ABSTRACT FROM AUTHOR]

A large number of vegetative and fertile branching systems of Thucydia mahoningensis provide data for interpreting the growth architecture and life-history pattern of a primitive Paleozoic conifer. Internal anatomy is similar to modern conifers, indicating an arborescent life-history pattern. Three categories of vegetative plagiotropic branching systems are recognized, and these resemble developmental variations among lateral branching systems in juvenile trees of the extant conifer Araucaria heterophylla (Salisb.) Franco. Thucydia mahoningensis is considered to be a small tree on the basis of the size and branching pattern of the stem and lateral branching systems and on the basis of internal anatomy. Growth architecture of T. mahoningensis conforms to Massart's model, but fertile remains reveal interesting differences from living species. The T. mahoningensis tree has an orthotropic stem that bears two orders of plagiotropic vegetative shoots. Fertile shoots have a compound ovulate fertile zone and lack vegetative lateral branches. Ovulate branches bear penultimate-type vegetative leaves in the basal region, a compound ovulate fertile zone in the midregion, and ultimate-type vegetative leaves in the distal region. Axillary ovuliferous dwarf shoots of the compound fertile zones correspond to ultimate branches of the vegetative systems. Compound pollen cones are terminal on branches. These and supplementary data from previously described walchian species reveal that the architecture of the most primitive conifers resembles juvenile araucarian conifers and suggest that giant conifers evolved from diminutive trees by the combination of an extended vegetative growth phase and hypermorphoses in leaf development. [ABSTRACT FROM AUTHOR]

Studies aroid seeds from the Middle Eocene Princeton chert. Raphides in idioblasts; Endosperm tissue with dark contents and monocotyledonary embryo; Replacement of tissue with fungal hypha.

Focuses on the anatomical preservation of Williamsonia. Evidence for Bennettitalean reproduction in the late cretaceous of Western North America; Compression and permineralized specimens of vegetative and fertile organs.