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Curator of Diptera's blog

5 Posts tagged with the fungus_gnats tag

So Last week I performed a HUGE 9 minute set for a Museums show off. People from all over the museums and libraries sector come and present a skit on something about their work or their museum. Now I choose to highlight the wonderful creatures that are maggots. They are all over my desk, I get sent them in the post, yesterday I, alongside a colleague, were hunting for them in the wildlife garden, I was rearing them from poo in the towers – in fact, maggots are very dominating in my job. And quite rightly so.


So I thought that I would convert that into a blog about these fantastic things and why the collections and the staff at the Natural History Museum are so important with maggot research! I have briefly touched upon maggots before but i thought that I would go into some more detail.



Let’s first clarify what a maggot is. The term maggot is not really a technical term and if you type in ‘what is a maggot’ on Google you get this!


maggot definition.jpg


To this date I have never heard someone describe something they yearn for as a maggot but who can say what will happen tomorrow with language fashions.


The maggot is a juvenile or, as I prefer to call it, the immature stage of a fly. These vary in form across the order from the primitive groups of flies (Nematocerans) to the more advanced groups (Brachycerans). The primitive groups have a more defined form in having a distinct head capsule with chewing mouthparts and we refer to these as Culiciform (gnat shaped).


mossi larvae.jpg A mosquito larva which is culiform (gnat shaped).


Those more advanced flies whose larvae are without a head capsule and mouth parts that have just been reduced to hooks are called Vermiform (literally meaning worm shaped); and it is the later group that we generally call maggots!


blowfly maggots.jpgA slightly more informative picture of some Vermiform larvae - the maggots of a blowfly.


We can label describe these head capsules further into three types;

  • Eucephalic (distinct capsule and mandibles)
  • Hemicephalic (incomplete capsule and partly retractable mandibles)
  • Acephalic (no distinct capsule with mouthparts forming a cephalopharyngeal skeleton)


trichoceridae larvae c Matt Bertone.jpgA trichoceridae larvae (eucephalic) © Matt Bertone.



dipteraathericidae hemicephalic.jpgAn Atherceridae larvae (Hemicephalic).



And a housefly maggot (Acephalic larvae).



However for the purpose of this blog I will use the term maggots to include all Dipteran Larvae as there are some very important (and incredibly attractive) larvae from some of the more primitive groups. And they differ from most other insect larvae by the lack of jointed legs on their thorax. Beetles larvae are grubs, Butterflies and moths are caterpillars, bugs just have mini-versions of the adults, but they all have jointed limbs.


tipulidae drawings.jpgAbove are some of the more incredible images of a cranefly larva. But these are not the heads of the cranefly larvae but rather their anal or posterior spiracles (breathing tubes). Anytime I need cheering up I flick through images of posterior spiracles.


cranefly-larvae-resize-12feb14.jpgMost people just view the larvae from either above or parallel but these are from bottom on! (these above diagrams are from the brilliant book by Kenneth Smith on Identification of British Insects) but as you can see some of the more interesting features are from this angle.


These spiracles form part of a breathing system that enables the maggot to breathe whilst feeding. These vary across the fly group with there being 7 different set ups of the spiracles.

maggot-spiracles--resize-12feb14.jpgLocation of spiracles on the body of a maggot, shown with dots and circles.


The above diagram from top left to bottom middle shows (by dots and circles) where the spiracles are on the body. Some systems are very common such as the amphinuestic set up being found in most Diptera whilst others are very specialised such as the proneustic systems (only found in some fungus gnats). Some of them have taken their spiracle and run with it (as it were). Check out the rat-tailed maggot below (larvae of a hoverfly).


rat tailed maggot.jpg

Rat-tailed maggot (larvae of a hoverfly).


The mouth can concentrate on ingesting food solidly – just imagine 24/7 eating. Now the maggot stage is the one designed for eating. I often wonder what it would be like to have the lifestyle of a fly – born, eat, eat, eat, eat, eat, mate, die…..and therefore they don’t have to have all of the equipment of the adult.


