Some distinctive new species of Psychotria (Rubiaceae, Psychotrieae) from Madagascar

Abstract

Psychotria L. (Rubiaceae, Psychotrieae) is an unusually species-rich genus in Madagascar. Recent botanical explorations here have found a number of undescribed species, and some unusual morphological structures for this genus. Here ten new Psychotria species from Madagascar are formally described: Psychotria ambatovensis C.

A revised classification of the sister tribes Palicoureeae and Psychotrieae (Rubiaceae) indicates genus-specific alkaloid accumulation

“…However, numerous exceptions such as different fruit or flower colours occur in part of the range of the genus (e.g. Lachenaud 2019;Taylor 1996Taylor , 2020Taylor et al 2020).…”

“…Furthermore, none of the species of the very rich Malagasy flora with 150? endemic species was studied (Taylor 2020;Taylor et al 2020).…”

More New Species of Psychotria from Madagascar (Rubiaceae, Psychotrieae)

“…The descriptions here follow those of Taylor et al (2020), which mostly followed the format of Bremekamp (1963) to facilitate comparison with that work. Some of Bremekamp's structures are reordered here, however, to follow modern format (e.g., the base of the leaf blade is described here before the apex), but other structures are presented here in the order that follows his sequence (in particular, stipules follow the other parts of the leaf, as in most Rubiaceae treatments of the last 60 years; e.g., Taylor, 2012).…”

“…Psychotria is one of the most species-rich genera in Madagascar (Gautier et al, 2012; Taylor & Razafimandimbison, in press). The genus was recently reviewed taxonomically and morphologically there by Taylor (2020), who noted that recent botanical exploration has found additional species that are new to science (Taylor et al, 2020). Several of these have morphological features that are uncommon or apparently unique in Psychotria , as discussed and detailed by Taylor (2020).…”

“…The genus was recently reviewed taxonomically and morphologically there by Taylor (2020), who noted that recent botanical exploration has found additional species that are new to science (Taylor et al, 2020). Several of these have morphological features that are uncommon or apparently unique in Psychotria , as discussed and detailed by Taylor (2020). Ten distinctive new Psychotria species from Madagascar are described here, to expand our knowledge of this exceptional, threatened flora and to document the morphological variation that has arisen through the radiation of Psychotria on this single island.…”