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 ofStranvaesiaand 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 theStranvaesiaclade, a conclusion further bolstered by cytonuclear and gene tree discordance. The well-inferred phylogenetic backbone revealed an updated generic delimitation ofStranvaesiaand 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.

Due to the complicated evolutionary history in Pourthiaea, ninety-seven taxa have been described since 1784, and ninety-one of them are validly published taxa, five are naked names, and one is an invalid name. After a comprehensive and critical evaluation, 213 names have been published, including new combinations, new status, and new names; this may be due to the controversial taxonomic position of Pourthiaea in the apple tribe, Maleae. We herewith provide a taxonomic checklist of Pourthiaea for further taxonomic and evolutionary studies. We also lectotypify two taxa: Photinia amphidoxa var. stylosa and P. glabra var. fokienensis.

Lycoris longifolia, a new species from China, was described and illustrated here. Our phylogenomic evidence based on whole plastomes strongly supported the separate phylogenetic position of this new species, and morphologically it could also be distinguished by its long leaves with a distinct purplish-red midrib on the abaxial surface.