Tag Archives: Doros profuges

The Jones index of implied menace

US entomologist Justin Schmidt has carved out a place in entomological history by putting together the Schmidt pain index to measure the intensity of insect stings. These range from a score of 1 the tickle of sweat bees (Halictus species etc) to 4 the kind of pain that makes you lie down and scream (bullet ant, Paraponera clavata). The pain index is referenced throughout the internet, but this is the Natural History Museum’s take on it.

Not wanting to be outdone I’ve decided to launch the

This is the opposite of a pain index, because none of the insects has a sting. They just look threatening.

It seems obvious now, that stinging or poisonous models might be copied by harmless mimics, to trick potential predators into thinking that they were painfully dangerous, but it wasn’t until naturalist and explorer Henry Walter Bates formalized it in 1861, that the idea gained widespread understanding. It is now known the biological world over as Batesian mimicry.

The Jones index of implied menace is an irreverent unpicking of Bates’s mimicry, aligned on a scale from Woah! to Oh how cute. At menace level 4 even the hardened entomologist might take a step back and stand cautiously for a moment or two as they size up the target insect. Menace level 1 just brings a smile to your face and the thought: “What pretty colours”. Even more so than Schmidt’s pain scale, my index is subjective in the extreme. But it works for me.

4. Hornet robberfly, Asilus crabroniformis.

Damn this thing looks pure evil.

 

Arguably Britain’s most striking fly, the hornet-mimicking Asilus crabroniformis. Taken from its well-deserved place on the frontispiece in Colyer & Hammond’s (1951) Flies of the British Isles.

3. Hornet moth, Sesia apiformis.

A moth? Really? Are you sure?

The hornet moth, Sesia apiformis, is one of the clearwings, named for their narrow, transparent, unscaled and unpatterned wings which make them not at all moth-like, but very wasp-like, very wasp-like indeed.

2. Phantom hoverfly, Doros profuges.

Sleek, but with that sinister-looking narrow waist and menacingly darkened wing edges….

The ‘phantom’ hoverfly, Doros profuges. I’ve filched this as a screenshot from the excellent diptera.info website; I hope they don’t mind.

1. Ant beetle, Anthicus floralis.

Looks a bit like an ant — if you squint.

Anthicus floralis does look remarkably ant-like when it runs about at top speed on the ground. But it’s hardly a thing of nightmares.

Like Schmidt, I’m prepared to allow some latitude, breaking out from the 4-point scale, when necessary. The brightly coloured craneflies, Ctenophora, look creepy as well as being threateningly coloured, enough to score 3.5 maybe.

For some people the creepy long legs do it, for others it’s the intimidating upturned spike of a tail. But, like all craneflies, a female Ctenophora pectinicornis is completely harmless.

Most hoverflies would rank 1, although I might make an exception for Volucella zonaria, and give it a 3, if only because of its menacing size.

Even dead in the hand it looks unnerving — Britain’s largest hoverfly, Volucella zonaria.

On the other hand conopids, which are visually superb wasp mimics actually look too cuddly, so only get 2, except for Sicus ferrugineus which, with its curled can-opener tail, looks a very sinister 2.7.

The brightly coloured wasp longhorn, Rutpela maculata, scores 2 when it walks, but a waspish 3 when it flies.

The wasp longhorn, Rutpela (Strangalia) maculata is a frequent flower visitor and does that hawking bobbing flight so characteristic of wasps.

So next time you stare in wide-eyed startlement at some large buzzing bug, beetle or fly, which you first thought was a wasp, but now realize is a mimic, remember to take a moment during your stand-down relaxation to ask yourself the question: “Yes, but what Jones score did it elicit?”

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No wonder Mr Darwin was so pleased

Thirty years before On the origin of species was published, Charles Darwin’s first appearance in print was, he later confessed, still one of his proudest achievements. You see, like so many great biologists, Darwin was a beetle man at heart.

In his later days  he likened himself to an old war horse, roused by a clarion call, on reading of the discovery of rare beetles. Well, that really rings true. He also said that seeing his name next to some of the beetle records in James Francis Stephens’ milestone 12 volumes series of  Illustrations of British Entomology (1828-1846) brought him great delight, and well it might.

Just one of several of Darwin's beetle finds, recorded in Stephens' monumental Illustrations of British entomology.

Just one of several of Charles Darwin’s beetle finds, recorded in the first beetle volume of J.F. Stephens’ monumental Illustrations of British entomology.

Here it is, in the addenda to Stephens’ first beetle volume (1829). Since it was issued in parts, various subscribing entomologists were able to read the early fascicles and send their comments and additional records to the author so he could incorporate them before the volume was finished. Technically, Darwin’s first record is a couple of pages earlier, but was for what is now a non-species (Ocys tempestivus, which has since been synonymized as just a slightly larger and brighter form of the very common Ocys harpaloides).

Blethisa multipunctata is a beautifully sculpted metallic ground beetle from riversides and marshes. Studying at Cambridge, Darwin was well-placed to find it in the Cambridgeshire fens, still a major stronghold. I’ve never found it. If I did, I’d certainly let someone know. And hope to see my record in print, with my name beside it.

When I was eighteen, I went up to an entomological meeting at London’s Natural History Museum. Here were many of the well-known entomologists of the day, Cyril Hammond was one I remember. I chatted to a few people, including the dipterist Alan Stubbs, one of the organizers, who was singularly impressed to learn that I had just recently seen quite a lot of a strikingly handsome and very rare hoverfly, Doros profuges (D. conopseus it was then). Later, when addressing the meeting he made mention of me, a newcomer in the room who had seen more specimens of this scarce fly than all previous British entomologists put together. There was a lot of interested head nodding in the audience, and I felt the same pride that Darwin knew. I guess that makes me a fly man, as well as a beetle man.