Scutelleridae

Tortoise Shieldbugs

HEMIPTERA > HETEROPTERA > PENTATOMORPHA > PENTATOMOIDEA > Scutelleridae

In this family the scutellum is so large that it extends to the tip of the abdomen, almost entirely covering the wings, and giving rise to the collective common name of tortoise shieldbugs. There are four extant species, two rare Odontoscelis streaked shieldbugs, and two Eurygaster tortoise shieldbugs.

The Tortoise Shieldbug [Eurygaster testudinaria] is now reasonably common and widespread across much of the south, whereas the slightly smaller Scarce Tortoise Shieldbug [Eurygaster maura] is much rarer. The generally brown, although sometimes reddish, ground colour and darker mottled markings are variable so distinguishing the species comes down to fine details, the most reliable being the shape of the front of the head. In Eurygaster testudinaria there's a slight, but apparent central depression, which is perhaps more discernible when directly comparing the two species as the shape is distinctly more rounded in Eurygaster maura. The two species are often confused, but looking at the individuals featured here I'm pretty confident that they've been correctly identified. The length of the third antennal segment is another indicator, but it's so marginal that you'd need a specimen or an extremely well detailed photo. Similarly with the form of the hind corners of the pronotum where in Eurygaster testudinaria they are said to be typically, slightly more protruding, but to see the detail clearly you need a shot from directly overhead and not from an angle which can be misleading.

The nymphs, which are equally variable, are normally defined as being early, mid or late/final instars. They may be found feeding on grasses and rushes from May to July/August. The fully developed adults can be seen through to September.