Costus maasiorum: a new species of Neotropical Costaceae from western Ecuador

We here describe Costus maasiorum, a new species from western Ecuador. This new species shares morphological similarities with Costus macrostrobilus, but differs in having plicate leaves, erect and triangular bract appendages, and semi-tubular elongate flowers. A phylogeny based on 5.9+ million single nucleotide polymorphisms (SNPs) strongly supports a sister relationship between C. maasiorum and C. macrostrobilus. Additional taxonomic sampling in subsequent analyses indicates a close relationship with C. gibbosus and C. antioquiensis. A comprehensive taxonomic description, including detailed photographs and information about the habitat and ecology of the new species are provided. A preliminary conservation status is recommended as Least Concern (LC).