![]() ![]() 1992 Saiki and Kimura 1993 Stockey et al. Many fossils of early Cupressaceae have been described based on permineralized, lignified, and compression seed cones from Jurassic to Late Cretaceous deposits (e.g., Harris 1943, 1953, 1979 Miller 1975 Nishida et al. A morphological cladistic analysis of the phylogenetic position of Pentakonos and Stutzeliastrobus suggests that an expanded cunninghamioid clade followed by Stutzeliastrobus are the successive sister groups to all other extant Cupressaceae.Īmong extant families of conifers, Cupressaceae has an especially rich and diverse fossil record. Morphological features of Stutzeliastrobus suggest a relationship with Taiwania, but the bract-scale complexes bear up to four inverted winged seeds rather than the two commonly seen in living Taiwania.Ĭonclusions. Together with previously described fossils, Pentakonos and Stutzeliastrobus provide additional evidence that both Cunninghamia-like and Taiwania-like plants were important elements in the early diversification of the Cupressaceae s.l. 30–70 helically arranged woody bract-scale complexes that lack a conspicuous, free ovuliferous scale. are terminal and single on leafy shoots with helically arranged falcate scale leaves. Pentakonos adds to the diverse Cunninghamia-like seed cones known from the early fossil record of Cupressaceae. Adaxially, the free tip of the membranous ovuliferous scale is denticulate, and the scale bears five small, thin-winged seeds. 25–30 helically arranged, papery bract-scale complexes that have minute teeth. has seed cones that are up to 7 mm long with ca. Methodology. Early Cretaceous (Aptian-Albian) bulk lignite samples collected from the Tevshiin Govi locality were disaggregated in water, cleaned with hydrochloric and hydrofluoric acids, washed, and dried in air. ![]() Here, we describe two new genera of fossil seed cones similar to those of Cunninghamia and Taiwania. Seed cones of both Cunninghamia and Taiwania bear helically arranged bract-scale complexes, but a free ovuliferous scale is present only in Cunninghamia. ![]() Premise of research. The two living species of Cunninghamia form a clade that is sister to the rest of the Cupressaceae sensu lato, within which the monotypic extant genus Taiwania is sister to all Cupressaceae except Cunninghamia. ![]()
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