The deroceras are a genus of slugs represented locally by two species, one of which could be endemic to the Maltese islands.

The genus consists of about 123 species of small to medium terrestrial slugs. Most species are between 30 and 35 millimetres long. Their colours vary both within and between species, ranging from pale cream with darker flecks, to light grey, brown or black-brown.

One of the two species found locally was first described in 1962 and given the scientific name Deroceras golcheri. This species was believed to be found only on mainland Malta but it has since been found on the island of Montecristo, which forms part of the Tuscan Archipelago. The Montecristo population could have been introduced there from specimens carried by humans from Malta.

Deroceras golcheri can be found in both natural and modified habitats such as gardens. It prefers sites with trees, shrubs or dense undergrowth and is usually found under stones, and other debris.

This species was believed to be found only on mainland Malta but it has since been found on the island of Montecristo, which forms part of the Tuscan Archipelago

It is quite rare and can be confused with the more common Deroceras panormitanum. There needs to be more research to determine the golcheri’s relationship with other species of deroceras that are found in the Mediterranean and mainland Europe.

Deroceras panormitanum is a very common species that lives in the same areas, preferring dark damp places such as under stones and wood. It is common in greenhouses and vegetable gardens and can become a pest. It was originally restricted to Sicily and Malta but has been introduced in Mediterranean Europe, in central northern Europe, as well as in countries beyond Europe.

Four other species of slugs have been recorded in the Maltese islands.

They are mostly active in the cooler and wetter months, but in irrigated areas they can be active during the night even in spring.

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