Length 3.5-4.5 mm. Front margin of head strongly notched; outer margin of fore-wing pale over the whole or most of the length of the corium (c.f. Legnotus picipes). 

The much rarer Legnotus picipes (Heath Shieldbug) is similar, but is scarce in the UK, and mainly in the SE; it has not yet been recorded in Leicestershire and Rutland.  The basal edge of the corium of L picipes is pale and the central lobe of the head is the same length as the outer two (clearly shorter in L. limbosus).
Could be confused with Sehirus luctuosus, Forget-me-not Shieldbug, but this is larger, 7-9mm. 

Associated with bedstraws (Galium sp) growing on dry friable soils in sunny situations, frequently burrowing into loose soil at the base of the foodplant.

Adult: All year.

Widespread in southern Britain, but unobtrusive, becoming scarcer further north and absent from Scotland and Ireland.

Infrequent or little recorded in Leicestershire and Rutland