Data_and_scripts_Notelaea

Tackling the complicated infrafamilial
classification of the economically important Oleaceae requires a piecemeal
approach that addresses generic circumscriptions. Here, focusing on the
distinct clade formed by the generic complex Nestegis, Notelaea, Osmanthus, Phillyrea, and Picconia
within the subtribe Oleinae, we aim to elucidate their boundaries and
relationships and to evaluate their biogeographic history in light of their peculiar
disjunct distribution in Macaronesia, the Mediterranean Region, and the
Pacific. Based on phylogenomic data from plastid and nuclear DNA and extensive sampling,
the results show six subclades within this generic complex, which are also
geographic segregates found in Australia (Notelaea),
Hawaiian Islands (Nestegis sandwicensis),
Macaronesia (Picconia), Mediterranean
Region (Phillyrea), New Caledonia (Osmanthus section Notosmanthus), and New Zealand (Nestegis
s.s.). Accounting for broad morphological overlaps within this clade, we
recognize three genera (Phillyrea, Picconia, and Notelaea s.l.), subsuming all Pacific taxa under Notelaea s.l. Molecular dating and
biogeographic analyses indicate that this clade originated in Eurasia during
the Early Miocene (ca. 23 Mya) and that dispersal only can be favored to
explain its global disjunct distribution. Although the colonization route to
the Hawaiian Islands is unclear, island-hopping and local extinction seem to be
the hallmark of the evolutionary history of this group.