J Syst Evol ›› 2021, Vol. 59 ›› Issue (1): 73-82.DOI: 10.1111/jse.12567

• Research Articles • Previous Articles     Next Articles

Phylogeny and biogeography of the hollies (Ilex L., Aquifoliaceae)

Xin Yao1,2* , Yu Song1,2 , Jun‐Bo Yang3, Yun‐Hong Tan1,2,4*, and Richard T. Corlett1,2*   

  1. 1Center for Integrative Conservation, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China
    2Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, Yunnan 666303, China
    3Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
    4Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences, Nay Pyi Taw 05282, Myanmar
  • Received:2019-10-18 Accepted:2020-01-07 Online:2020-01-15 Published:2021-01-01

Abstract: The holly genus, Ilex L., in the monogeneric Aquifoliaceae, is the largest woody dioecious genus (>664 spp.), with a near‐cosmopolitan distribution in mesic environments. We constructed a phylogeny based on two nuclear genes, representing 177 species spread across the geographical range, and dated using macrofossil records. The five main clades had a common ancestor in the early Eocene, much earlier than previously suggested. Ilex originated in subtropical Asia and extant clades colonized South America by 30 Ma, North America by 23 Ma, Australia by 8 Ma, Europe by 6 Ma, and Africa by 4 Ma. South and North America were colonized multiple times. Ilex also reached Hawaii (10 Ma) and other oceanic islands. Macrofossil and pollen records show the genus has tracked mesic climates through time and space, and had a wider distribution before late Miocene global cooling. Our phylogeny provides a framework for studies in comparative ecology and evolution.

Key words: Aquifoliales, biogeography, cosmopolitan distribution, dioecy, long distance dispersal