Country diary: A riot of colour and cannibalism | Mark Cocker

Her appearance was so unexpectedly brilliant that when I spotted a 1cm squirt of colour land on the ground an arm’s length away, she seemed more like a momentary flicker of flame. Then she went out and I was in agonies to relocate her.

Even on that briefest view, she was easily among the brightest insects I’ve seen. I also got some of the improbable range: the shimmering emerald, the rich purple thorax, glittering magenta on her abdomen and, at the rear, a cone of deepest, darkest blue. When she finally returned and I could examine her at leisure, I realised that the thorax had the same unlikely tone as ripened lychees, even to the exact dimpled quality of the fruit’s surface.

Weirdest were her turquoise antennae, outstretched, a third longer than her limbs, jointed and angled so she could touch the ground as she walked. The intent, downward inflection of her action lent this multicoloured cuckoo wasp (for I learned later that this was her name) a rather myopic, deeply absorbed, even bookish, quality as she went tap-tap-tapping across the sand.

Related: Country diary: The living is easy for these summertime insects

Who knows what exquisite sensitivity resides in their sensory tips, but she was soon acting on a signal. There were clues that even I could detect, because the substrate was pocked with minute burrows, whose entrances bore raised tubes of hardened sand like miniature chimneys. These are almost certainly the works of mason wasps. The owners dig out nest chambers and provision their intended offspring with fresh meat, such as flies and caterpillars, stung and thus paralysed, but not dead.

The cuckoo (technically named Chrysis viridula ) enters the nursery of these other wasps and lays her own eggs. On hatching, the children of the cuckoo wasp eat the food provisions and probably the other wasps’ larvae, before emerging in spring.

If caught underground, in flagrante delicto, while performing this murderous malarkey, an adult cuckoo wasp can curl up into a hedgehog’s ball and her hard, brassy, lychee-coloured carapace protects her from a mason wasp’s sting. It strikes me that this tiny insect is like all life itself – mysterious, beautiful, completely improbable and, ultimately, full of remorseless terror.

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