Repeated parallel losses of inflexed stamens in Moraceae: Phylogenomics and generic revision of the tribe Moreae and the reinstatement of the tribe Olmedieae (Moraceae)

Abstract

We present a densely sampled phylogenomic study of the mulberry tribe (Moreae, Moraceae), an economically important clade with a global distribution, revealing multiple losses of inflexed stamens, a character traditionally used to circumscribe Moreae. Inflexed stamens facilitate ballistic pollen release and are associated with wind pollination, and the results presented here suggest that losses of this character state may have evolved repeatedly in Moraceae. Neither Moreae nor several of its major genera (Morus, Streblus, Trophis) were found to be monophyletic. A revised system for a monophyletic Moreae is presented, including the reinstatement of the genera Ampalis, Maillardia, Taxotrophis, and Paratrophis, and the recognition of the new genus Afromorus. Pseudostreblus is reinstated and transferred to the Parartocarpeae, and Sloetiopsis is reinstated and transferred to the Dorstenieae. The tribe Olmedieae is reinstated, replacing the Castilleae, owing to the reinstatement of the type Olmedia and its exclusion from Moreae. Streblus s.str. is excluded from Moreae and transferred to the Olmedieae, which is characterized primarily by involucrate inflorescences without regard to stamen position. Nine new combinations are made.

A dated phylogeny shows Plio‐Pleistocene climates spurred evolution of antibrowsing defences in the New Zealand flora

“…Finally, the relationships among species within genera are also consistent with previous work (except for Muehlenbeckia , see next paragraph), some based on plastid DNA (Maurin, 2020b for Pennantia , Maurin & Smissen, 2021 for Corokia ); others on nuclear ribosomal markers (e.g. Gardner et al ., 2021 for Streblus ; Mitchell et al ., 2009 for Melicytus ; Appelhans et al ., 2014 for Melicope ) or based on morphological characters (e.g. Aagesen, 1999 for Discaria ).…”

Comparative and phylogenetic analyses of the chloroplast genome reveal the taxonomy of the Morus genus

“…It is clear that the genus Morus is monophyletic and is divided into five clades ( Figure 4 ). Recently, M. mesozygia and M. insignis , native to Africa, which used to belong to the Morus genus, were eliminated from the Morus genus on the basis of phylogenetic analyses of supercontig sequences from 246 Moraceae samples ( Gardner et al., 2021 ). Here, we also found that M. mesozygia did not belong to Morus because M. mesozygia was clustered with Ficus and Broussonetia ( Figure 4 ).…”

“…In 14 different groups, each group randomly selected a representative CP genome, together with other 36 CP genomes from the unclassified group, to form 50 CP genomes for phylogenetic analysis. The CP genome sequences of Broussonetia papyrifera ( Broussonetia genus, GenBank: MZ662865), Ficus carica ( Ficus genus, GenBank: KY635880) and Morus mesozygia ( Afromorus genus, GenBank: MZ274134) ( Gardner et al., 2021 ) were selected as outgroups. All complete CP genome sequences were aligned using MAFFT v7.455 ( Katoh and Standley, 2013 ), and the alignments were trimmed with trimAl v1.4.rev15 ( Capella-Gutiérrez et al., 2009 ).…”

“…Mulberry ( Morus L., Moraceae) ( Group, 2009 ) comprises a variable number of species, with the first 7 described by Linnaeus (1753) . The traditional taxonomy of Morus is often based on minor morphological differences ( Gardner et al., 2021 ). Various researchers identified 5, 8, 13, 16, 24, and 35 Morus species using morphological and/or molecular methods ( Bureau, 1873 ; Koidzumi, 1930 ; Hotta, 1954 ; Zhou and Gilbert, 2003 ; Zeng et al., 2015 ; Jain et al., 2022 ).…”

“…In 2015, we proposed eight species in the Morus genus on the basis of ITS (internal transcribed spacer) sequences, which were recently verified by an analysis of population genetics ( Jiao et al., 2020 ). A recent investigation of Moraceae revealed that the genus Morus is a monophyletic group without M. mesozygia and M. insignis , and the delimitation of M. alba may be worth further investigating ( Gardner et al., 2021 ). However, the genome-based taxonomy of the genus Morus remains unexplored ( Jiao et al., 2020 ).…”