A molecular phylogeny of the pantropical papilionoid legume Aeschynomene supports reinstating the ecologically and morphologically coherent genus Ctenodon

• DOI: 10.13102/neod.131.1
• Publication Date: 2020-08-30T19:10:18Z
• Authors: D Cardoso; C Mattos; F Filardi; A Delgado-Salinas; M Lavin; P Moraes; F Tapia-Pastrana; H Lima
• Keywords: Pantropical; Monophyly; Paraphyly; Molecular Phylogenetics

The pantropical and morphologically diverse genus <i>Aeschynomene</i> (Leguminosae, Papilionoideae) comprises ca. 180 species, but its monophyly has never been comprehensively addressed in a molecular phylogenetic context of the dalbergioid clade. Here we have assembled most complete DNA sequence data (nuclear ribosomal ITS/5.8S plastid genes <i>trnL</i> intron protein-coding <i>matK</i>), representatively sampled both closely related <i>Dalbergia</i> <i>Machaerium</i>, as well all currently accepted genera from dalbergioids. Bayesian maximum likelihood analyses unequivocally confirm non-monophyly <i>Aeschynomene</i>. pantropically distributed sect. <i>Aeschynomene</i>, often inhabiting riparian wetland habitats, is paraphyletic with respect to mostly African <i>Bryaspis</i>, <i>Cyclocarpa</i>, <i>Geissaspis</i>, <i>Humularia</i>, <i>Kotschya</i>, <i>Smithia</i>, South American monotypic <i>Soemmeringia</i>. strongly supported coherent clade comprising species traditionally classified within <i>Ochopodium</i>, greater ecological predilection for neotropical fire-prone savannas seasonally dry tropical forests woodlands, here elevated generic rank. As such, this lineage re-established previously <i>Ctenodon</i>. A description <i>Ctenodon</i> 78 new combinations associated infraspecific taxa are provided, 24 lectotypifications.