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Cat's claw creeper (Dolichandra unguis‐cati), native to tropical South America, is a major invasive species and a target for biological control in Australia, South Africa and some South Pacific Island countries. Native range surveys in Argentina, Brazil, Paraguay and Venezuela have identified eight insects and four fungal pathogens as potential agents. Five leaf‐feeding insects a tortoise beetle Charidotis auroguttata, two tingids Carvalhotingis visenda and C. hollandi, a leaf‐tying moth Hypocosmia pyrochroma and a leaf‐mining beetle Hedwigiella jureceki, have been tested and all were released in South Africa. Four of these have become established but are not widespread and cause only limited damage. In Australia, only three of these, C. visenda, H. pyrochroma and H. jureceki were released, while C. auroguttata was not approved due to perceived non‐target risks. All agents have become widely established, except for H. pyrochroma which is restricted to riparian corridors in southeast Queensland. In South Africa, an accidentally introduced leaf‐spot pathogen, Neoramulariopsis unguis‐cati, causes necrotic lesions and premature abscission of leaves in cat's claw creeper infestations, resulting in widespread defoliation. Based on its impact and field‐host specificity in its native range and in South Africa, the pathogen has been prioritised for evaluation as a potential additional agent in Australia. The current priority is to seek approval for the introduction of this leaf‐spot pathogen into Australia. Future research should focus on the gall‐inducing rust Uropyxis rickiana and the seed‐feeding weevil Apteromechus notatus as prospective agents. [ABSTRACT FROM AUTHOR]

Cryptostegia grandiflora and C. madagascariensis (Apocynaceae) are the only two species of this Madagascan plant genus. Both have been transported around the world as ornamentals due to their attractive flowers and based on a perceived potential as sources of rubber - hence, the common name rubber vine - because of their copious latex, which also contains toxic cardiac glycosides. As a result of their vigorous growth and ability to climb over and smother vegetation, both species have become invasive, posing an actual or potential threat to native ecosystems in many tropical and sub-tropical countries, as well as to human and animal health. Classical biological control (CBC), or the introduction of co-evolved natural enemies to control an invasive alien species in its exotic range, has successfully been used to tackle C. grandiflora in northern Queensland, Australia. This strategy is currently being evaluated for its suitability to manage C. madagascariensis in north-eastern Brazil using the same Madagascan rust fungus, Maravalia cryptostegiae, released as a CBC agent in Australia. For CBC to be successful, it is critical to understand the taxonomy of the invader as well as the origin(s) of its weedy biotype(s) in order to select the best-matched co-evolved natural enemies. Based on an exhaustive search in published and unpublished sources, we summarise the taxonomy and uses of these rubber vines, follow their historical movements and track their earliest records and current weed status in more than 80 countries and territories around the world. [ABSTRACT FROM AUTHOR]

Navua sedge (Cyperus aromaticus) is an aggressive perennial sedge in pastures and crops in the wet tropical regions of Australia and numerous Pacific Island countries and territories. A biological control program was started in Australia to look for biological control agents for C. aromaticus in its native range in equatorial Africa. Surveys in Kenya, Tanzania, and Nigeria identified Cintractia kyllingae, Uredo kyllingae-erectae, and Curvularia tanzanica, as potential biological control agents. Cintractia kyllingae is currently under study at CABI, UK for its host specificity to C. aromaticus as a prerequisite for any future release in Australia. [ABSTRACT FROM AUTHOR]