Format: ORAL

Gitte Petersen1, Benjamin Anderson2, Brendan Lepschi3, Daniel Nickrent4, Jennifer Tate5, Amir Sultan6

1 Stockholm University, Stockholm, Sweden 2 Department of Biodiversity, Conservation and Attractions, Western Australia, Perth, Australia 3 Australian National Herbarium, Centre for Australian National Biodiversity Research, Canberra, Australia 4 Cornell University, Ithaca, USA 5 Massey University, Palmerston North, New Zealand 6 National Herbarium of Pakistan, Islamabad, Pakistan

Parasitic plants in the family Viscaceae (mistletoes) have been shown to have highly unusual mitochondrial genes compared to other flowering plants. Genes encoding respiratory complex I are even lost. In order to investigate where in the evolutionary history of this group these bizarre changes have occurred, a solid hypothesis of their evolutionary relationships is needed. In order to reconstruct a phylogeny, we have sampled all Australian representatives of both Viscaceae and the closely related family Amphorogynaceae (both included in Santalaceae s.l.) as part of the GAP initiative. Since the families are not restricted to Australia, numerous species from other regions of the world were also sampled. Taxon sampling additionally included other representatives of the order Santalales for a total of approximately 200 samples. Using target capture sequencing with the Angiosperms353 bait set, we obtained data from over 300 nuclear loci, which were used for phylogenetic reconstruction based on both concatenation and coalescence methods. The phylogenetic trees derived from the two methods are largely congruent and confirm a sister group relationships of Viscaceae and Amphorogynaceae. Generic relationships within the families are also largely consistent with previous hypotheses, but the denser taxon sampling allows for more detailed hypotheses about species relationships within genera. The phylogeny will be used to trace the evolution of mitochondrial genes, and preliminary data suggest a deeper origin than ancestral Viscaceae for the onset evolutionary drastic changes. It is even possible that gene loss has occurred multiple times during the evolution of mistletoes.