A huge thank-you to everyone who has been helping us transcribe the Parasitoid Wasp “Killer Within”  specimen labels, in the ‘Miniature Lives Magnified’ section – they can sometimes be quite tricky, but you are doing work that will aid many future discoveries. This first set of slides is now 84% complete, and it would be awesome to finish those before the end of the year, if anyone is up for a final push!

But in the meantime, we’d like to share some exciting research with you, that Dr Gavin Broad, Principal Curator of Hymenoptera at the Natural History Museum has just co-authored. Together with his collaborator Dr Simon van Noort, Curator of Entomology at Iziko South African Museum, they have identified three new species of parasitoid wasps  – two of which were laying undescribed in our own collections!!

All three species belong to the genus Genaemirum, which is found across Kenya, Tanzania, Uganda and South Africa. The finds bring the total number of species in the genus to eight – and offer more clues to the genus’ biology, which is poorly understood.

Deadly dinner guests

Parasitoid wasps lay their eggs in or on a host animal, eventually killing it when the larvae hatch and eat their host. This lifestyle has seen some parasitoid wasp species used as pest control, particularly if the hosts cause destruction to economically important crops.

Their fatal effect on the host also distinguishes parasitoids from parasites, which live off a host but don’t usually kill them.

‘Until now, we knew almost nothing about the biology of Genaemirum species,’ says Dr Gavin Broad, Principal Curator of Hymenoptera at the Museum, and a co-author of the research. ‘They were first described in 1936, but since then we’ve only been able to guess at the hosts that they parasitise.’

However, one of these three new species, G. phagocossorum, was reared from a log infested by the cossid moth Coryphodema tristis.

‘This suggests that members of the Genaemirum genus live on wood-boring moths – something that was suggested, but never confirmed, as long ago as 1967,’ says Dr Broad.

‘It’s exciting to think that these specimens could finally help us answer that 80-year-old question.’

Warthog wasp

It’s not just the mystery of its host species that has made Genaemirum an interesting genus to study.

‘They have the most extraordinary head structures,’ says Dr Broad. ‘Gerd Heinrich, who originally described the genus, characterised them as “monstrous”.

‘In fact, one of the species we found in the Museum’s collections has the most extreme head I’ve ever seen.

‘It has massively expanded genae, or “cheeks”, a long lower face and horns above the antennae. We named it G. phacochoerus, after the genus name for the warthog, because of its striking appearance.’

Still digging

This unusual head shape lends weight to the suggestion that the genus parasitises wood borers, according to Dr Broad.

‘It looks like the female’s head has developed into a shovel shape,’ he explains. ‘This could help her shovel her way through piles of frass – the waste produced by the moth larvae as they bore through the wood – to get to a host for her eggs.’

The hunt for answers isn’t finished yet, however. The research, a collaboration with Dr Simon van Noort, Curator of Entomology at Iziko South African Museum, is part of ongoing efforts to document African parasitoid wasps in the family Ichneumonidae.

‘If we had a male G. phacochoerus specimen to compare to the female, that would tell us even more,’ says Dr Broad. ‘The shape of its head could support or refute the wood-borer host theory, since males don’t need to access a host.’

‘But for now, we’re one step closer to understanding these strange species.’

Read the full news story on the Natural History Museum website: http://www.nhm.ac.uk/our-science/science-news/2016/december/monstrous-wasps-could-reveal-their-species-secrets.html

Welcome to Miniature Lives Magnified!

Here at the Natural History Museum, London, we are so excited to bring you a brand new expedition group focusing on the transcription of microscope slides.

We have taken images of 100,000 microscope slides of a variety of insects, many of which are invisible to the naked eye.  We’ll be releasing the images of these insects in small batches.

Our first expedition is called ‘The Killer Within: Wasps but not as you know them’ and focuses on a group of tiny wasps called Chalcids, pronounced ‘kal-cids’.  Just millimetres in length these wasps are parasitoids; they lay their eggs inside other insects and the emerging larvae eat their host inside out, growing and pupating until they are mature enough to burst out as adults.  

But the gruesome killing habits of Chalcids have an advantageous role in our food production systems.  Many of the host species of Chalcids are plant pests that have devastating impacts on agricultural and so Chalcids are used commercially as a biological control agent.

Perilampus aeneus

Being sooooo tiny Chalcids are really hard to study, which means there are huge gaps in our knowledge about their ecology and behaviour.  We want to start unlocking some of that knowledge from our collections, which is why we have brought the slides to you the Notes from Nature community.

To get stuck into our first batch of microscope slides visit the ‘Magnified’ group, indicated by the microscope icon.

And do let us know what you think of the project in the ‘Magnified Help’ talk group.

We hope you enjoy the slides and we’ll see you in Talk.

Best wishes from Jade and the Natural History Museum team.