New delimitations and phylogenetic relationships of Sabiceeae (Ixoroideae, Rubiaceae) and revision of the Neotropical species of Sabicea Aubl.
type: CreativeWork
description: The pantropical tribe Sabiceeae (Ixoroideae s.l., Rubiaceae) has been variously circumscribed previously with strong conflicts. The monophyly of Sabiceeae including its all established genera or the monophyly of any non-monotypic genus traditionally included in this tribe has never been examined using molecular data sets. Sabicea, the type and most species rich genus of the tribe has not been revised to any extent after its first monographic treatment (Wernham, 1914), mostly based on typological concept. The present study reveals for the first time that neither the tribe Virectarieae, currently established as the associated tribe of Sabiceeae, nor the subtribe Virectariinae is monophyletic; rather, the tribe Sabiceeae including the genera of Virectarieae or Virectariinae is strongly resolved as a monophyletic group in trnT-F and combined ITS-trnT-F trees. This study suggests the broad circumscription of the tribe Sabiceeae (Sabiceeae s.l.) consisting of eight genera: Ecpoma, Hekistocarpa, Pseudosabicea, Sabicea, Schizostigma, Stipularia, Tamridaea, and Virectaria. Additionally, this study suggests the placement of both Pentaloncha and Temnopteryx, in subfamily Rubioideae. The monophyly of the newly delimited Sabiceeae s.l. is entirely based on molecular data. This study reveals that the genera Ecpoma, Pseudosabicea, Sabicea, Schizostigma, and Stipularia, traditionally associated with the tribe Sabiceeae, together form a monophyletic group and their morphological distinctions are not clear-cut. Therefore, all of these genera are merged under Sabicea s.l., and finally the tribe Sabiceeae s.l. is recognized with four genera: Hekistocarpa, Sabicea s.l., Tamridaea, and Virectaria. The resolved clades of combined ITS-trnT-F tree (Chapter 6.1, Fig. 3) indicate that the São Tomean, Malagasy, and all Neotropical Sabicea presumably originated from African ancestors. They reached São Tomé & Principe, Madagascar, and the Neotropics independently via four dispersal events. This …
abstract: The pantropical tribe Sabiceeae (Ixoroideae s.l., Rubiaceae) has been variously circumscribed previously with strong conflicts. The monophyly of Sabiceeae including its all established genera or the monophyly of any non-monotypic genus traditionally included in this tribe has never been examined using molecular data sets. Sabicea, the type and most species rich genus of the tribe has not been revised to any extent after its first monographic treatment (Wernham, 1914), mostly based on typological concept. The present study reveals for the first time that neither the tribe Virectarieae, currently established as the associated tribe of Sabiceeae, nor the subtribe Virectariinae is monophyletic; rather, the tribe Sabiceeae including the genera of Virectarieae or Virectariinae is strongly resolved as a monophyletic group in trnT-F and combined ITS-trnT-F trees. This study suggests the broad circumscription of the tribe Sabiceeae (Sabiceeae s.l.) consisting of eight genera: Ecpoma, Hekistocarpa, Pseudosabicea, Sabicea, Schizostigma, Stipularia, Tamridaea, and Virectaria. Additionally, this study suggests the placement of both Pentaloncha and Temnopteryx, in subfamily Rubioideae. The monophyly of the newly delimited Sabiceeae s.l. is entirely based on molecular data. This study reveals that the genera Ecpoma, Pseudosabicea, Sabicea, Schizostigma, and Stipularia, traditionally associated with the tribe Sabiceeae, together form a monophyletic group and their morphological distinctions are not clear-cut. Therefore, all of these genera are merged under Sabicea s.l., and finally the tribe Sabiceeae s.l. is recognized with four genera: Hekistocarpa, Sabicea s.l., Tamridaea, and Virectaria. The resolved clades of combined ITS-trnT-F tree (Chapter 6.1, Fig. 3) indicate that the São Tomean, Malagasy, and all Neotropical Sabicea presumably originated from African ancestors. They reached São Tomé & Principe, Madagascar, and the Neotropics independently via four dispersal events. This …
author: Khan, Saleh Ahamad
date published: 2007-11-20
date modified: 2026-07-27T18:49:23Z
provider: Universität Bayreuth
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Universität Bayreuth