New fossil Pinaceae from the Early Cretaceous of Mongolia

Abstract

Exceptionally well-preserved pinaceous leaves and seed cones are abundant in unconsolidated Early Cretaceous lignites in central Mongolia. These fossils include two seed cones, both of which have helically arranged bract–scale complexes with two winged seeds on the adaxial surface. The larger of the two seed cones, described as Picea farjonii sp. nov., is cylindrical to ellipsoidal, and was borne terminally on a stout shoot. The bract is small and tridentate. Leaf bases on the shoots are helically arranged, and attached leaves are linear and flattened. In all of the morphological and anatomical features that are preserved, P. farjonii is very similar to extant Picea. The smaller seed cone, described as Pityostrobus stockeyae sp. nov., shows features of several genera of extant Pinaceae. This cone is ellipsoidal and was borne terminally on a long, slender shoot. The bract is thin and triangular proximally, but the distal portion is thicker, needle-like, and deciduous. Picea farjonii and Pityostrobus stockeyae were abundant in conifer-dominated swamps in Mongolia during the Aptian–Albian and provide further support for the importance of plants related to extant Pinaceae in the vegetation of the Northern Hemisphere at this time.