Tag Archives: Ogcodes pallipes

A spider-eating fly is nearly as good as a man biting a dog

According to my in-depth research on Wikipedia just now, the man-bites-dog aphorism about news-worthy stories has been attributed to several media magnates and journalists. No dogs were bitten in the writing of this blog, but I suspect very many spiders were eaten by flies.

This is the fly that made the news.

The microcephalic hunchback that is Ogcodes pallipes.

The microcephalic hunchback that is Ogcodes pallipes.

Look at the dark-edged squama on that thing.

Look at the dark-edged squama on that thing.

 

 

 

 

 

 

 

It’s a strange-looking creature, with the semi-official but not very politically correct English name ‘black-rimmed hunchback’. I’ve never come across a member of the bizarre spider parasitoid fly family Acroceridae before. They (three UK species) all appear to be widespread, across southern England at least, but they are very scarce, and records are few and scattered. Not having functional mouthparts means the adults are short-lived, probably only surviving for a few hours or days.

I’m left wondering why the small head? Perhaps it’s like a jumbo jet, the cockpit remains the same size no matter how much you enlarge the fuselage. In the case of the fly the body of the female (which this is) is simply an egg manufacturing and storage facility, with up to 4000 microscopic eggs being laid by a related non-British species. The tiny (0.3 mm) larvae actively seek out spiders to parasitize, and of course a fly that attacks spiders is definitely news-worthy.

And here is the news that it made:

Screen Shot 2016-07-18 at 06.47.24

I had my picture taken with the mayor too, but London Wildlife Trust wisely decided I was the least photogenic member of the cast and edited me out in favour of the hunchback.