Morphological diversification in Psychotria of Madagascar Below several unusual morphological characters of Psychotria in Madagascar are highlighted and some terminology is clarified, because much Psychotria morphology has been incorrectly understood due to incomplete and conflicting descriptions. All the features discussed below are taxonomic characters used by BREMEKAMP (1963) and/or TAYLOR (in press). The morphological features of Psychotria ’s species are correlated with their ecology and subject to selective pressure, so morphology is important for understanding evolutionary radiation of this genus in Madagascar. Psychotria shows notable morphological variation throughout its range (ANDERSSON, 2002), while at the same time most of its species are remarkably similar in characters and pollination and dispersal modes. This means identification of individual species requires careful morphological observation. Psychotria has more morphological diversity in Madagascar than in most other geographic regions, and has some features here that are uncommon or unknown elsewhere.

Published as part of Taylor, Charlotte M., 2020, Overview of Psychotria in Madagascar (Rubiaceae, Psychotrieae), and of Bremekamp's foundational study of this group, pp. 51-70 in Candollea 75 (1) on page 62, DOI: 10.15553/c2020v751a5, http://zenodo.org/record/7182908