Carapichea includes at least 23 Notropical species found in wet, seasonal, dry, and gallery forest from Nicaragua to Bolivia and eastern Brazil. The center of species diversity is in the Amazon basin, in particular in its northeastern portion.
Carapichea was originally named for one species from French Guiana, C. guianensis Aubl., which was observed to be very similar to Psychotria. Recent molecular systematic studies of the tribe Psychotrieae have changed our understanding of the relationships within this group, and based on this Andersson (2002) recognized Carapichea and expanded its circumscription. Delprete (2003), Taylor in 2006 in the Flora of Ecuador, and Jardim & Zappi (2008)subsequently included additional species, and Taylor & Gereau (2013) presented a significantly expanded circumscription of Carapichea and a detailed morphological overview. They built on Andersson's work to characterize the genus by its characteristic marcescent stipules, inflorescences that are capitate or branched to 1-2 orders with the flowers sessile to shortly pedicellate, lack of ethanol-soluble pigments in the seed testa, and aperturate pollen of a generalized Psychotrieae form (i.e., not specialized as in Palicourea). Most of the species included now in Carapichea are poorly known and the this hypothesis of it circumscription needs further testing.
The genus Carapichea was characterized essentially by the same morphological features, in particular the head-like inflorescences enclosed by well developed bracts, as Cephaelis and these genera have been confused taxonomically and especially nomenclaturally. The name Carapichea is older than Cephaelis, but was overlooked for a long time so to maintain nomenclatural stability, the name Cephaelis is conserved when these are considered synonyms; however when they are treated as separate genera, both names can be used. Cephaelis is today considered a synonym of Palicourea s. lat., which differs in general from Carapichea in its stipules that are persistent and bilobed and its inaperturate pollen. Another name that has been used for these plants is Uragoga, and this is now a synonym of Carapichea (by lectotypification). Baillon published this name as his own inadvertently, when he intended to use Linnaeus's old name Uragoga. However this name was only used by Linnaeus in works that pre-date the start of our plant nomenclature so when Baillon used it, that constituted a new publication of the name. And, Baillon used Uragoga for plants that already had validly published names, Carapichea and Cephaelis, so the name Uragoga was illegitimate. The history and confusion of these names is detailed by Taylor & Gereau (2013).
In this expanded circumscription, Carapichea includes the cultivated species C. ipecacuanha, and the previously separated monotypic genus Stachyococus of western Amazonia. Taylor & Gereau (2013) separated 7 informal groups but no formal infrageneric taxa. The variation within this genus in pyrene form and dehiscence is extensive, among the species included based on molecular analyses along (Taylor & Gereau, 2013: p. 9, fig. 1).
Author: C.M. Taylor
The content of this web page was last revised on 23 May 2013.
Taylor web page: http://www.mobot.org/MOBOT/Research/curators/taylor.shtml