Nightmare or delight: taxonomic circumscription meets reticulate evolution in the phylogenomic era
ID: 613 / 375
Proposed Symposium Title: Nightmare or delight: taxonomic circumscription meets reticulate evolution in the phylogenomic era
Ze-Tao Jin1,2,3, Richard G.J. Hodel4, Dai-Kun Ma2,3, Hui Wang2,3,5, Guang-Ning Liu3, Chen Ren6, Bin-Jie Ge7, Qiang Fan8, Shui-Hu Jin5, Chao Xu2,3, Jun Wu1, Bin-Bin Liu2,3
Affiliations: 1 State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China 2 State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, Beijing 100093, China 3 China National Botanical Garden, Beijing, Beijing 100093, China 4 Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013-7012, USA 5 College of Forestry and Biotechnology, Zhejiang Agriculture and Forestry University, Hangzhou, Zhejiang 311300, China 6 Key Laboratory of Plant Resources Conservation and Sustainable Utilization & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong 510650, China 7 Eastern China Conservation Center for Wild Endangered Plant Resources, Shanghai Chenshan Botanical Garden, Shanghai, Shanghai 201602, China 8 State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China
Phylogenetic studies in the phylogenomics era have demonstrated that reticulate evolution greatly impedes the accuracy of phylogenetic inference, and consequently can obscure taxonomic treatments. However, the systematics community lacks a broadly applicable strategy for taxonomic delimitation in groups identified to have pervasive reticulate evolution. The red-fruit genus, Stranvaesia, provides an ideal model for testing the effect of reticulation on generic circumscription when hybridization and allopolyploidy define a group’s evolutionary history. Here, we conducted phylogenomic analyses integrating data from hundreds of single-copy nuclear (SCN) genes and plastomes, and interrogated nuclear paralogs to clarify the inter/intra-generic relationship of Stranvaesia and its allies in the framework of Maleae. Analyses of phylogenomic discord and phylogenetic networks showed that allopolyploidization and introgression promoted the origin and diversification of the Stranvaesia clade, a conclusion further bolstered by cytonuclear and gene tree discordance. The well-inferred phylogenetic backbone revealed an updated generic delimitation of Stranvaesia and a new genus, Weniomeles, characterized by purple-black fruits, trunk and/or branches with thorns, and fruit core with multilocular separated by a layer of sclereids and a cluster of sclereids at the top of the locules. Here, we highlight a broadly-applicable workflow for inferring how analyses of reticulate evolution in phylogenomic data can directly shape taxonomic revisions.