Friday mystery object #366 answer

Last week I gave you this unwelcome visitor to the Dead Zoo to identify:

I’ve given you something very similar before, which most people mistakenly identified as being this species.

It’s in the family Ptinidae, home of several species that are considered pests, thanks to their habit of boring holes in various different materials. They all tend to look quite similar, although the shape of the pronotum (the bit between the abdomen and the teensy head) is a useful feature.

As Andy Calver and Thomas Rouillar intimated on Twitter and joe vans hinted in the comments, this particular beetle is normally associated with boring holes in carbohydrate rich substances, which can include drugs, tobacco, bread and biscuits. It’s known as the Drugstore Beetle, Cigarette Beetle, Bread Beetle or Biscuit Beetle depending on your particular interest in what it destroys. Of course, other beetles can share some of these proclivities and therefore claim some of the same names, so for clarity the scientific name is Stegobium paniceum (Linnaeus, 1758).

In museums they can tun up for a variety of reasons. Sometimes they’ll be feeding on starchy glues in book spines, they love a dried plant in a herbarium, they’ll give animal hides and museum specimens a nibble, and about the only thing they like more than poisoned grain used as rodent bait would be some biscuit crumbs.

So well done to everyone who worked it out and if you didn’t manage it then never fear, there’s always next week’s!

Friday mystery object #334 answer

Last week I gave you this unwelcome visitor to have a go at identifying:

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It’s a type of beetle – so a member of the Coleoptera or “sheathe wing” as palfreyman1414 pointed out) – in the family Dermestidae (as Wouter van Gestel intimated) and the species is Reesa vespulae (Milliron, 1939) as Tony Irwin hinted at with his cryptic clue:

Sometimes attached to a mogg, this seems to belong to a diminutive scooter

There were several other nice cryptic suggestions in the comments section, plus some on Twitter, so very well done to everyone who worked out what this was.

The species gets the name vespulae from its affinity with wasp nests, where it feeds on dead wasps and the scraps of insects that the adult wasps feed their larvae, so they’re sometimes called the Wasp-nest dermestid.

wasps

The natural target of Reesa vespulae

These tiny beetles can strikes terror into the heart of a museum curator, since they are well adapted to feed on dried insect remains (of which we have huge numbers making up our collections) and they are parthenogenic – meaning that they reproduce without mating (only females of the species are known) and just one individual is all it takes to create a full-blown infestation.

Damage caused by a Reesa vespulae infestation

Damage caused by a Reesa vespulae infestation

You can tell them apart from some of the other dermestid beetles (many of which are also museum pests) because they have ‘hairy’ elytra (or wingcases) with a lighter coloured patch on each of their ‘shoulders’ (they’re not shoulders, but you probably get what I mean).

If you find one of these wee beasts in your collection, be afraid – be very afraid!

Friday mystery object #312 answer

Last week I gave you this specimen to identify, which came in as an enquiry after being found in someone’s toilet:

There were a variety of great responses, with some fantastic cryptic clues, including an anagram by Claire Miles (great stuff!). Most opted for this being Stegobium paniceum, which is also known by the aliases Drugstore Beetle, Biscuit Beetle or Bread Beetle.

Stegobium paniceum by Sarefo, 2007

Stegobium paniceum by Sarefo, 2007

However, the mystery critter has a subtly different pronotum (that’s the plate over the thorax that extends over the head).

Another suggestion was woodworm or one of the false powderpost beetles, which covers a range of wood-boring beetles, with Liberty Hightower correctly giving the more taxonomically constrained suggestion, of something from the Tribe Anobiini (which includes Stegobium). However, my colleague Olivier sent me an email with a very definitive identification, informed by a past experience with this particular pest – the Furniture Beetle Anobium punctatum De Geer, 1774.

These beetles have a distinctive pronotum that supposedly looks like a monk’s cowl, with a more distinctive hump and slightly pinched looking back section than the more smoothly curving pronotum of the Stegobium. They fall into the broad category of woodworm because their larvae feed on wood, making tunnels hidden from view and only becoming visible when they emerge from small holes in the wood as adults, leaving a little pile of wood dust as they go.

