Beth Grobbelaar, a leaf beetle taxonomist at the Biosystematics Division of the Agricultural Research Council’s (ARC) institute of Plant Health and Protection, has collaborated with specialists at the National Research Council of Italy’s Institute for Sustainable Plant Protection, regarding the characterisation of Lema bilineata (Germar), a new alien invasive species in Europe.

Species also invasive in South Africa

Following its introduction into Europe, the beetle was positively identified by Michael Schmidt, a German systematist specialising in the subfamily Criocerinae. Native to South America, the beetle is also invasive in South Africa, having likely been introduced from Argentina in horse feed during the Anglo Boer War. It subsequently spread to Zimbabwe and Australia.

To effectively distinguish it from Lema daturaphila Kogan & Goeden, a related species with a similar host range and invasion history in South Africa, a better understanding of the characterisation of the two species was required. To achieve this, photographic images of specimens from both Italy and South Africa were produced. Specimens were also subjected to molecular analyses. The images and analyses elucidate the chromatic and other variations within L. bilineata.

Aim is to recognise, prevent new introductions

The information, as well as data of the closely related alien invasive species L. daturaphila, was first presented at the 11th European Congress of Entomology in Italy in 2018. Final collation of the research data was then disseminated in the collaborative publication Morphological and molecular characterisation of Lema bilineata (Germar), a new alien invasive leaf beetle for Europe, with notes on the related species Lema daturaphila Kogan & Goeden.

The published data will provide a means of efficiently recognising these beetles at points of entry, thus preventing potential new introductions, and will facilitate prompt implementation of eradication measures.

For more information, contact Beth Grobbelaar at GrobbelaarB@arc.agric.za. – ARC-Plant Health and Protection newsletter