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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]

An anatomically preserved seed cone from Late Cretaceous (Santonian-Coniacian) sediments of the Yezo Group on the Japanese Island of Hokkaido documents additional diversity among sequoioid conifers, and reveals previously unknown mechanisms for pollination and post-pollination seed enclosure in the conifer family Cupressaceae. The cylindrical seed cone of Stockeystrobus interdigitata gen. et sp. nov., consists of a central axis bearing helically arranged bract-scale complexes. Individual complexes are tightly packed and peltate in form, with completely fused bracts and scales. Peltate heads of adjacent complexes are attached to each other by elongated interdigitating epidermal trichomes. Each complex bears 6-8 inverted seeds on the adaxial surface of the inside of the peltate bract-scale complex head. Seeds occur in a single row, are roughly disk shaped, with broad wings in the major plane of symmetry. The nucellus is attached to the seed integument at the chalaza and free distally, with a convoluted apex. This cone reveals greater diversity of sequoioid reproductive biology than is represented among living species, and demonstrates that completely enclosed cones with well protected seeds were produced by Late Cretaceous fossil conifers of the Cupressaceae. [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 the study: Seed cone morphology and anatomy reflect some of the most important changes in the phylogeny and evolutionary biology of conifers. Reexamination of the enigmatic Jurassic seed cone Pararaucaria patagonica reveals previously unknown systematically informative characters that demonstrate affinities with the Cheirolepidiaceae. This paper documents, for the first time, internal anatomy for seed cones of this important extinct Mesozoic conifer family, which may represent the ghost lineage leading to modern Pinaceae. • Methods: Morphology and anatomy of cones from the Jurassic La Matilde Formation in Patagonia are described from a combination of polished wafers and thin section preparations. New photographic techniques are employed to reveal histological details of thin sections in which organic cell wall remains are not preserved. Specific terminology for conifer seed cones is proposed to help clarify hypotheses of homology for the various structures of the cones. • Key results: Specimens are demonstrated to have trilobed ovuliferous scale tips along with a seed enclosing pocket of ovuliferous scale tissue. Originally thought to represent a seed wing in P. patagonica, this pocket-forming tissue is comparable to the flap of tissue covering seeds of compressed cheirolepidiaceous cones and is probably the most diagnostic character for seed cones of the family. • Conclusions: Pararaucaria patagonica is assigned to Cheirolepidiaceae, documenting anatomical features for seed cones of the family and providing evidence for the antiquity of pinoid conifers leading to the origin of Pinaceae. A list of key morphological and anatomical characters for seed cones of Cheirolepidiaceae is developed to facilitate assignment of a much broader range of fossil remains to the family. This confirms the presence of Cheirolepidiaceae in the Jurassic of the Southern Hemisphere, which was previously suspected from palynological records. [ABSTRACT FROM AUTHOR]

* Premise of the study: Pinaceae and nonpinoid species are sister groups within the conifer clade as inferred from molecular systematic comparisons of living species and therefore should have comparable geological ages. However, the fossil record for the nonpinoid lineage of extant conifer families is Triassic, nearly 100 million years older than the oldest widely accepted Lower Cretaceous record for Pinaceae. An anatomically preserved fossil conifer seed cone described here extends the stratigraphic range of Pinaceae nearly 30 million years, thus reducing the apparent discrepancy between evidence from the fossil record and inferences from systematic studies of living species. * Methods: Material was prepared as serial thin sections by the cellulose acetate peel technique, mounted on microscope slides, and viewed and photographed using transmitted light. * Key results: A large cylindrical cone consisting of bract-scale complexes that diverge from the cone axis in a helical phyllotaxis has bracts and scales that separate from each other in the midregion and are of equal length and of nearly equal width. The cone has two inverted and winged seeds that are attached to the adaxial surface of each cone scale and, thus, represents an early member of the Pinaceae. * Conclusions: Eathiestrobus mackenziei gen. et sp. nov. extends the fossil record for well-documented members of the family Pinaceae from the Lower Cretaceous to the Kimmeridgian Stage of the Upper Jurassic. This species also clarifies the set of characters that are diagnostic for seed cones of Pinaceae and reveals possible plesiomorphic characters for seed cones of the family. [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]

Reports the discovery of a compound pollen cone among a walchian conifers in Pennsylvania. Description on the pollen cone; Axillary structures; Implications of the discovery.

