Botanic Gardens Trust, Sydney, Australia

Utricularia

Phylogeny and new species of Australian Utricularia

Dr Richard W. Jobson - Systematic Botanist

The genus Utricularia (Lentibulariaceae) contains 214 monographed species worldwide, with approximately 62 (47 endemic) of these found in Australia. Utricularia exhibits an extraordinary range of morphological diversity, occupying nutrient deficient habitats. A phylogenetic study of the Australian species will be supported by a 2012-13 Research Grant from the Australian Biological Resources Study ($33,000 over three years). This project will incorporate future data with previously acquired sequencing matrices that include related genera, and other species from across the world.

The project will examine species level relationships across these understudied clades, and also investigate high levels of intraspecific morphological variability in several widely distributed species complexes. Resolution of boundaries in the major Australian clades will shed light on the evolution of unusual floral and bladder-trap morphologies, while also contributing more broadly to the understanding of historical biogeography and evolution of the Australian flora.

Preliminary phylogenetic work, and observations of morphological characters, has recently led to the differentiation of two novel taxa formerly considered to belong within the species U. dichotoma. One of these new species, U. blackmanii, is distributed in Queensland between Townsville and Mareeba, and is formally described in an upcoming  article in Telopea. The second new species, U. sp. ‘Mt Gambier’, has been determined phylogenetically and requires further fieldwork to assess levels of morphological variation across its range. 

A third new species, U. corneliana, is a suspended aquatic plant that was discovered whilst surveying various swamps in North Queensland. Thus far this species is only know to occur in an ephemeral mountain swamp west of Tully, with its closest relative distributed across tropical Africa.  A taxonomic description of this species has been accepted for publication in the Queensland Herbarium journal Austrobaileya.

Fieldwork has also uncovered a new record for NSW with colonies of U. subulata, previously only known to occur in northern Australia, found in the Royal National Park south of Sydney, and on the south coast near Ulladulla. Further fieldwork and genetic studies will reveal whether or not these colonies represent native or naturalised populations.

 

 

 

 

Richard-Jobson

Richard explores habitat

U. blackmanii
U. blackmanii from Undara lava field, North Qld

U.-Mt_Gambier
U. sp. ‘Mt Gambier’ from South Australia.

U.corneliana
U.corneliana from the only known location west of Tully, Qld.

Photos: R Jobson,  DE Murfet.