The use of pollen morphology and wood anatomy in the study of the phylogeny of Ebenaceae and Rutaceae subtribe Cuspariinae

The following thesis is an anatomical study specializing in pollen morphology and wood anatomy. Chapter one examines the pollen morphology and wood anatomy of the Ebenaceae, chapter two the pollen morphology of the subtribe Cuspariinae of the Rutaceae, and chapter three provides a model for quantitative analysis of pollen morphology for use in phylogenetic studies.; The first chapter discusses the pollen morphology and wood anatomy of the family Ebenaceae and its usefulness to taxonomic classification. Pollen grains from 170 specimens representing four genera and 92 of the 450-500 species, of Ebenaceae were examined by light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The pollen of the Ebenaceae is relatively uniform; however, subtle variation is present, particularly in sculpturing patterns and size classes. Wood from 148 specimens representing 91 species were examined by LM and SEM. The wood anatomy of Ebenaceae as a whole is distinctive; however, much of the variation in anatomical features occurs among the species of the large genus Diospyros. This diversity in the wood characters is similar to that of most other characters used to classify Diospyros. Until additional anatomical and morphological characters are fully understood and are subjected to a phylogenetic analysis, generic delimitation within the family will remain problematic.; The second chapter investigates the pollen morphology of the subtribe Cuspariinae and its usefulness to taxonomic classification. Pollen grains from 111 collections representing 71 species of the 125 species and 24 of the 26 genera were examined by LM, SEMI and TEM. The pollen morphology of this subtribe is very diverse particularly in sculpturing patterns and aperture types. Pollen data correlate well with macromorphological characters and are taxonomically useful.; The third chapter addresses the problem of pollen size class delimitation. Pollen size classes have been defined by Erdtman (1969) and Walker and Doyle (1975) as arbitrary groups which usually do not correspond to statistically significant differences among taxa. A model is proposed, using conventional statistical procedures coupled with data visualization, in an effort to address the problem of character state delimitation in pollen size classes. As a result the four genera of the Ebenaceae can be coded into three character states for size class.