Provides information on the phylogeny of conifers using the specimen Barthelia furcata. Leaf structure and morphology; Stem anatomy; Pollen cones and pollen; Ovulate fructifications; Correlation and distinctiveness of Barthelia organs; Comparisons among ancient coniferophyte pollen cones.

A single cylindrical seed cone 2 cm long, 1.1 cm wide has been found preserved in a calcium carbonate marine concretion from the Hakobuchi Formation (late Campanian-early Maastrichtian) of Hobetsu, Hokkaido, Japan. The cone, attached to a bent peduncle lacking leaves, has helically arranged bract/scale complexes that arise at right angles from the cone axis in the middle of the cone. The cone axis, ca. 1 mm wide, has a broad cylinder of secondary vascular tissue, and lacks a continuous resin canal system. Bract-scale complexes are laminar, cordate-orbiculate, and upturned distally, consisting primarily of bract tissue with no visible scale tip. The vascular trace to the bract/scale complex originates as a rod that divides laterally into several traces at the level of seed attachment. A single resin canal originates at the base of the bract-scale complex abaxial to the vascular strand, but more distally there are up to ca. 15 large resin canals that form a single row. Two to three inverted winged seeds are attached adaxially near the cone periphery. Cone structure and vascularization are most similar to those in the Cupressaceae, Subfamily Taiwanioideae, differing from living Taiwania cryptomerioides by having up to three seeds/scale rather than two, an abruptly upturned bract tip, in details of bract/scale vasculature, and a cone peduncle lacking leaves. This cone is described as Mukawastrobus satoi Stockey, Nishida and Rothwell. Together with previously described Early to Late Cretaceous taiwanioid seed cones from Mongolia and Hokkaido the new species demonstrates that the taxonomically diagnostic characters of such conifers are as subtle as those of Cretaceous and Cenozoic sequoioid Cupressaceae. This realization emphasizes that evolutionary diversification and turnover among taiwanioid conifers during the Cretaceous and Paleogene are probably far greater than currently recognized. [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]

The fossiliferous ironstone deposits of the Upper Cretaceous Horseshoe Canyon Formation in the Drumheller badlands, Alberta, Canada, contain a diverse, anatomically preserved flora. Within this assemblage occur abundant stems, leafy shoots, leaves, ovuliferous cones, and pollen cone clusters that are here described as a new species of Cunninghamia. The stems have persistent leaf bases and plagiotropic branching. Some stems show several growth increments, and the cortex and pith are made up of resin canals, large parenchymatous cells, and lysigenous cavities. Leafy shoot axes have parenchymatous cells, resinous cells, lysigenous cavities, and resin canals within the cortex and pith. The leaves are helically arranged, lanceolate to falcate, with two abaxial stomatal bands, a large central resin canal, and two smaller lateral canals. The ovuliferous cones have numerous helically arranged bract scale complexes. The bracts and three-lobed ovuliferous scale are variously ornamented. Anatomical features of bracts include a well-defined hypodermal layer and resin canals with adaxial traces. A single vascular trace enters the complex and divides to produce the ovuliferous-scale trace and bract traces. Ovules/seeds are ovoid and weakly winged. The pollen cone-bearing branch apices show stalks of at least 17 pollen cones arranged in a pseudowhorl. Each stalk consists of an inflated base surrounded by 5-6 scale-like leaves. The anatomy and morphology of the fossil material agrees so closely with that of modern Cunninghamia that we are confident in describing it as a new species of this genus, Cunninghamia taylorii sp. nov. The present material provides a rare opportunity to contribute toward a better understanding of the specific variation, biology, ecology, and evolutionary history of cunninghamioid Cupressaceae. [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]

The authors comment on an article regarding a study of charred conifer twigs from the Lower Cretaceous Chaswood Formation of Canada. They mention the dominance of Chaswood Formation palynoflora by pteridophyte spores including Aequitriradites verrucosus, Distaltriangulisporites perplexus, and Trilobosporites canadensis. They also note the explosive evolutionary radiation undergone by the Pinaceae during the Early Cretaceous period.

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]

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]