Valner Jordao1P, Bente Klitgaard2, Asif Tamboli3, Bo-Yoon Seol3, Domingos Cardoso1, In-Su Choi3

1Rio de Janeiro Botanical Garden, Rio de Janeiro, Brazil; 2Department of Accelerated Taxonomy, Royal Botanic Gardens, Kew, London, United Kingdom; 3Department of Biological Systems Sciences, Hannam University, Daejeon, Korea

The papilionoid legume genus Humularia currently has 34 species distributed across Central and Eastern Sub-Saharan Africa. It was described in 1954 in an attempt to resolve the taxonomic complexity between Bryaspis and Geissaspis and is morphologically distinct from these related genera by the combination of emarginate inflorescence bracts and panduriform standard petals. To expand genomic knowledge of Humularia and provide a foundation for phylogenetic, taxonomic, and evolutionary studies, as well as to support future research on genetic diversity and conservation, the presented study was conducted on comprehensive plastid genome characterization of seven species: H. elisabethvillena (Brunudi), H. reekmansii (Tanzania), H. apiculata, H. kapiriensis, H. minima, H. pseudoaeschynomene, and H. rosea (Zambia). We used genome skimming sequencing methods to assembly the plastomes. The Humularia plastomes range from 155,462 to 156,160 bp in length and with a GC content of 35.6%, comprising 127 genes, including 82 protein-coding genes, 37 tRNAs, and 8 rRNAs. A plastome-based phylogeny including available sequences from GenBank strongly supported a monophyletic Humularia as sister to the African genus Kotschya. However, rigorously confirming the monophyly of Humularia will require a broader taxon sampling within the largely polyphyletic genus Aeschynomene in the Dalbergia clade.