The tropical African Geophila ingens (Rubiaceae‐Psychotrieae) reinvestigated

Abstract

New collections of Geophila ingens are used for a detailed documentation, description, and discussion of the ecology and affinities of this poorly known African species. It is mainly characterised by its variable leaves, the stamen insertion below the internal indumentum of the corolla tube and the straight pyrenes. The ovate leaf blades with frequently rounded bases and the sometimes slightly woody base of the stems indicate that G. ingens may be a primitive representative of the genus. G. ingens occurs and reproduces in closed canopy forests. It has a macrodisjunct distribution (Cameroon, Congo‐Kinshasa and Uganda), corroborating existing hypotheses on the location of glacial forest refuges.

Phylogeny and generic limits in the sister tribes Psychotrieae and Palicoureeae (Rubiaceae): Evolution of schizocarps in Psychotria and origins of bacterial leaf nodules of the Malagasy species

“…Polyphyly of Geophila-Geophila is a pantropical genus of about 24 species ( Piesschaert et al, 1998 ;Taylor et al, 2004 ;Dessein et al, 2011 ;Govaerts et al, 2013 ), which is characterized by creeping, stoloniferous, and herbaceous habit; cordate leaves; and red or black drupaceous fruits. Most species are found in tropical Africa and the neotropics; each region contains nine species.…”

“…More variation than recognized by Bremekamp (1958Bremekamp ( , 1963 in fruit characters has now been documented in Rubiaceae, in particular within the lineages and individual species of Psychotrieae ( Piesschaert, 2001 ) and Palicoureeae ( Piesschaert et al, 1998 ;Piesschaert, 2001 ;Taylor and Gereau, 2013 ). Schizocarps have evolved independently numerous times in different lineages of the angiosperms, e.g., Apiaceae, Araliaceae, Rosaceae, Rubiaceae.…”

Pyrene and pollen observations in the pantropical genus Geophila (Rubiaceae‐Psychotrieae)

“…The genus comprises f 20 species, 10 of which are neotropical (Taylor 1996) and one is pantropical (G. repens). The recent rediscovery of the ill-known African species G. ingens (Piesschaert et al 1999) inspired us to investigate carpological and pollen morphological features in a limited selection of other Geophila species, since these features seem to be most promising in the Psychotrieae.…”

<I>Geophila erythrocarpa</I> (<I>Rubiaceae</I>), a new species from D.R. congo and Zambia

“…stipule morphology, pubescence pattern on the petioles, pubescence pattern on the inside of the corolla tube, fruit colour and pyrene morphology. Pollen also provides useful taxonomic data, but pollen studies in Geophila are often hampered by lack of suitable flowering material (Piesschaert et al 1999a) and are of course of little use for routine determinations.…”