A Tale of Two Bugs

November’s guided walk at NWT Thorpe Marshes was on a lovely mild morning. Stonechats are overwintering on the reserve for the third time and both of the pair showed well for the group of 20 people. However winter birds, such as ducks on the gravel pit, St Andrews Broad, were all but absent.

The riverside footpath isn’t always the nicest with some muddy patches, but it feels sheltered and lush. Keen eyed group members found two interesting bugs tucked into the stinging nettles and white dead-nettles.

I guess any experienced bug observer would know them, but I couldn’t name them straight away and that feels like a good reason to share their names and pictures. Much as most of us would know blackbirds and chaffinches, or red admirals and large whites, common bugs feel like a learning curve worth tackling.

Thorpe Marshes regular Susan Weeks showed herself to be that experienced bug observer and came up with the right IDs on the spot. Well, I was impressed.

The red and black bug is Corizus hyoscyami, a scentless plant bug called 'cinnamon bug' or, rather simply, 'black & red squash bug'. I don’t recall seeing it at Thorpe Marshes before. In East Anglia it should be an easy one to remember. Not so once you get into Europe. Have a look at all these rather similar red and black bugs.

The shield bug is hairy shieldbug Dolycoris baccarum, also known as sloe bug (e.g. in Chinery’s Pocket Guide to Insects) though that name is waning as it seems to be a misnomer with no link to sloes or blackthorn. The black and white antennae are easier to observe than the bug’s hairiness.

Even without the right field guides, help is easy thanks to online sources. These two are good: Norfolk & Norwich Naturalists’ Society's Shield Bugs of Norfolk and, across the river from Thorpe Marshes, James Emerson’s Shieldbugs & allied insects of the Whitlingham area. Bear in mind that larval forms of bugs can look quite different to adults.