The devil's coach-horse beetle

The devil's coach-horse beetle is common and widespread in the Maltese countryside but not often seen because it is mostly active at night. It is found in most of Europe and has also been introduced to the Americas and parts of Australasia.

It belongs to a large family of beetles known as the rove beetles. Members of this family have short forewings, which cover only half the abdomen. The exposed abdomen is protected by hardened plates.

The devil’s coach-horse beetle can and sometimes does fly but when threatened it prefers to raise its abdomen like a scorpion and to open its jaws. This explains its Maltese name Katarina għolli denbek. In English speaking countries it is sometimes also called cock-tail beetle.

The sting has no poison but it can give a painful bite with its strong jaws. It can also secrete a foul smelling liquid from a pair of glands found at the end of its abdomen.

It feeds on other invertebrates such as insects and spiders as well as on carrion.

The specimen I photographed early in the morning was feeding on the remains of a snail that had been trodden upon by somebody a few hours earlier. When feeding it cuts its prey into small pieces with its mandibles and moulds them into a spherical shape using its front legs. It then chews and swallows then regurgitates it covered in a brown liquid which digests the material. When the solid material is completely liquefied swallows it. The larvae have similar eating habits.

In many parts of Europe this beetle has been associated with the devil since the Middle Ages. In Ireland it was believed that the devil takes the form of this beetle to eat sinners. It was supposed to bring bad luck and people could turn this to their advantage to acquire power over others.

This article was published in The Times on 25 November 2009.