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Conifers of the taxodiaceous grade of Cupressaceae were more diverse and widespread during the Mesozoic than they are today. The earliest diverging subfamily, Cunninghamioideae, only includes a single extant genus, but has at least 10 fossil genera. Here, two additional cunninghamioid genera are characterized on the basis of permineralized seed cones from the Upper Cretaceous of Hokkaido, Japan. These conifers display seed cone characters typical of cunninghamioids; however, they have a mosaic of characters that are not seen in any reported conifer of Cupressaceae. They are, therefore, designated as two new extinct species: Ohanastrobus hokkaidoensis gen. et sp. nov. and Nishidastrobus japonicum gen. et sp. nov. These newly reported conifers expand the taxonomic and morphological diversity of cunninghamioids. The stratigraphic and paleobiogeographic records of cunninghamioids and other fossil Cupressaceae with foliate seed cones indicate they peak in diversity during the Cretaceous. The living genera Taiwania and Cunninghamia appear during the Albian and Campanian, respectively, and maintain a nearly continuous fossil record through to today, while nearly all other extinct genera of Cupressaceae with foliate cones disappear by the close of the Campanian. As more ancient cunninghamioids are recovered, our understanding of macroevolutionary patterns of this once diverse lineage will be further elucidated. Key words: conifers, cunninghamioids, Cupressaceae, Cretaceous, fossils, seed cones. Les coniferes de la famille des Cupressaceae taxodiacees etaient plus diversifies et repandus au cours du Mesozoique qu'ils ne le sont aujourd'hui. La sous-famille divergente la plus ancienne, les Cunninghamioideae, ne comprend qu'un seul genre existant, mais compte au moins 10 genres fossiles. Ici, deux autres genres de cunninghamioides sont caracterises a partir de cones a graines permineralises provenant du Cretace superieur a Hokkaido, au Japon. Ces coniferes presentent des caracteres de cone a graines typiques des cunninghamioides ; toutefois, ils ont une mosaique de caracteres qui ne sont vus chez aucun conifere signale chez les Cupressaceae. Ils sont ainsi designes comme deux nouvelles especes eteintes : Ohanastrobus hokkaidoensis gen. et sp. nov. et Nishidastrobus japonicum gen. et sp. nov. Ces coniferes nouvellement signales elargissent la diversite taxonomique et morphologique des cunninghamioides. Les enregistrements stratigraphiques et paleobiogeographiques des cunninghamioides et d'autres Cupressaceae fossiles avec des cones a graines folies indiquent qu'ils ont atteint un pic de diversite pendant le Cretace. Les genres vivants Taiwania et Cunninghamia apparaissent respectivement a l'Albien et au Campanien, et conservent un registre fossile presque continu jusqu'a aujourd'hui, tandis que presque tous les autres genres eteints de Cupressaceae a cones folies disparaissent a la fin du Campanien. Au fur et a mesure que des cunninghamioides plus anciens sont retrouves, notre comprehension des modeles macro-evolutifs de cette lignee autrefois diversifiee sera davantage elucidee. [Traduit par la Redaction] Mots-cles : coniferes, cunninghamioides, Cupressaceae, Cretace, fossiles, cones., Introduction The taxodiaceous grade of the Cypress family (Cupressaceae) is comprised of five charismatic lineages (designated as subfamilies) that have extensive fossil records originating in the Mesozoic. The taxodiaceous subfamilies--the [...]

Abstract: Relationships of living and fossil Pinaceae were inferred using parsimony and Bayesian inference of morphological characters and plastid and nuclear DNA sequences. When considering extant taxa only, adding molecular [...]

