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TORTOISE BEETLES AND RELATIVES

CHRYSOMELIDAE: CASSIDINAE

C

assidinae was recently expanded to include

the Hispinae, which were formerly treated as

a subfamily in their own right. Cassidinae is a large,

cosmopolitan group of plant-feeding beetles within

the leaf beetle family Chrysomelidae.

The true tortoise beetles, the tribe Cassidini,

are named for their tortoise-like shape. They can

defend themselves by clamping down on a leaf

surface using specialized pads on their feet, which

makes it difficult for a predator to dislodge them or

to access their vulnerable underside. Many species

show advanced parental care, where the

mother protects the eggs in this way from

predators and parasitoids such as ants

and parasitic wasps. As the larvae grow,

the mother continues to protect them

until they are ready to pupate. Some

species are green or brown to

camouflage with their host plants,

or to resemble spots of mildew

on the leaves. Others are brightly

colored to indicate that they are toxic

or distasteful, having accumulated

chemicals from host plants. Some

tropical species are glittering metallic gold

or silver, imitating droplets of water on leaves,

an effective defense in a wet tropical rainforest.

The Hispini have different defenses: some are

armed with formidable spines that would make most

birds or amphibians think twice about eating them.

These are a primarily tropical group, but several

species occur in Europe and North America, many

of which are leaf miners in the leaves of various

grasses, palms, and other plants.

subfamily

Cassidinae

known species

6,000–7,000

distribution

Worldwide except Antarctica

habitat

Tropical rainforests to parks, roadsides,

and gardens

size

2–35 mm

diet

Adults and larvae feed on leaves, many

species are host-specific on only a single

genus or species of plants

notes

Larvae of true tortoise beetles (tribe Cassidini)

have moveable spines at the tip of their

abdomen that they hold over their back like

an umbrella, and on which they collect their

own droppings as a means of camouflage

and protection. This mobile defensive

structure is called a “fecal shield”

CHRYSOMELIDAE: CASSIDINAE