Olearia chathamica Kirk is now a synonym of Macrolearia chathamica (Kirk) Saldivia (Saldivia et al. 2022).

Reference

Saldivia, P.; Wagstaff, S.J.; Breitwieser, I.; Orlovich, D.A.; Lord, J.M. 2022: A Generic Taxonomic Synopsis of the Pleurophyllum Clade (Asteraceae: Astereae: Celmisiinae) with the Recognition of the New Zealand Endemic New Genus Macrolearia. Systematic Botany 47: 607–634