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Premise: An anatomically preserved fossil fern sporeling has been discovered in a Lower Cretaceous marine concretion from Vancouver Island, British Columbia, Canada, providing an opportunity to characterize rhizome growth from an extinct species. Methods: The specimen was studied from serial transverse sections prepared by the cellulose acetate peel technique. Results: The rhizome ranges from ~0.7 to 1.1 mm in diameter, has a sclerenchymatous pith, a stele that attains a dictyoxylic architecture, and sclerenchymatous outer cortex, features that are characteristic of osmundaceous rhizomes. Cauline xylem forms a medullated protostele or solenostele at some levels, but is dissected into discrete xylem bundles at others. Fronds diverge in a helical phyllotaxis, range up to 1.1 mm in greatest dimension, and have a C‐shaped trace and outer cortex of sclerotic cells. Inside the sclerenchyma of the petioles are two lateral sclerotic strands and a sclerotic bundle adaxial to the trace. Together, these characters reveal the occurrence of a new species, Todea minutacaulis and provide evidence for developmental changes that occur in the rhizome as the sporeling increased in size. Conclusions: Small size of the specimen, medullated protostelic‐dictyoxylic solenostelar vascular architecture, and incompletely sclerified cells apically reveal that osmundaceous sporeling development has remained constant since at least the Early Cretaceous. Together with Todea tidwellii and Osmunda vancouverensis that also are present in the Apple Bay flora, this sporeling documents the occurrence of a multispecies assemblage of osmundaceous ferns and demonstrates that the genus Todea was diversifying rapidly by the Early Cretaceous. [ABSTRACT FROM AUTHOR]

Premise: Exceptional anatomical preservation of a fossil araucarian seed cone from a marine carbonate concretion from Vancouver Island, British Columbia, Canada provides unusually complete evidence for cone structure including seeds, megagametophytes, microgametophytes, and embryos of an Upper Cretaceous (Campanian) species of Araucaria, providing important new insights into the structure and relationships of Cretaceous Northern Hemisphere Araucariaceae. Methods: The cone was studied from serial thin sections prepared by the coal ball peel technique. Phylogenetic analysis using a modified morphological matrix with both discrete and continuous characters was performed using TNT version 1.5. Results: The nearly spherical cone, 6 × 6 cm in diameter, has helically arranged cone‐scale complexes, consisting of a large bract with an upturned tip and a small, fleshy ovuliferous scale. Vascularization of the cone‐scale complex is single at its origin. Widely winged bracts, with a bulging base, contain numerous vascular bundles, interspersed with transfusion tissue, and a large number of resin canals. Seeds are ovoid, 1.2 cm long, 1.2 cm in diameter. Nucellus is free from the integument, except at its base, with a convoluted apex, containing possible pollen tubes. Megagametophytes and mature cellular embryos occur in several seeds. Conclusions: This small cone with attached, imbricate leaves, wide bracts, and unusually large seeds, most closely resembles those of Araucaria Section Eutacta. Width and continuity of secondary xylem in the cone axis, and intact cone‐scale complexes indicate that this cone probably did not disarticulate readily at maturity. When added to a modified, previously published phylogenetic analysis, Araucaria famii sp. nov. enhances our understanding of the Cretaceous radiation of Northern Hemisphere Araucaria Section Eutacta. [ABSTRACT FROM AUTHOR]

Premise of the study: Two ovulate conifer cones, one of which is attached terminally to a short leafy shoot, reveal the presence of a new species of Hughmillerites in the Early Cretaceous Apple Bay flora of Vancouver Island, British Columbia, Canada. This ancient conifer expands the diversity of Cupressaceae in the Mesozoic and reveals details about the evolution of Subfamily: Cunninghamioideae. • Methods: Specimens were studied from anatomical sections prepared using the cellulose acetate peel technique. • Key results: Vegetative shoots have helically arranged leaves that are CunninghamiaAike. Seed cones have many helically arranged bract/scale complexes in which the bract is larger than the ovuliferous scale. Each ovuliferous scale has three free tips that separate from the bract immediately distal to an inverted seed. Several ovuliferous scales show interseminal ridges between seeds. • Conclusions: This study documents a new extinct species of cunninghamioid conifers, Hughmillerites vancouverensis, expanding the record of the genus from the Late Jurassic to the Early Cretaceous. This new extinct species emphasizes the important role that conifers from subfamily Cunninghamioideae played in the initial evolutionary radiation of Cupressaceae. In light of recent findings in conifer regulatory genetics, we use H. vancouverensis to hypothesize that variations of expression in certain gene homologues played an important role in the evolution of the cupressaceous ovuliferous scale. [ABSTRACT FROM AUTHOR]