any of approximately 7,000 species of beetles (insect order Coleoptera) named for the clicking noise made when seized by a predator. Most click beetles range between 2.5 and 18 mm (less than 34 inch) in length and are brown or black in colour with either little or no ornamentation. However, some tropical species are brightly coloured or luminescent. Click beetles have elongated bodies with parallel sides and bluntly rounded ends