The leaf beetle is a member of an insect family populated by around 60 species in Malta.

The picture shows one of them, known in Maltese as żabbella, a name that was also used for ladybirds. The scientific name which distinguishes this beetle from all other leaf beetles is Chrysolina variolosa.

This species is frequent although not common and usually found on the spiny asparagus, (spraġġ in Maltese) as it eats its leaves.

But the specimen I photographed last Sunday at Mistra Bay was walking on rocks a long way from any asparagus plant.

The leaf beetle family is the largest and most commonly encountered beetle family.

There are over 35,000 species in this family alone and several of them are of economic importance because of their impact on agricultural produce.

Some have been used to control weeds biologically especially in Australia and in California.

But the greatest impact is probably that of another species – the Colorado potato beetle which can devastate entire crops of potato.

It is indigenous to the Americas but it was not until 1840 that it started to become a pest of the potato plant.

The Colorado potato beetle appeared in Germany in 1877 but was soon eradicated from that country. It reappeared in Europe sometime during World War I and was first seen near American military bases in Bordeaux. From there it spread to Belgium, The Netherlands and Spain eating its way through potato fields.

Soon after the Colorado potato beetle started to spread in Europe, the Maltese Government prohibited the importation of crops from any areas where it was present and managed to keep the Maltese islands free from this pest.

In 2008 the EU issued a directive and Malta was declared a protected zone leading to special measures such as plant quarantine to keep the Colorado potato beetle away from the islands.

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