Small World Discoveries

HEMIPTERA > HETEROPTERA > PENTATOMORPHA > COREOIDEA > Stenocephaidae

A small family that is represented in Britain by just two 'nationally scarce', spurge-feeding species that superficially resemble Coreidae leatherbugs.

Despite their size and slightly different form, the general appearance is very similar, which could make them difficult to separate if found in the same area which, fortunately, is rather unlikely as, apart from the fact that they are not at all common, they occur in completely different habitats. They are brown-coloured with a heavily punctured thorax, scutellum and forewings, a connexivum with spaced yellowish spots, and banded four-segmented antennae that can help with identity.  

Dicranocephalus agilis is the larger of the two with a slightly more elongate form and a body length that's typically around 12-14mm. It's a coastal species that is largely confined to sand dunes in the south and south-west where it is specifically associated with Sea Spurge and Portland Spurge, which has resulted in the common names of either the Sea or Portland Spurgebug. Adults overwinter, usually emerging and mating in May, with the new generation appearing from August onward. According to the NBN Atlas, there are nearly three times as many records for Dicranocephalus agilis as there are for Dicranocephalus medius; 318 compared with only 116 at the time of writing. There are only nine from Dorset, but one of those was in July 2022 from Portland.

Dicranocephalus medius averages a bit smaller at 8-11mm, which gives it a broader and slightly more rounded appearance. It has been recorded from both central and southern England but, as previously noted, there are a very few confirmed records, with only two coming from Dorset in the past twenty-five years! It occurs in woodland clearings where it feeds on Wood Spurge, although in recent years there have been a few records from non-native spurges or spurge hybrids that suggest the bug is having to widen its host range. Given their natural habitat and preferred foodplant, Dicranocephalus medius is commonly known as the Wood Spurgebug.