Many key aspects of early angiosperms are poorly known, including their ecophysiology and associated habitats. Evidence for fast-growing, weedy angiosperms comes from the Early Cretaceous Potomac Group, where angiosperm fossils, some of them putative herbs, are found in riparian depositional settings. However, inferences of growth rate from sedimentology and growth habit are somewhat indirect; ...

We describe a new genus and species of Mecoptera with siphonate mouthparts, Sinopolycentropus rasnitsynigen. et sp. n., assigned to the family Pseudopolycentropodidae Handlirsch, 1925. The specimen was collected from late Middle Jurassic nonmarine strata of the Jiulongshan Formation in Inner Mongolia, northeastern China. The new material provides additional evidence for an early diversification...

The great evolutionary success of angiosperms has traditionally been explained, in part, by the partnership of these plants with insect pollinators. The main approach to understanding the origins of this pervasive relationship has been study of the pollinators of living cycads, gnetaleans, and basal angiosperms. Among the most morphologically specialized living pollinators are diverse, long-pro...

Fleshy structures associated with the ovule/seed arose independently several times during gymnosperm evolution. are linked to protection and dispersal, present in all four lineages of extant gymnosperms. The ontogenetic origin fleshy could be different, spans from ovule funiculus Taxus baccata aril, integument Ginkgo biloba, modified bracts as case Ephedra species. This variability ontogeny is ...

BACKGROUND AND AIMS During embryo development in most gymnosperms, the establishment of the shoot apical meristem (SAM) occurs concomitantly with the formation of a crown of cotyledons surrounding the SAM. It has previously been shown that the differentiation of cotyledons in somatic embryos of Picea abies is dependent on polar auxin transport (PAT). In the angiosperm model plant, Arabidopsis t...

The genus Ceratocystis sensu stricto includes species that are insect-vectored, plant pathogens, occurring mainly on angiosperm hosts. Species in the Ce. coerulescens complex form a morphologically distinct group that are pathogens on gymnosperms (Pinaceae) and angiosperms. In recent years, species in the Ce. coerulescens complex have been intensively studied based on their morphology and isozy...

BACKGROUND AND AIMS The closely related NAC family genes NO APICAL MERISTEM (NAM) and CUP-SHAPED COTYLEDON3 (CUC3) regulate the formation of boundaries within and between plant organs. NAM is post-transcriptionally regulated by miR164, whereas CUC3 is not. To gain insight into the evolution of NAM and CUC3 in the angiosperms, we analysed orthologous genes in early-diverging ANA-grade angiosperm...

Abstract In this review, we explore the origin of rudimentary embryo, its relationship to other kinds plant embryos and role in diversification angiosperms. Rudimentary have a length:width ratio ≤2.0, they organs, including cotyledon(s) primary root. A literature survey failed reveal pre-angiosperms, suggesting that kind embryo is an angiosperm invention. Although proembryos some gymnosperms an...