Tag Archives: Drilus flavescens

Hallelujah — a beetle larva to bring me to my knees

Apparently I let out a triumphal cry and sank to my knees to greet this wonderful creature — the bizarre, secretive larva of Drilus flavescens. I’ve never seen one before, but instantly knew it from photos that other people had taunted me with. And it features on the cover of the newly published Royal Entomological Society handbook on beetle larvae. Click on the photos to see the Youtube videos we took of it rippling along the South Downs Way near Plumpton Plain just west of Lewes.

Drilus larva undulating along the South Downs Way behind Falmer, East Sussex, 11.viii.2019. Click on the picture to see my Youtube video of it rippling about.

Drilus is a snail predator. The feathery appendages are a protection against it getting mired in the snail’s copious defensive slime. Click on the picture to see another Youtube video of it galumphing along the path.

The beetle is rather local, on chalk downland in southern England. At least the male is. It looks just like a beetle — its wing cases are brown, its head and thorax are black, and its long feathery antennae are very distinctive. It flies readily and I’ve caught it in my bare hands in my parent’s garden at the foot of the South Downs in Sussex. The female, on the other hand, is a flaccid bag of eggs, lacking wings or wing-cases and weighing 50–100 times as much as a male. On 18 June 2003 I was similarly brought to my knees by this beetle when I found a mating pair walking across the footpath at High Elms, near Downe in Kent. 

Sexual dimorphism at its most extreme? At the time I thought this was likely to be the first photograph ever taken of Drilus flavescens mating.

Entomology is one of the most fascinating studies in the world. There is always something new to see, to discover, to get excited about. I thrive on what some people might call a childish enthusiasm. And it makes me smile.

Treasure. Look at that grin.