As I have already mentioned the larvae of Diptera do not have legs as other groups do such as the moths or the ants. This is because they are highly specialised examples of precocious larvae i.e. examples of very early hatching. And this is what arguably has lead to the most diverse range of habitat exploitation of all insects. They are plastic; they can squeeze themselves into tiny holes and between surfaces and therefore take advantage of so many different food sources.


In the wonderful book by Harold Oldroyd – The Natural History of flies - there is a sentence that states that the larva and adult are more different from each other than many Orders of Insects. And so in many ways with many species you could argue that flies fit two lifetimes into one as they are often completely different, both in form but also in diet and habitat.


Maggoty enquiries


The Diptera team have been talking maggots a lot recently. One of us, Nigel Wyatt, is something of an expert already on most things maggoty, working on most commercial, consultancy and public queries relating to maggots.


I had one recently from a friend of mine. She is a vet and one of her colleagues works with Police Dogs. Her colleague was a little confused and concerned about a maggot that was defecated by one of the dogs as she had not seen one so large before. My friend immediately thought of me and sent it to the Museum in a little tube of alcohol. Despite the alcohol it was quite fragrant by the time it arrived on my desk but it was easily identifiable as a cranefly larvae. Now cranefly larvae are incredibly versatile in terms of their habitat – they live in moss, swamps, ponds, decaying wood, streams and soil but as I far as I know the inside of a dogs alimentary canal is not a known habitat. They consume algae, microflora, and living or decomposing plant matter, including wood and some are predatory but parasites they are not. This one had miraculously come through the entire digestive tract of a dog without being destroyed. No harm done except to ones nasal cavities.


However, cranefly larvae or leatherjackets as they are sometimes called have caused some problems to lawns due to them consuming grass roots. Wikipedia – the great font of scientific knowledge cites from Ward’s Cricket's Strangest Matches ‘In 1935, Lord's Cricket Ground in London was among venues affected by leatherjackets. Several thousand were collected by ground staff and burned, because they caused bald patches on the wicket and the pitch took unaccustomed spin for much of the season.’


Apart from the staff who help with identifications we are helping further with outreach by helping with development of a new, hotly awaited book on British Craneflies. Alan Stubbs (not the retired footballer but the rather more impressive Dipterist and all round Natural History Good Egg) and John Krammer (retired teacher and superb Cranefly specialist) have been working on this fantastic tome for a while now and we have all been trying and re-trying the keys to ensure that they work. Preparations of gentailia, wings and larvae have been undertaken at the Museum on both Museum specimens and ones donated by John, and images and drawings of these been done. Carim Nahaboo has been drafted in for some of the drawings so expect great things.


This is an adult Dolichopodidae but it is a fine example of Carim Nahaboo's artwork.


Flies and their offspring have a terrible reputation. People are disgusted by most of them. However, they are essential both for our health and habitat but also for telling us what is happening.


Dr Steve Brooks and his group at the Museum work on Chironomidae (non-biting midges), and more specifically the immature stages – their larvae. Chironomid larvae are quite primitive and as such have a complete head capsule which is … as the larval stages develop they shed their head capsules and grow new ones, and these discarded ones can be used to determine the environmental conditions of the habitat both now and in the past as well as monitoring heavy metals.


hgrimshawi-48125-1.JPG Head capsule of a chironomid, which can be used to determine past environmental conditions.


I first came to the Museum as a professional grown up thanks to Steve as I was conducting a study using Chironomids as indicators of environmental health as they are fantastic bioindicators. Many Chironomid species can tolerate very anoxic environments as they, unlike most insects, have a haemoglobin analog which is able to absorb a greater amount of oxygen from the surrounding water body. This often gives the larvae a deep red colour which is why they are often called blood worms. Although slightly fiddly as you have to dissolve the body in acid, the use of head capsules for identification (image above) is fairly straight forward. The little crown like structures that you can see are actually rows of teeth and these are very good diagnostic features. Steve has worked for a long time on the taxonomy of these species and his (and his groups) expertise has been used globally.

So as well as looking funky we can use them to tell us many things about the world of today and yesterday. More on maggots in the future.


This blog piece is written by the young and keen Victoria Burton, who rashly agreed to come away with the Museum's team of dipterists and the Dipterists Forum to Speyside in is her story.


