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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 [...]

Abstract: 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 [...]

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]

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Copyright of Botany is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]