An insect pest that wrought havoc in the California fruit industry two decades ago has made its appearance in the Western Cape, a University of Stellenbosch entomologist announced on Tuesday.

Professor Jan Giliomee recently discovered the pomegranate or ash whitefly for the first time in South Africa on a wild olive on the Overberg coast, and it was then formally identified by a taxonomist of the National Insect Collection in Pretoria.

The whitefly originates in Mediterranean countries and has spread to India, Iran, New Zealand and Australia.

Giliomee surmised that the whitefly entered the country with plant material that was not quarantined.

He said the pest was bought under control in California only after parasites were imported.

"It must now be established whether wasps that prey on the pest are present here and, if not, they must be imported," he said. - Sapa