- Evolutionary ecology research
- Horticultural research
- Plant diversity research
- Amalie Dietrich project
- Australian freshwater algae
- Australian mesic zone biota
- Biology of Myrtaceae
- Cycad evolution and diversity
- DNA of ground orchids
- DNA studies of Restionaceae
- Evolution of Australian Utricularia
- Evolution of Proteaceae
- Fern biodiversity of Australia
- Key to the Lichen Genus Pertusaria
- Lamiaceae & Urticaceae
- Lepidoziaceae - southern liverworts
- Marine algae
- New Species and phylogeny in Restionaceae
- Phylogenetic biome conservatism
- Phylogeny and new species of Australian Utricularia
- Phylogeny of Orchidaceae tribe Diurideae
- Pollination studies in Prostanthera
- Project Camellia
- She-oaks - tough survivors
- Telopea special edition
- Theaceae of South-East Asia
- Trees of Papua New Guinea
- Tristaniopsis in south-east Asia
- Urticaceae of Java
- XVIII International Botanical Congress
- Plant pathology research
- Herbarium & resources
- Scientific publications
Evolution of Australian Utricularia
Dr Richard W. Jobson - Systematic Botanist
Utricularia L. (Lentibulariaceae) is the largest genus of carnivorous angiosperms containing 217 recognised species worldwide. Utricularia exhibits an extraordinary range of morphological diversity, occupying nutrient deficient habitats including epiphytic, rheophytic, suspended aquatic, and terrestrial, and have evolved metabolically expensive suction bladder-traps that are subject to strong selection that depends on assemblages of prey.
In his 1989 monograph of Utricularia Peter Taylor delimited the genus into the following two subgenera: Polypompholyx (three species), including two sections (Tridentaria and Polypompholyx); and Utricularia (211 species), including 35 sectional groupings. Currently, the genus is divided into three subgenera, including Polypompholyx, Bivalvaria and Utricularia. One of these subgenera, Polypompholyx, now includes section Pleiochasia.
In previous phylogenetic studies, I have sampled heavily in subgenera Bivalvaria and Utricularia, and until recently the 37 endemic Australasian species of subgenus Polypompholyx have remained unstudied. After extensive fieldwork, and with use of herbarium sheet resources, sufficient material for DNA extraction has been collected. Phylogenetic analyses of sequence data from chloroplast and nuclear markers, and morphological characters, are being used to assess evolutionary and biogeographic patterns and taxonomic limits within subgenus Polypompholyx.
The project has established the sister relationship of sections Polypompholyx and Pleiochasia, and future work will determine how many species comprise the variable ‘U. dichotoma complex’ (U. dichotoma, U. monanthos, U. beaugleholei, U. novae-zelandiae), and examine unusual filiform corolla lobes that have evolved within the lineage three times independently (U. dunlopii, U. dunstaniae-U. antennifera, U. capilliflora). The distribution of three of these species is sympatric near the base of the Arnhem Land Escarpment, which raises the possibility that pollinator driven selection pressure acted on lobe elongation. Future studies of this novel model of floral mimicry will involve population level ecology, phylogeography, and investigations of floral development genes that may be involved.
My research will provide necessary data for production of a revision of the Australian species for inclusion in the Flora of Australia, and assessment of conservation status for endangered species and their environmentally sensitive habitats.
Photos: R. Jobson, N. Rebbert, A. Orme, M. Hingst