Morphometric Analysis as a Tool to Resolve a Taxonomic Complex in Myrcia sect. Calyptranthes (Myrtaceae, Myrteae)

Abstract

Abstract— Specimens attributed to Myrcia chytraculia and associated species form a complex within M. sect. Calyptranthes, occurring sympatrically throughout the Caribbean and Central America and sharing a continuously variable suite of morphometric traits. To ascertain whether species within this complex should be treated as separate or conspecific taxa, seven morphometric traits and a further two discrete characters are analysed using univariate and multivariate statistics. Leaf size and shape are found to be indicative of subspecies, and significant mean differences of traits can be found between groups, though they overlap throughout the range of the M. chytraculia complex. As a result of these findings, updated taxonomy for this group is proposed, creating the new combinations Myrcia chytraculia var. americana, Myrcia chytraculia var. pauciflora, and M. chytraculia var. zuzygium, as well as seven new synonyms. A distribution map and a key to the new varieties are also included.