Hello, I’m Victoria and I have just finished an MSc in Taxonomy and Biodiversity,  run here at the Natural History Museum, London.


I am also a fly fan, so when Erica mentioned there may be a space on the Museum’s collection trip to Scotland with the Dipterists Forum I had to tag along! As a born and bred Southron this was my first trip over the border and a great opportunity to see some of the habitats and species which are not found ‘down south’.


The trip started on a Saturday in September with an early meet up at the Museum to pack equipment into our hired people carrier or ‘van’ as it became affectionately known, before the long drive north. This was also a good opportunity to get to know the fellow dipterists I would be staying with for the next week and their dipteron predilections:

  • Duncan, our native interpreter/navigator.
  • ‘New boy’ Dan, fan of bristly flies.
  • Zoe, who spent a lot of time paddling for simuliids.
  • Vladimir, fungus gnat aficionado.
  • Not forgetting ‘The Boss’ Erica herself whom we rescued from the side of road after she was rudely dumped by an incompetent taxi driver!


After democratically deciding who would be sharing a room, copious wine and conversation were had before I retired, excited for my first visit into the wilds of Scotland. This began with being introduced to Dipterists Forum members and the customary discussion over maps.



Suggestions for a collective noun for dipterists?


We started with the Rothiemurchus Estate and on my first step into the Caledonian pine forest I was immediately struck by the wonderful scent of pine. The dipterists disappeared in all directions, and I began the sweep-stick head in net-poot ritual, although I had many escapes being distracted by the yummy bilberries (or blaeberries as they are known here) appearing in my net.


There were lots of the big hoverfly Sericomyia silentis, the first time I had seen live individuals; this impressive hoverfly became a familiar sight over the week, and always made a big fuss when caught in a net.


Sericomyia silentis having a wash and brush up on a leaf.


A long day of diptera in the field is inevitably followed by a long evening with diptera in the laboratory and so with a little bit of table rearrangement we soon had a makeshift lab in our cottage.



Must be the cosiest ‘lab’ I have ever worked in.


Our second day took us to Inshriach Forest, first stop Uath Lochans. These lochans, which our ‘native’ informed us meant ‘little lochs’ were breathtakingly still in the morning light, with a perfect reflection of the sky and mountains.



The beautiful Uath Lochans.


Around the lochans grew a colourful springy patchwork of heaths and other plants, mosses and lichens, dotted about with fungi including bright red Russula.


Bright red Russula fungi.


A handy boardwalk has been constructed around the boggy edges of the Lochans, from which I swept an amazing little fly. Running around in the pooter it looked like it was wearing boxing gloves and I was soon informed it was a shore fly (Ephydridae) called Ochthera.


Back in the lab I was encouraged to unhinge its raptorial forelegs, which inspire its common name, mantis fly. There is a lovely description in Colyer and Hammond’s Flies of the British Isles in their engaging style describing its “terrible fore-legs” with “tibiae curved and folded back upon the femora like the blade of a pocket knife, forming a trap from which the unhappy victim has little hope of escaping”.


Raptorial forelegs occur widely in insects, famously in the mantids, but also other groups of flies such as the hybotid dance flies which we found lots of during the week, and mantisflies, which confusingly are neither mantids nor flies but in the order Neuroptera.



The mantis fly Ochthera (probably O. mantis).

On day three we visited sites around Carrbridge, where I swept my first ever hippoboscid in Beananach Wood - these were Lipoptena cervi, the deer ked. They are very strange, flattened flies resembling lice, and must look even more louse-like when they settle down on a host and shed their wings; indeed Carl Linneaus originally classified them with headlice. Another peculiarity is that the females produce just one big larva at a time, nourishing it mammal-style inside their body, giving birth just when it is ready to pupate – aw.



Lipoptena cervi - I went a bit lepidopterist with this specimen, the wings are normally held over the abdomen, but you do get to see its bristly bum.


On Wednesday we headed to the seaside to visit Culbin Sands but unfortunately the weather was miserable (dreich in Scots-speak) so a midweek day off was announced.



