J Syst Evol

• Research Articles •    

RADseq resolves the phylogeny of Hawaiian Myrsine (Primulaceae) and provides evidence for hybridization

Marc S. Appelhans1,2*, Claudia Paetzold1, Kenneth R. Wood3, and Warren L. Wagner2   

  1. 1 Department of Systematics, Biodiversity and Evolution of Plants, Albrecht‐von‐Haller Institute for Plant Sciences, University of Goettingen, Untere Karspüle 2, Goettingen 37073, Germany
    2 Department of Botany, Smithsonian Institution, PO Box 37012, Washington, DC 20013‐7012, USA
    3 National Tropical Botanical Garden, 3530 Papalina Road, Kalāheo, HI 96741, USA
  • Received:2020-02-11 Accepted:2020-07-29 Online:2020-08-05

Abstract:

The Hawaiian radiation of Myrsine (primrose family, Primulaceae) is the only one among the ten most species‐rich Hawaiian plant lineages that has never been included in a phylogenetic analysis. Our study is based on a RADseq dataset of nearly all Hawaiian Myrsine species and a Sanger sequencing dataset based on a worldwide sampling of Myrsine and related genera. Myrsine as a whole might be paraphyletic with respect to the monotypic Macaronesian genera Heberdenia and Pleiomeris, whereas Hawaiian Myrsine is resolved as monophyletic. The Sanger sequencing proved to be insufficient to resolve the Hawaiian lineage, whereas RADseq fully resolved the relationships with high support. Hawaiian Myrsine consists of three main lineages, of which one contains the majority of species and is mainly confined to Kauaʻi, and the other two lineages primarily consist of few widespread species. Although phylogenetic reconstructions delivered fully resolved and supported tree topologies, Quartet Sampling and HyDe analyses reveal phylogenetic incongruence throughout the phylogeny and provide the first molecular evidence of extensive hybridization in the lineage.

Key words: HyDe, Island biogeography, Kōlea, Myrsinaceae, Pacific Ocean, Quartet Sampling