We reconstructed phylogenetic relationships in Leguminosae subfam. Mimosoideae tribe Ingeae using 135 sequences from the nuclear (ITS) and 119 from the plastid (trnL–F) genome, representing 23 of the 36 currently recognized genera in the tribe with newly generated sequences of Blanchetiodendron, Guinetia, Macrosamanea, Thailentadopsis and Viguieranthus and an extensive sampling of Calliandra. Only two of the five Neotropical generic alliances of Barneby & Grimes (1996) were supported as monophyletic. Calliandra is resolved as monophyletic with the inclusion of Guinetia. The five previously proposed sections within Calliandra were not supported by our study. Nevertheless, based on these results, a new infrageneric classification is proposed for Calliandra, and the African species of the genus are assigned to a new genus, Afrocalliandra. Three new sections are proposed for Calliandra: (1) sect. Tsugoideae based on C. ser. Tsugoideae, with four species from northwestern South America; (2) sect. Septentrionales, with six species distributed in dry areas from the United States to Mexico and (3) sect. Monticola, which consists of species restricted to the Espinhaço range of Brazil; these latter species form a clade with low levels of sequence variation, a potential indicator of the recent diversification of this group.

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The genus Aristolochia presents conserved features in its basic structural plan of trap flowers and in its pollination syndrome. Visitors, usually flies, are attracted to the rotting-meat scented flowers and remain trapped until the second day, when the protogynous flowers release them. Aristolochia gigantea Mart. and Zucc showed many of these floral traits but display a citronella-like odour, giving the opportunity to study the reproductive ecology in this atypical species. Characteristics and behavior of pollinators, coupled with the distances between individual plants and populations, are important factors in patterns of genetic diversity. Thus, our objectives were to study the flower visitors, reproductive success, and gene flow in A. gigantea in the Chapada Diamantina, Bahia, Brazil. Results suggest that pollination by flies remains as a conserved interaction within the genus Aristolochia. The main pollinators appeared to be Megaselia spp. (Phoridae), evidenced primarily by the frequency of their occurrence within flowers and the transference of compatible pollen. On the other hand, the moderate to low levels of intrapopulation genetic variability found in A. gigantea, combined with low effective pollination and its reproductive dependence on biotic vectors, indicate that this species may be suffering gene erosion in the remaining populations located at Chapada Diamantina.Résumé : Le genre Aristolochia comporte des particularités conservées dans son plan structural de base de fleurs pièges et dans son syndrome de pollinisation. Les visiteurs, habituellement des mouches, sont attirés vers les fleurs à odeur de viande pourrie et demeurent piégées pendant deux jours, avant que les fleurs protogynes les relâchent. L'Aristolochia gigantea Mart. et Zucc montre plusieurs de ces traits floraux, mais dispense une odeur rappelant la citronnelle, ce qui ouvre la possibilité d'étudier l'écologie reproductive de cette espèce atypique. Les caractéristiques et le comportement des pollinisateurs, couplées avec les distances entre les plantes individuelles et les populations, constituent d'importants facteurs pour le patron de diversité génétique. Ainsi, les objectifs du groupe ont consisté à étudier les visiteurs des fleurs, le succès reproductif et le flux de gènes chez l'A. gigantea, dans la région de Chapada Diamantina, Bahia, au Brésil. Les résultats suggèrent que la pollinisation par les mouches fait l'objet d'une interaction conservée dans le genre Aristolochia. Les principaux pollinisateurs semblent appartenir au genre Megaselia (Phoridae), ce que supporte principalement la fréquence de leur présence dans les fleurs ainsi que le transfert de pollen compatible. En plus, le degré faible à modéré de variabilité génétique intrapopulation retrouvé chez l'A. gigantea, combiné avec le faible degré réel de pollinisation ainsi que sa dépendance reproductive sur des vecteurs biotiques, indique que cette espèce pourrait souffrir d'une érosion génétique chez les populations résiduelles du Chapada Diamantina.

Cattleya elongata is a rupicolous orchid species spread throughout and endemic to outcrop islands in campo rupestre vegetation of the Chapada Diamantina, northeastern Brazil. We scored nine natural populations of C. elongata for morphological and genetic variability, covering the whole distribution area of the species, using allozymes and ISSR markers and morphometric multivariate analyses. Genetic variability in allozimes was relatively high (H e = 0.12-0.25), and unexpectedly higher than the values based on ISSR (H e = 0.16-0.19). The populations present moderate structuring (allozymes, U PT = 0.14; ISSR, U PT = 0.18) and low inbreeding (allozymes, F IS = 0.06). Genetic similarity among the populations was high in both markers, in spite of the discontinuity of the outcrops of the Chapada Diamantina. We found no particular biogeographical pattern to the distribution of the genetic and morphologic similarity among the populations of C. elongata. We found high morphological variability with moderate differentiation among the populations. We did not find any correlation among genetic, morphological, and geographical distances, and among the variability found in the morphological and genetic markers. The differences observed between the two genetic markers and the various morphological markers examined here indicated that the isolated use of any single parameter of these different populations for conservation planning or management would not consider all of the variability to be found in the species, as found in other Brazilian campos rupestres plants.