Resolving relationships in the radiation of Australia's largest pea clade (Fabaceae tribe Mirbelieae) with target-capture sequencing

<h4>Background and aims</h4>Tribe Mirbelieae (Fabaceae) represents one of the great species radiations in Australian flora and the largest in the pea-flowered legumes. Traditional amplicon sequencing has failed to resolve relationships within this species-rich and morphologically diverse tribe.<h4>Methods</h4>Target-capture sequencing was used to reconstruct relationships within the core Mirbelioid legumes, which represent a previously hypothesized rapid radiation that dates to the Oligocene and early Miocene epochs.<h4>Key results</h4>We recovered strongly supported deep nodes resolving relationships between all recognized genera and four novel clades based on 289 low-copy nuclear markers derived from the Angiosperms353 universal probe set. The taxonomically challenging genus Pultenaea was demonstrated to be polyphyletic. Minor changes are required in Aotus, Callistachys, Mirbelia, Oxylobium, Phyllota and Urodon.<h4>Conclusions</h4>Phylogenomic data have robustly resolved relationships in a large legume clade where relationships were long feared irresolvable. This resolution enables the recognition of monophyletic genera within the tribe, with only minimal taxonomic rearrangements. Critically, a new circumscription of Pultenaea supported by both phylogenomic and morphological data has now been achieved.