Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


Biological Sciences

First Advisor

Shirley C. Tucker


The floral development of representatives from some of the informal taxonomic groups of the Caesalpinieae was examined. The floral developmental data was then used in a phylogenetic analysis in combination with more traditional morphological characters, including floral, vegetative and fruit characters. The analysis of 53 taxa and 84 characters produced 1215 equally parsimonious trees of length 386 (CI =.317, RI =.585, RCI =.186). Based on this analysis Caesalpinia sensu lato is not monophyletic, since at least two of the other genera in the Caesalpinia group are nested within Caesalpinia sensu lato. Of the infrageneric groups within Caesalpinia sensu lato, the infrageneric groups Libidibia and Brasilettia, and Caesalpinia subgenus Mezoneuron are monophyletic, but the infrageneric groups Caesalpinia sensu stricto, Poincianella, and Russellodendron are not monophyletic. Although many new characters were used in the phylogenetic analysis of the Caesalpinieae, no characters were found which specifically unite the members of the Caesalpinieae. Based on this analysis, the Caesalpinieae is comprised of several disparate lineages and is not a natural group. Two of the informal taxonomic groups of the Caesalpinieae, the Caesalpinia and Peltophorum groups, are not monophyletic based on this analysis. One member of the Peltophorum group, Campsiandra comosa, is more closely related to the Gleditsia and Poeppigia groups than to the rest of the Peltophorum group. The other members of the Peltophorum group included in this analysis are nested within the Caesalpinia group. The Caesalpinia/Peltophorum clade (excluding Campsiandra comosa) is derived within the Leguminosae and is the sister group to the Cassiinae (Cassia, Senna, and Chamaecrista). Together these two clades are sister to a Detarieae/Papilionoideae clade. The Gleditsia group, Poeppigia group and Campsiandra comosa from the Peltophorum group are in a clade with Ceratonia siliqua (Cassieae). Information on floral development was successfully used, along with more traditional morphological characters, in a phylogenetic analysis of the Legominosae.