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Flora of North America North of Mexico
The Flora of North America north of Mexico treats all native and naturalized vascular plants and bryophytes in Canada, Greenland, St. Pierre et Miquelon, and the continental United States including
Systematic Foliar Morphology of Phyllanthoideae (Euphorbiaceae).
Results indicated that several major tribes recognized in the most recent classification of the Phyllanthoideae subfamily are essentially monophyletic, including Aporuseae, Bridelieae, Drypeteae, and most of WielandieAE, whereas others, notably Antidesmeae, are probably paraphy- letic.
Feral sheep on Socorro Island: facilitators of alien plant colonization and ecosystem decay
Investigation of the role of feral sheep in facilitating the naturalization of alien plants and degrading a formerly robust and stable ecosystem of Socorro Island provides support for the hypothesis that disturbance of a pristine ecosystem is generally required for the colonization and naturalizationof alien plants.
Phylogenetic Implications of Pollen Ultrastructure in the Oldfieldioideae (Euphorbiaceae)
The pollen structure of members of Euphorbiaceae subfamilies Oldfieldioideae and Phyllanthoideae was studied using scanning and transmission electron microscopy in order to assess taxonomic
Pollen Ultrastructure of the Biovulate Euphorbiaceae
The most widespread structural type consisted of a foot layer that is either thin and irregular or absent, an interstitium composed of irregular to columellate exine deposits that are discontinuous from the foot layer, if present, and a tectum composed of laterally appressed baculate elements that delimit fine microperforations.
Relationships Within the Spiny-Fruited Umbellifers (Scandiceae subtribes Daucinae and Torilidinae) as Assessed by Phylogenetic Analysis of Morphological Characters
A phylogenetic study of these spiny-fruited umbellifers based on morphology reaffirms the monophyletic of subtribe Torilidinae and provides greater resolution of relationships within each of the subtribes than do either of the separate analyses.
Systematic foliar morphology of Phyllanthoideae (Euphorbiaceae). II: Phenetic analysis
Cladistic analysis of 43 foliar characters was used to explore the phylogeny of genera in Phyllanthoideae and to test the systematic value of foliar morphology, challenging the widely held belief that leaves are of little systematic value.
Phylogenetic Relationships of Didymocistus and Hymenocardia (Euphorbiaceae)
The genus Hymenocardia lacks the microchanneled tectum, granular interstitium, and thin foot-layer of the Urticales, but has many palynological features found in the Phyllanthoideae and should be retained in the Euphorbiaceae in that subfamily.