Fertile from the Jurassic of Patagonia: mosaic evolution in the Dipteridaceae-Matoniaceae lineage.

has been postulated as a monophyletic group, whose precise position within the Gleichenoid families Dipteriaceae and Matoniaceae, remains poorly understood. Previously described specimens are based on frond fragments and its fertile morphology is represented by a few, poorly preserved specimens. We describe a new species based on the largest collection of fertile specimens known to date and discuss the evolutionary history of the genus based on the additional reproductive characters provided by the fossils described.

Assessing the evolutionary history of the fern family Dipteridaceae (Gleicheniales) by incorporating both extant and extinct members in a combined phylogenetic study.

Premise Of The Study: Dipteridaceae is a lineage of ferns that has existed from the early Mesozoic and is known for its extensive fossil record. By integrating information from all described extant and extinct genera into a single phylogenetic study, this paper aims to examine the taxonomy of the group on a whole and explore character evolution within the lineage across time.

Methods: A morphological matrix of 51 characters was developed for 72 species (43 extinct and 29 extant) based on published information.

Ontogenetic and temporal trajectories of chemical defence in a cyanogenic eucalypt.

Many studies have shown that similarly aged plants within a species or population can vary markedly in the concentration of defence compounds they deploy to protect themselves from herbivores. Some studies have also shown that the concentration of these compounds can change with development, but no empirical research has mapped such an ontogenetic trajectory in detail. To do this, we grew cyanogenic Eucalyptus yarraensis seedlings from three half-sibling families under constant glasshouse conditions, and followed their foliar cyanogenic glycoside (prunasin) concentration over time for 338 days after sowing (DAS).