WAraucaria mirabilis is an extinct species of coniferous tree from Patagonia, Argentina. It belongs to the section Bunya of the genus Araucaria.
WAraucarites sanctaecrucis is an extinct coniferous tree from Patagonia, Argentina. Its exact affinities are unknown and it is currently assigned to the form genus Araucarites of the family Araucariaceae. A. sanctaecrucis are known from petrified fossils of branches, foliage, and cones from the Cerro Cuadrado Petrified Forest.
WCaytonia is an extinct genus of seed ferns.
WCaytonia nathorstii is an extinct species of seed ferns.
WThe Caytoniales are an extinct order of seed plants known from fossils collected throughout the Mesozoic Era, specifically in the late Triassic to Maastrichtian period, around 250 to 70 million years ago. They are regarded as seed ferns because they are seed-bearing plants with fern-like leaves. Although at one time considered angiosperms because of their berry-like cupules, that hypothesis was later disproven. Nevertheless, some authorities consider them likely ancestors of angiosperms, whereas others consider angiosperms more likely derived from Glossopteridales. The origin of angiosperms remains an intriguing puzzle.
WCladophlebis is an extinct form genus of fern, used to refer to Paleozoic and Mesozoic fern leaves that have "fern fronds with pinnules that are attached to the rachis, and have a median vein that runs to the apex of the pinnule, and veins from that are curved and dichotomise". By convention this genus is not used to refer to fossil ferns from the Cenozoic. Ferns with this morphology belong to several families, including Osmundaceae, Dicksoniaceae and Schizaeaceae. Ferns with this morphology are common during the Paleozoic and Mesozoic in both the northern and southern hemispheres.
WCycadeoidaceae is a family of bennettitalean plants which flourished in the Mesozoic era. Two genera, Cycadeoidea and Monanthesia, are currently recognised though most species are poorly known.
WCycadeoidea is an extinct genus of bennettitalean plants known from fossil finds in North America and Europe. They lived during the Jurassic and Cretaceous periods.
WDicksonia is a genus of tree ferns in the order Cyatheales. It is regarded as related to Cyathea, but is considered to retain more primitive traits, dating back at least to the Jurassic and Cretaceous periods. The fossil record includes stems, pinnules, and spores.
WGinkgo huttonii is an extinct Ginkgo species in the family Ginkgoaceae from the Jurassic of England. The fossil is also known by the name, Ginkgoites huttonii, the genus, Ginkgoites, referring to a group of extinct members of the Ginkgoaceae. G. huttonii was a broad-leaved, deciduous gymnosperm bearing resemblance to the only living member of the Ginkgoaceae, Ginkgo biloba.
WThe Ginkgoaceae is a family of gymnosperms which appeared during the Mesozoic Era, of which the only extant representative is Ginkgo biloba, which is for this reason sometimes regarded as a living fossil. Formerly, however, there were several other genera, and forests of ginkgo existed. Because leaves can take such diverse forms within a single species, these are a poor measure of diversity, although differing structures of wood point to the existence of diverse ginkgo forests in ancient times.
WGinkgoales is a gymnosperm order containing only one extant species: Ginkgo biloba, the ginkgo tree. It is monotypic, within the class Ginkgoopsida, which itself is monotypic within the division Ginkgophyta. The order includes five families, of which only Ginkgoaceae remains extant.
WGinkgoites is a genus that refers to extinct plants belonging to Ginkgoaceae. Fossils of these plants have been found around the globe during the Triassic, Jurassic and Cretaceous. The name was created as a form genus in 1919 by Albert Seward who stated: "I ... propose to employ the name Ginkgoites for leaves that it is believed belong either to plants generically identical with Ginkgo or to very closely allied types".
WThe term Pteridospermatophyta refers to several distinct polyphyletic groups of extinct seed-bearing plants (spermatophytes). The earliest fossil evidence for plants of this type is the genus Elkinsia of the late Devonian age. They flourished particularly during the Carboniferous and Permian periods. Pteridosperms declined during the Mesozoic Era and had mostly disappeared by the end of the Cretaceous Period, though some pteridosperm-like plants seem to have survived into Eocene times, based on fossil finds in Tasmania.
WSagenopteris is a genus of extinct seed ferns from the Triassic to late Early Cretaceous.
WSagenopteris phillipsii are leaves of extinct species of seed ferns.
WSagenopteris trapialensis are leaves of extinct species of seed ferns from Chubut, Patagonia Argentina. At the moment, S. trapialensis is based on impression fossils found in the Early Jurassic Lonco Trapial Formation near Paso del Sapo, Chubut Province.
WThe term Pteridospermatophyta refers to several distinct polyphyletic groups of extinct seed-bearing plants (spermatophytes). The earliest fossil evidence for plants of this type is the genus Elkinsia of the late Devonian age. They flourished particularly during the Carboniferous and Permian periods. Pteridosperms declined during the Mesozoic Era and had mostly disappeared by the end of the Cretaceous Period, though some pteridosperm-like plants seem to have survived into Eocene times, based on fossil finds in Tasmania.
WSequoia is a genus of redwood coniferous trees in the subfamily Sequoioideae of the family Cupressaceae. The only extant species of the genus is Sequoia sempervirens in the Northern California coastal forests ecoregion of Northern California and Southwestern Oregon in the United States. The two other genera, Sequoiadendron and Metasequoia, in the subfamily Sequoioideae are closely related to Sequoia. It includes the tallest trees, as well as the heaviest by weight, in the world.
WSphenopteris is a genus of seed ferns containing the foliage of various extinct plants, ranging from the Devonian to Late Cretaceous.
WWilliamsonia is an extinct genus of plant belonging to Bennettitales, an order of seed plants which bore a resemblance to cycads. Fossilized specimens of Williamsonia have been discovered worldwide.
WWilliamsoniaceae is a family within the Bennettitales, an extinct group of seed plants within the Cycadophyta subdivision. Members of this family are believed to have been around two meters tall and with widely serrate leaves along a central stem. Reproductive organs of the Williamsoniaceae have varied widely in the fossil record but almost all have been found to be borne on stalks emerging from a ring of leaves.
WZamites is a genus of fossil tree known from the Mesozoic of North America, Europe and India through the Eocene of North America. It is a form taxon for leaves that resemble the extant cycad Zamia. The fronds are linear or lanceolate in shape, and pinnately compound, with pinnae with parallel veins and smooth margins, and symmetrical and constricted at the base where they are attached obliquely to the upper surface of the rachis. It has been interpreted as a cycad in the family Cycadaceae or a Bennettitalean plant.