Cassidinae: Fascinating little beetles
Tortoiseshell beetles constitute a fascinating group of small beetles belonging to the Cassidinae subfamily of the Chrysomelidae family. This group includes some 2,500 species, which mainly live in the tropics, although ten or so are found in Québec. They are known as tortoiseshell beetles due to the round or oval shape of their wing case and the fact that they often retract their head under their pronotum, like a turtle pulls its head into its shell to protect itself.
The colouring and patterns on these magnificent insects vary greatly; green, gold, red and yellow are found on many species. With their hard wing cases and metallic beauty, some species are used to make jewellery, such as earrings. Recent discoveries have shown that many species of tortoiseshell beetle can change their colouring and patterns throughout their lives, depending on their age and diet. They are plant-eating insects, and many species can cause damage to various plants. The larvae carry pieces of shed exoskeleton (exuviae) and feces at their posterior end, providing good camouflage and forming a kind of shield to protect them from predators.
Systematic research in the Insectarium’s scientific collection
Through work carried out in the Insectarium’s scientific collection in cooperation with a Polish specialist at the Biodiversity Centre and with the arrival of new material from from Peru, two new species were discovered in the collection in late 2012. The first, from India, was named Notosacantha bertounesquei (Borowiec and Le Tirant, 2012) in honour of a friend: painter and great collector of insects André Bertounesque, whose family donated his collection to the Insectarium when he died.
The other species, from Peru, is Stolas flavoradiata, whose holotype will be preserved in the Insectarium’s collection. The holotype is the first specimen used to name a new species; the specimen voucher. The Insectarium’s scientific collection now includes over 500 species of beetle and some 20 paratypes (other specimen vouchers).