The Acanthosomatidae are a family of shieldbugs, belonging to the order Hemiptera (the true bugs). This family includes around 54 genera and 200 species found in many parts of the world, with several species present in Europe and a few in the UK.

Members of this family are broad, flattened bugs with the characteristic shield-shaped body common to many shieldbugs. They are often green or brown in colour, sometimes with bright markings, and have five-segmented antennae, which help to distinguish them from similar families.

Like other shieldbugs, acanthosomatids feed by piercing plant tissues with their beak-like mouthparts to suck sap. Most species live on trees, shrubs, or herbaceous plants, where both adults and nymphs feed on leaves, fruits, or seeds.

One of the most familiar species in the UK is the Parent Bug (Elasmucha grisea), named for its remarkable parental care. Females guard their eggs and newly hatched nymphs, protecting them from predators — a rare behaviour among insects.

Shieldbugs in this family are most often seen during the warmer months, basking in sunlight on foliage. In autumn, adults may seek shelter under bark or leaf litter to overwinter.

Though sometimes regarded as minor plant pests, most species cause little harm and are an important part of woodland and hedgerow ecosystems, contributing to biodiversity and serving as food for birds and predatory insects.