Nicholas Tippery, Doctoral Candidate

Office: BioPharm 317

Voice: (860) 486-3937

Fax: (860) 486-6364

E-mail: nicholas.tippery@uconn.edu

Mailing address:

Research interests:

Introduction
    My graduate research involves the aquatic and wetland plant family Menyanthaceae (Bercht. & Presl), in particular the systematics and taxonomy of species, and the evolution of floral reproductive systems. Species of Menyanthaceae are found worldwide, and are currently divided taxonomically among five genera. The reproductive systems of Menyanthaceae species are of particular interest, because the family contains both hermaphroditic and dioecious species, and many hermaphroditic species are also heterostylous. In addition, species in the genus Nymphoides Ség., while rooted in the substrate, have a floating-leaf habit reminiscent of many other, unrelated aquatic plant lineages.

Taxonomy
    The five genera of Menyanthaceae are Liparophyllum Hook.f., Menyanthes L., Nephrophyllidium Gilg (= Fauria Franch.), Nymphoides Ség, and Villarsia Vent. Menyanthes and Nephrophyllidium are found only in the northern hemisphere, Liparophyllum and Villarsia are restricted to the southern hemisphere, and Nymphoides has a cosmopolitan (worldwide) distribution, with centers of diversity in Africa, Australia, India, and the Americas. Liparophyllum, Menyanthes, and Nephrophyllidium are monotypic (having only one species each), the genus Villarsia contains 17 species, and Nymphoides has about 40-50 species.

Vegetative morphology
    Four genera of Menyanthaceae have an erect inflorescence and grow in wetland habitats. Nymphoides, the most speciose genus, consists mostly of floating-leaved plants, where the leaves serve to keep the flowers above the water surface. I am studying the mechanism through which the floating leaf and inflorescence apparatus arose from a wetland ancestor.

Reproductive morphology
    In addition to their diversity in vegetative morphology, species of Menyanthaceae possess an array of reproductive systems, including hermaphroditism, gynodioecy, and dioecy. Heterostyly also occurs in all genera but Liparophyllum, with the majority of species in Nymphoides and Villarsia being heterostylous. Using a phylogenetic framework, I plan to infer the directionality of conversions to and from particular reproductive systems, and address the evolutionary forces promoting changes in floral morphology.