Format: ORAL

Rocio Deanna1,2

1 Instituto Multidisciplinario de Biología Vegetal, IMBIV (CONICET-UNC), Córdoba, Argentina 2 Department of Ecology and Evolutionary Biology, University of Colorado at Boulder, Boulder, U.S.A. rociodeanna@gmail.com

The placement of extinct taxa on phylogenies relies on scoring informative morphological characters, which can be difficult given the fragmentary nature of the fossil record. Although detailed studies of Solanaceae fossils remain few, the family exhibits wide variation in seed and fruit traits to use in estimating fossil placement from morphological data. Therefore, we reviewed a total of 106 seed and seven fruit fossils of Solanaceae, including two recently published South American species that are the oldest records in the family. We scored 28 traits, including 11 continuous and 17 discrete, for all the fossils gathered and almost 400 extant taxa, sampling at least one species per genus. We then performed a cluster analysis to morphologically compare these fossil seeds to extant Solanaceae, along with a phylogenetic analysis including all the morphological traits and 10 DNA regions in order to infer the phylogenetic placement of the fossils. We also reconstructed the ancestral states of the most conspicuous morphological traits over a molecular phylogenetic tree to finally compare the morphological evolution inferred with the placement of the fossils. The clusters found in the statistical analysis were congruent with the phylogenetic placement of the fossils in all the species, except by some fossil seeds. According to the morphological reconstructions, traits that have been acquired only once in the family were the most informative to place the fossils, like the finger-like appendages in the fruiting calyx of the fruit fossil Lycianthoides calycina placed in the chili pepper clade. Converged traits (e.g., inflated fruiting calyx) were less informative but the combination of fruiting calyx traits was sufficient to place the Physalis fruit fossils. Continuous traits were highly informative, especially in the placement of the fossil seeds. These results lay the foundation for new total evidence dating analysis for the entire family.