Dan and Vladimir make a valiant effort to catch seaweed-inhabiting flies.

We met up with Duncan’s mum Sheena, aunty Moira, and friend for some tea and cake in Elgin before being brought to meet the Gordon clan and fed fresh homemade drop scones (Scotch pancakes) complete with homemade fruit preserves – heavenly!



Duncan's Aunty Moira and scones.

More deliciousness was to come when it was revealed that Duncan’s cousin Euan worked for BenRiach local distillery, so before long we were whisked off for a private tour and tasting session! Despite (or maybe because of) all the whiskey I managed my turn to cook dinner and all survived.



Euan presiding over the tasting session (whisky taxonomy?).



“And not a single fly was caught that day…” (Actually we did get a few!)


The fourth day of our trip arrived with better weather and surprisingly few sore heads, and we headed off to Insh Marshes which I was much looking forward to since I had heard great things about it, and I was certainly not disappointed. It was one of those sites that whisper “I’m special”.


On sorting my catch later I found my first ever pipunculid, or big-headed fly, which I like to describe as “massive head, all eyes”. Their heads are also notorious for falling off, so I was quite proud when I managed to micropin my specimen without casualty, only for this to be dashed when I later staged it.



Zoe and Erica sweeping their way along a valley in Insh Marshes.

Our last collecting day took us to some calcareous sites, and after nearly a week of acidic habitats it was quite a contrast to see some calcicole plants, many of which I am very familiar with, living as I do between two great ridges of chalk in Hampshire. Our first site was Fodderletter, a tiny but wonderful unimproved wetland SSSI huddled away on the Glen Livet Estate. Here we found lots of lovely big blowflies feeding on ragwort flowers, including the giant Cynomya mortuorum which caused much excitement, only slightly deadened by Alan Stubbs stating “oh yes it is quite common in Scotland”.



Handsome male Cynomya mortuorum with its lovely orange face and ‘mane’.


I was fortunate to catch a female on our next site, Creag Chalcaidh Quarry near Tomintoul. This was an intriguing site with springs spilling through the old quarry walls, producing chalky mats of algae. There were lots of unusual craneflies, which I don’t yet ‘do’ - their tendency for legs to fall off bothers my perfectionist nature, although this is soon to be addressed on a cranefly identification course.



Alan hunting rare craneflies in classic dipterist pose.


Our final site of the day, and indeed the trip was Bochel Wood, where I managed to catch an empid along with its meal, a bibionid. Since dipterists are, in my partner’s words “obsessed with genitalia” it would be remiss if I didn’t include a photograph of the impressive equipment possessed by this Rhamphomyia.



Crazy, crazy genitals…


On that note I’d better hand back to Erica, after raising a wee dram to great food, drink and company, and above all great flies!



A chilly Culbin Sands group shot.

With thanks to Daniel, Duncan, Erica, Vladimir, Zoe and the Dipterists Forum

Thanks also to Chris and the Angela Marmont Centre for use of the photo stacking system.


Hunting in Pembrokeshire

Posted by Erica McAlister Jun 21, 2010

Well I have just been to some of the most glorious countryside in the UK. The Dipterists forum annual summer collecting trip was based in Stackpole, South Wales at a Natural Trust Centre. This was surrounded by wood, and fields, and Lakes (containing Otters although I did not see any!!) and the Centre itself had a large hall within which we set up our microscopes!


One of the lovely lakes that had Otters.



It is always a great week, concentrating on collecting flies from as many different habitats as possible, to add data to recording schemes as well as building personal collections, and in our case building and maintaining the comprehensiveness of the National British Collection. We (another colleague and I) get to spend the week collecting, pinning and id’ing flies with some of the UK experts in a range of different fly groups. Alan Stubbs (co-author of British Soldierflies and their Allies, and British Hoverflies) is one of the main men (and very very good on craneflies) and an absolute ice-cream demon. Peter Chandler (co-author of ‘A Dipterist’s Handbook’ and the British Checklist of Diptera) is another and is the UK expert on fungus gnats (but not very good at opening ice cream tubs). They, and another 28 roamed the countryside for the best fly (and bee, sawfly, bug and the odd beetle! there were many groupies!!) John Kramer and Richard Underwood were also present who regularly volunteer at the NHM and again are very good Dipterists.