The presence of these beetles in a toilet isn’t related to the water in the bowl or even wood of the seat – it turns out that there was a window above the toilet and the adult beetles, in an attempt to leave the building after emerging, were attracted to the light from the window and flew into the glass only to bounce off and land in the toilet.

This attraction towards light in the dispersing adult stage of the beetle is a handy behaviour if you want to keep track of these pests. If you’re concerned you may have active woodworm it’s worth checking your windowsills in the summer to see if you have any of these adult beetles lying around. Of course, there are other species that would also be worth checking for, since there are plenty of beetles whose larvae would be considered woodworm. Keep your eyes peeled!

Friday mystery object #309 answer

There are lies, damn lies and statistics* and then there are inaccurate statements made from assumptions that are based on insufficient knowledge and poor research. Last week I fell into this sort of untruth when I offered up this diminutive mystery object that I said was from Ireland:

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My excuse for that untruth is the fact that the specimen was in a part of the collection dealing with native species (which I forgot also includes British taxa, because the collection is old enough to have been split into “native” and “foreign” before Ireland stopped being part of the UK) and I’d quickly checked the distribution with reference to a handy online checklist of British and Irish Hymenoptera, but I then missed the bit under the species that said the range was restricted to England. I assumed based on context and as a result I got it wrong – and we all know that we should never ASSUME, because when you ASSUME, you make an ASS of U and ME*.

So thanks to jennifermacaire  and David Notton for pointing out my mistake – it is much appreciated. I should have checked the label for the collection locality, but unfortunately the image was taken as a snap on my phone while bagging the drawer containing this specimen (while I was preparing hundreds of of other such drawers and insect boxes as part of a major collections move) so I didn’t get the chance. This is actually a bit of a problem for digitisation when insects are pinned like this, because the label is invisible from above.

insect room

Insect boxes bagged for transport and freezing

If I was more familiar with the insect fauna of Britain and Ireland it would have helped, but as you may be aware, my main area of experience is in bones and the critters that have them, so my knowledge of insects tends to be quite generalised or restricted to particularly important or interesting species that I’ve had reason to research.

Skull of female Jaguar in the Dublin Dead Zoo

The kind of specimen I really understand

This is one of the challenges in my role as curator of Zoology and Entomology at the National Museum of Ireland, where I work with somewhere in the region of 2 million specimens, covering the whole of the animal Kingdom, from all over the world.

Normally museums with collections of this size would have a few specialist curators to focus on the main taxonomic divisions, but for the time being I’m dealing with the lot, so I have a steep learning curve to get up to speed with the whole collection. Of course, it’s well worth it, as there are some incredible specimens in there – either because of what they are, or who they were collected by and how important they are for science and culture.

Wasps collected by Charles Darwin during the Voyage of the Beagle.

Wasps collected by Charles Darwin during the Voyage of the Beagle.

Anyway, excuses aside, I expect you’re keen to find out what that small hymenopteran was. Chris very quickly identified it as one of the small, solitary carpenter bees. This is the only one that is “native” – in that it occurs in Southeast England – and even then it’s pretty rare to find it except in downlands in the South, mainly in East Hampshire.

The name is Ceratina cyanea (Kirby, 1802) and the female excavates a burrow in the stem of a dead plant, making tiny cells with walls of sawdust in which she lays eggs – hence the name “carpenter bees” for the group that shows this behaviour.

Another mystery object to come next week – this time it will hopefully be a bit less misleading!

 

*Attributed to Benjamin Disraeli, by Mark Twain

*I’m attributing that to the fictional character Dawn Summers from Buffy the Vampire Slayer because that’s where I heard it first, but it was coined by Jerry Belson

Friday mystery object #308

As I’ve mentioned before, for the last few months I’ve been feverishly moving objects for a gallery lighting project. 

That’s pretty much done now (and looking great) so now I’m feverishly moving the Dead Zoo’s collection of over a million insects out to a new home in the National Museum of Ireland’s Collections Resource Centre.

So this week I have an insect for you to identity, which should provide a bit of a colourful change from the usual vertebrate bones:

For some of you this may be way too easy, for others, way too hard. It help to know that this was collected in India and it’s around 25-30mm long.

I hope you have fun identifying it!