J Syst Evol

• Research Article •    

Biogeographic history of Pterocarya (Juglandaceae) inferred from phylogenomic and fossil data

Hua Yan1,2†, Peng Zhou1†, Wei Wang3, Jian-Fei Ye4, Shao-Lin Tan1, Chun-Ce Guo2, Wen-Gen Zhang2, Zi-Wei Zhu5, Yi-Zhen Liu1, Xiao-Guo Xiang1,*   

  1. 1. Key Laboratory of Poyang Lake Environment and Resource Utilization Ministry of Education, School of Life Sciences, Nanchang University, Nanchang 330031, China;
    2. Forestry College, Jiangxi Agricultural University, Nanchang 330045, China;
    3. State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China;
    4. School of Ecology, Sun Yat-Sen University, Guangzhou 510275, China;
    5. Jiangxi Academy of Forest, Nanchang 330013, China
    These authors contributed equally to this work.
    *Correspondence:Xiao-Guo Xiang, xiangxg2010@163.com, xiangxg2018@ncu.edu.cn
  • Received:2023-02-21 Accepted:2023-12-26

Abstract: Pterocarya (Juglandaceae) is disjunctly distributed in East Asia and the Caucasus region today, but its fossils are widely distributed in Northern Hemisphere. We first inferred phylogeny with time estimation of Pterocarya under node-dating (ND) based on plastomes of all eight extant species and tip-dating (TD) based on plastomes and 69 morphological characters of 19 extant and extinct species, respectively. We compared the biogeographical reconstructions on the timetrees from ND and TD respectively, and then compiled 83 fossil records and 599 current occurrences for predicting the potential distributions for the past and the future. The most recent comment ancestor of Pterocarya is inferred in East Asia at 40.46 Ma (95% HPD: 28.04–54.86) under TD and 26.81 Ma (95% HPD: 23.03–33.12) under ND. The current distribution was attributed to one dispersal and one vicariant events without fossils, but as many as to six dispersal, six vicariant, and 11 local extinction events when considering fossils. Pterocarya migrated between East Asia and North America via Bering Land Bridge during the early Oligocene and the early Miocene. With the closure of Turgai Strait, Pterocarya dispersed between East Asia and Europe through the Miocene. The potential distribution analyses indicated that Pterocarya preferred warm temperate regions across the Northern Hemisphere since the Oligocene, but the drastic temperature decline caused its extinction in high latitudes. Except P. fraxinifolia and P. stenoptera, suitable habitats for this genus are predicted to contract by 2070 due to climate change.

Key words: biogeography, East Asian-Europe disjunction, fossil, molecular clock, phylogenomics, species distribution modeling