First record of an indigenous South African parasitoid wasp on an imported biological control agent, the water hyacinth hopper

ABSTRACT

Water hyacinth, Pontederia crassipes (Martius) [≡Eichhornia crassip es (Martius) Solms-Laubach] (Pontederiaceae), is native to South America, but has expanded its range to many other regions of the world including South Africa. Megamelus scutellaris Berg (Hemiptera: Delphacidae) was released as a biological control agent and has established in several regions. Recently, the indigenous species Echthrodelphax migratorius Benoit, (Hymenoptera: Dryinidae) was discovered in South Africa parasitising M. scutellaris. This newly discovered relationship might have repercussions for the efficacy of biological control of water hyacinth by the delphacid. The wasp may negatively impact M. scutellaris populations making it difficult for the agent to successfully manage the invasive weed. Contrarily, the parasitoid may be beneficial by keeping the M. scutellaris populations stable, serving as a natural enemy.

KEYWORDS:

• Megamelus scutellaris
• Echthrodelphax migratorius
• plant-insect interactions
• Pontederia crassipes

Acknowledgement

This research was funded through the Department of Environmental Affairs, Natural Resource Management Programme’s Working for Water programme. Further funding for this work was provided by the South African Research Chairs Initiative of the Department of Science and Technology and the National Research Foundation of South Africa (grant nos. 89967, 109244 and 109683). Simon van Noort was funded by a South African NRF FBIP grant no 98115.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Emily C. Kraus http://orcid.org/0000-0003-3744-4249

Julie Coetzee http://orcid.org/0000-0002-0364-3349

Simon van Noort http://orcid.org/0000-0001-6930-9741

Massimo Olmi http://orcid.org/0000-0001-5953-5075

Additional information

Funding

This work was supported by South African Research Chairs Initiative of the Department of Science and Technology and the National Research Foundation of South Africa: [Grant Number 89967, 109244, and 109683]; South African National Research Foundation: [Grant Number GUN 98115]; Department of Environmental Affairs, Natural Resource Management Programme’s Working for Water programme.