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Fly-speck fungi reproduce via thyriothecia that consist of sporogenous tissue appressed to cuticle surfaces of plant leaves and covered by a shield-like scutellum. Thyriothecial scutella likely evolved repeatedly in Dothideomycetes (Ascomycota), and their morphology varies by lineage. Fly-speck fungi have an exceptionally good fossil record that begins in the Mesozoic. The interpretation of scutellum characters in fossils may provide insights into origins of Dothideomycetes and help calibrate the timing of ascomycete evolution. From sediments of the Lower Cretaceous (125–112 Ma) Potomac Group of Virginia, from Dutch Gap Canal, lower Zone 1, we found scutella similar to those of extant Aulographaceae (Dothideomycetes), attached to a single piece of dispersed coniferous cuticle. We analyze hyphae and scutellum development among four extant Aulographaceae species for comparison with the fossil. The excellent preservation of fungi on the leaf cuticle surface allows us to infer a developmental sequence for the fossil. Scutellum development begins with coordinated growth of multiple neighboring generator hyphae and continues with hyphae producing two-dimensional pseudomonopodial, dichotomous, radial growth. Asci and ascospores were not found. We coded states for seven morphological characters using direct observations of the fossil and eight extant taxa, and using the literature for 28 others. We inferred a phylogeny using nuclear 18S and 28S rDNA of 36 extant taxa, 34 Dothideomycetes and two Arthoniomycetes. The phylogeny includes newly determined sequences from five species, two from Aulographaceae. With a branch-and-bound search, we inferred the most parsimonious placements of the fossil given the molecular tree topology. The parsimony analysis constrained by the rDNA phylogeny places the fossil taxon among stem lineages near Aulographaceae or among the known living members of Aulographaceae. We describe the fossil morphotype as Protographum luttrellii, gen. et sp. nov. The fossil provides the oldest evidence of morphological characters restricted among extant fungi to Aulographaceae. [ABSTRACT FROM AUTHOR]

The evolutionary history of Pinaceae is documented by numerous fossils, which include a number of anatomically preserved ovulate cones with many systematically informative characters. To date, four extinct genera have been recognized:Pseudoaraucaria,Pityostrobus,ObirastrobusandEathiestrobus. A new pinaceous cone from the Early Cretaceous of California is described asPityostrobus pluriresinosasp. nov., adding to the diversity of known Cretaceous pinaceous cones. Phylogenetic analysis places the new fossil cone in the pinoid clade along withPinus,Eathiestrobusand numerous species ofPityostrobus. Combined with a non-metric multidimensional scaling ordination, the data reinforce that whilePityostrobusdoes not represent a natural genus, it likely reflects the rapid evolution of Pinaceae by showing that ovulate cone morphospace was widely occupied byPityostrobusthat has become more restricted in extant genera. Early Cretaceous taxa from Europe and eastern North America show the broadest occupation of morphospace, which then became more restricted to morphologies typical of the pinoid clade in the Late Cretaceous. Taxa from western North America and Asia are more similar to extant genera and occupy a smaller part of the morphospace, highlighting that eastern North America–Europe probably represents an original centre of early diversification for Pinaceae. [ABSTRACT FROM AUTHOR]