Early Cretaceous abietoid Pinaceae from Mongolia and the history of seed scale shedding

Premise Seed cones of extant Pinaceae exhibit two mechanisms seed release. In “flexers” the cone scales remain attached to central axis, while flexing and separating from each other release seeds. “shedders” are shed with seeds either remaining scale or becoming detached. The early fossil history Jurassic Early Cretaceous is dominated by cones, systematic information provided shedding has been overlooked rarely integrated data based on compression permineralized specimens. We describe earliest best-documented evidence a “shedder” Aptian–Albian Mongolia. Methods Lignite samples Tevshiin Govi locality were disaggregated in water, washed, dried air. Fossils compared material using LM CT scans. Results Lepidocasus mellonae gen. et sp. nov. characterized that disarticulated at maturity obovate bract–scale complexes have distinctive ribbed surface an abaxial covered abundant trichomes. ovuliferous ca. 30–40 resin canals, but only scarce xylem near attachment axis. Resin vesicles present integument. Phylogenetic analysis places as sister Cedrus within abietoid grade. Conclusions exquisite preservation trichomes L. raises questions about their potential ecological function living Pinaceae. also shows dispersal syndrome, feature often overlooked, evolved during Cretaceous.