Using Molecular, Morphological, and Palynological Evidence to Transfer Strumpfia maritima to the Monotypic Tribe Strumpfieae (Cinchonoideae, Rubiaceae), and a Re-delimitation of the Tribe Chiococceae

Abstract—

Strumpfia maritima is a morphologically unique member of the Rubiaceae that has held several taxonomic placements for a long time. In the most recent tribal delimitations within the subfamily Cinchonoideae, Strumpfia was included in the tribe Chiococceae, based solely on molecular phylogenetic positioning, despite the presence of significant morphological and palynological differences between Strumpfia and the other genera of the tribe. Previous studies refrained from including Strumpfia in the Chiococceae because of its numerous morphological and palynological differences, and the inclusion of Strumpfia creates a tribe without a single synapomorphy. Our study of genetic divergences among the tribes of the subfamily Cinchonoideae using trnL-F data, analyzed using both maximum parsimony and Bayesian inference, provides additional evidence for including Strumpfia in the monotypic tribe Strumpfieae.