Australian Tropical Herbarium Research and Programs Theme 3 –Biodiversity in a Changing World

Theme 3 –Biodiversity in a Changing World

Assessing the taxonomic status of threatened species using genomic data

Taxon delimitation in closely related, recently evolved plant species is often challenging, and phenomena such as hybridisation and introgression among closely related species may blur taxonomic boundaries. In such cases, traditional methods such as morphological analyses or molecular analyses based on a small number of standard genetic markers are often unable to reliably delimit species boundaries. Yet, the recognition of genuine species is crucial for the development and implementation of an effective conservation strategy, and ensures that the limited resources available for plant conservation are used most efficiently. This project aims to clarify taxonomic boundaries of threatened species with doubtful taxonomic status using genomic data. This conservation genomic project uses next generation sequencing approaches yielding a high number of genetic markers distributed throughout the genome, such as RAD-sequencing, and will allow for a robust re-assessment of the taxonomic status of threatened plant species as well as their conservation status.

Team

Lars Nauheimer (ATH), Katharina Nargar (ATH), Mark Clements (CSIRO)

Team

Darren Crayn (ATH), Stuart Worboys (ATH), Sue Gardiner (Plant and Food Research, New Zealand), Marion McKay (Massey University).

Ex-situ conservation of collector-targeted Vulnerable and Endangered plants of the Wet Tropics and offshore Oceanic Islands

Many species of ferns, lycophytes, orchids and epiphytes are highly endangered from the compound threats of climate change, habitat loss, extreme natural rarity and being targeted by rare plant collectors. This project explores the feasibility of ex-situ propagation and conservation of a suite of highly threatened plants from the Wet Tropics and from offshore Oceanic Islands with the view of establishing either in-botanic garden or in-trade conservation reserves. These could be reserves from which reintroduction into the wild could be implemented following local extinction of a species. Several species being studied include Myrmecodia beccarii (Ant-house plant), Oberonia attenuata (Mossman Fairy Orchid), Phalaenopsis amabilis (Moth-Orchid), Pronephium sp. nov. (Russell River Fern), Phlegmariurus pinifolius (Gold-tip tassel fern) and ferns from Christmas Island, Lord Howe Island and Christmas Island.

Team

Ashley Field (ATH), Caroline Chong (ANBG), Melinda Greenfield (JCU).

Saving the unique plants of Australia’s tropical mountain tops

Climate niche modeling of plant species endemic to Wet Tropics mountaintops (> 1000 m elevation) indicates that the extent of habitat of these species will decline catastrophically by 2080 such that they may qualify as Critically Endangered (IUCN Red List criteria). Following successful completion in Sept. 2017 of the first stage of this project – extensive surveys for additional wild populations - funds for a more substantial project were obtained in late 2018. This project aims to secure the future of these plants by building a multi-strategy ex-situ conservation reserve to ‘backup’ at-risk wild populations and support research, display and education. Novel research on seed banking strategies (undertaken by partner investigators), genetic diversity and plant tolerance of extreme climates (undertaken by partner investigators) will ensure that the reserve collections, distributed across multiple Botanic Gardens and Seed Banks along Australia’s east coast, incorporate high redundancy, are genetically and physiologically diverse, and climatically matched to wild habitat.

Team

Darren Crayn (ATH), Stuart Worboys (ATH), Lucas Cernusak (JCU), Alex Cheesman (JCU), David Warmington (Cairns BG), Greg Bourke (Blue Mountains BG), Maurizio Rossetto (Royal BG Sydney), Karen Sommerville (PlantBank, Royal BG Sydney), David Taylor (Australian National BG), Lydia Guja (Australian National Seed Bank), Andrew Rouse (Dandenong Ranges Botanic Garden), Warren Worboys (Royal BG Victoria), Donna Davis (visual artist).

Improving conservation outcomes for pitcher plants by resolving controversies in their taxonomy and understanding their evolution

The carnivorous pitcher plant genus Nepenthes comprises c.160 species distributed throughout Southeast Asia and Oceania. Species have traditionally been distinguished using morphological characteristics, but many recently described species have been distinguished on the basis of minor differences, whose stability has been questioned. To date, no taxonomically informative molecular phylogeny of Nepenthes has been published. The lack of an objective taxonomic framework has hindered the efforts of biologists who seek to study and conserve threatened Nepenthes. This study seeks to eliminate this problem using next generation sequencing methods to construct a robust, informative phylogeny of Nepenthes based on c. 100 species.

Team

Darren Crayn (ATH), Katharina Nargar (ATH), Charles Clarke (ATH Adjunct), Lars Nauheimer (ATH), Lujing (Louise) Cui (CSIRO vacation scholar), Nick Weigner (JCU Honours student).

Recovery of the critically endangered purple wattle, Acacia purpureopetala

The Purple Wattle (Acacia purpureopetala) has a very restricted range, occurring only in the Herberton district of the Einasleigh Uplands bioregion. In 2009 it was estimated that only 10 populations containing 500 mature plants remained over an area of less than 50 Ha, and those populations appeared to be in decline.  To date, no-one has successfully propagated the plant from seed.

The Mbabaram are the Traditional Owners of all known Purple Wattle habitat. Through this project, Mbabaram TOs will direct and manage a species recovery project on their land. Project activities will include identification of critical habitat parameters to inform modelling of suitable habitat, surveys for further occurrences and collecting of material suitable for propagation and research, and engagement and awareness raising with non-Indigenous land managers. A principal outcome will be a 5 year recovery strategy for the species.

Team

Mbabaram Traditional Owners, Watsonville Aboriginal Corporation, Northern Gulf NRM, Gerry Turpin (ATH).