More than 800 permineralized fagaceous fruits have been studied from the Eocene Appian Way locality of Vancouver Island, British Columbia. These cupulate nuts are the most common fruits preserved at the locality. They occur in calcareous concretions and were studied using the cellulose acetate peel technique. Cupules are borne on a spiny stalk and are broadly ovate in both longitudinal and transverse section. Cupules are evalvate and have both branching and simple spines. A single, ovoid, sclerotic nut is enclosed entirely by the cupule, except at the apex, where a stylar protrusion is free from any surrounding tissues. The nut is bilocular with a glabrous endocarp lining. At maturity, a single seed occupies the locular cavity. The embryo is straight and no endosperm is evident. The single-fruited, spiny cupule is most similar to fruits of Fagaceae subfamily Castaneoideae. Bicarpellate fruits and a glabrous endocarp place them within the fossil genus Cascadiacarpa; however, they differ from Cascadiacarpa spinosa in nut wall anatomy, cupule ornamentation, shape, and size. Fruits of Cascadiacarpa exilis sp. nov. are compared with spiny, small compression and impression fossil fruits from the Eocene Taneum Creek locality of Washington State. The characters of the Washington State fossils overlap with those observed in the anatomically preserved Appian Way cupulate fruits and, as such, may represent compression and impression fossils of the same genus. The permineralized fruits document that evalvate, spiny, cupulate nuts of Fagaceae were present and common in the Eocene of western North America. Key words: Appian Way, Castaneoideae, Eocene, Fagales, fossil, fruits. Plus de 800 fruits de fagacees permineralisees ont ete etudies dans la localite eocene d'Appian Way sur l'Ile de Vancouver, Colombie-Britannique. Ces noix cupuliformes constituent les fruits les plus communs preserves a cet endroit. Ils sont presents dans des concretions calcaires, et ils ont ete etudies par la technique de pelliculation sur acetate de cellulose. Les cupules sont portees sur une tige spinifere et sont largement ovees, tant en section longitudinale que transversale. Les cupules sont evalvees et possedent des epines ramifiees ou simples. Une noix simple, ovoide, sclerotique est entierement encloisonnee par la cupule, sauf a l'apex, ou une protuberance stylaire est libre de tout tissu environnant. Cette noix est biloculaire, avec une couche interne d'endocarpe glabre. A maturite, une seule graine occupe la cavite loculaire. L'embryon est droit et aucun endosperme n'est visible. La cupule spinifere a fruit simple est essentiellement similaire aux fruits de la sous-famille des Castaneoideae appartenant aux fagacees. Les fruits bicarpelles et l'endocarpe glabre les placent au sein du genre fossile des Cascadiacarpa; cependant ils different de Cascadiacarpa spinosa en ce qui a trait a l'anatomie de la paroi de la noix, et a l'ornementation, la forme et de la taille de la cupule. Les fruits de Cascadiacarpa exilis sp. nov. se comparent aux petits fruits spiniferes fossiles par compression et impression de la localite eocene de Taneum Creek, dans l'etat de Washington. Les caracteristiques des fossiles de l'etat de Washington chevauchent celles observees chez les fruits cupuliformes preserves d'Appian Way et, de ce fait, representent des fossiles par compression et impression du meme genre. Les fruits permineralises temoignent que les noix evalvees, spiniformes et cupuliformes des Fagaceae etaient presentes et communes dans l'Eocene de l'ouest de l'Amerique du Nord. [Traduit par la Redaction] Mots-cles: Appian Way, Castaneoideae, Eocene, Fagales, fossiles, fruits., Introduction The fossil record of Fagaceae is one of the most extensive and diverse among angiosperm families (Crepet 1989; Kvacek and Walther 1989; Sims et al. 1998). While most extant [...]

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Relationships of living and fossil Pinaceae were inferred using parsimony and Bayesian inference of morphological characters and plastid and nuclear DNA sequences. When considering extant taxa only, adding molecular to morphological characters resulted in markedly increased resolution and branch support compared with analysis of morphology alone. Including 45 fossil taxa resulted in drastically decreased resolution in morphology-based consensus trees. We evaluated the effect on branch support and resolution of including DNA sequences, deleting fossils lacking information for cone scale apices and seeds, using reduced consensus methods, and using implied weighting, and found that the greatest improvements were found by including DNA sequences and using implied weighting. The tree topologies from parsimony and Bayesian inference confirm previous findings that the fossil genus Pseudoaraucaria and a few species of Pityostrobus from the Lower Cretaceous are related to abietoid genera, and that other species of Pityostrobus are pinoid and closely related to Pinus. Focusing phylogenetic analyses on the most complete fossil cones, specifically those that are anatomically preserved and include both cone scale apices and seeds, and taking into account homoplasy, resulted in the clearest hypotheses for the timing and sequence of diversification in the family. [ABSTRACT FROM AUTHOR]