Please if you see these people do not approach (Dipterists at large)...



After a long drive, we had nothing to do but eat, a consistently good theme of the week. We were allocated rooms and then set up our microscopes. We had a quick walk down to the Lake which in the setting sun was more than pleasant


Hunting started properly the next day. We set off to the Coast to sample amongst the Dunes. I had great fun chasing Robberflies, trying to poot’ Dolichopodids of the cliff face, attempting to catch shore flies (they fly so close to the surface you just end up whacking the net against the rocks!) and sweeping along the edge of a stream whilst paddling!! Oh sometimes, fieldwork is just so difficult I don’t know how I cope...


Fieldwork involves a lot of ice cream....

Roger, Alan, Claudia and Stuart small.jpg


The afternoon we moved on to woodlands (now here you will be pleased to know that I scratched my legs to death) and ended up at Scrubby Bottom where we were attacked by horseflies (which we killed and have subsequently pinned ).


scrubby bottoms.jpg



The evenings are spent eating, and pinning. We use Cherry Lorrel for killing the flies as it is not only an effective killer but it also relaxes the specimens as well and so we are able to pin them in the most appropriate way. You can stick a micropin through most of them and then pull out their legs, so that most of their limbs are elongated and the wings are carefully pinned, spread away from the body.


Here is a horse fly which has had it's wings spread out so we can clearly see the markings on the abdomen



These are left in that position overnight to ensure that the legs, wings etc set in the correct position. We had prepared some little labels which enabled us to quickly sort the material into correct dates and sites.


The next couple of days were doing very similar things. We would gather around in the morning, pouring over maps. They had been highlighted with ‘hotspot’ areas of woodlands, marshes, dunes etc which were thought to be great for the little flies. Most people were collecting specific families of flies and therefore their requirements would differ. Peter was collecting fungus gnats and therefore preferred damp woodland, whilst I was hunting for Robber flies and so liked hanging out in the dunes. That must have been a lovely sight for the general public to see me on my hands and knees with my pooter tube in my mouth and a net in one hand poised, ready to catch a fly. There may have been a little bit of bad language as well when I missed them….


Me collecting from a stream (thanks to Ken Merrifield)




We took one day off to collect on Skomer. I say take off as although I and the others did collect flies, I got very distracted by the Puffins . Amazing little things. The path ran alongside the cliff and as they land with their beaks stuffed full of fish, they wait for us humans to move aside so they can run over it and into their burrows. We had accidentally left a bag in the way and you could almost sense the impatience (and watch them tap their little feet in frustration) as they waited for us to sort ourselves out and move the offending article before shooting across!!


here it was waiting.....

puffin 2.jpg


And then a mad dash across the path


puffin dash.jpg


One of the most productive days was just down a country lane where there was a mixture of open habitat and closed canopy (and therefore a slightly damper area). Loads of lovely flies here including Horseflies (which I have to say are incredibly attractive J), Hoverflies and some Mycetophilidae (fungus gnats!)


As well as us Dipterists, we had some other entomologists sneak along with us including a sawfly specialist and a bee specialist. It is actually really nice to have a variety of people as you end up learning other interesting facts and how to collect different groups.


All in all a brilliant week. I have to say that is some of the loveliest countryside I have seen in a while. I can not believe that I have been all over recently and I seem to be raving more about what is on our own doorstep!


Excellent meadows for the hoverflies etc



Am back in the Museum for a week as it is National Insect week and I am doing two talks!! It should be good as I just talk about how wonderful flies are!!! (


Fieldwork in Shropshire

Posted by Erica McAlister Oct 16, 2009

Ok, so before my main post I just want to add a little side note that if anyone missed the new 'David' documentary (I was on fieldwork), that after about 24 minutes in there is the most fantastic piece of film showing stalk-eyed flies inflating their stalks. the flies


But back to fieldwork. With a car packed with microscopes, field guides, pinning equipment and exciting new camera lens we (Kim and I) set off for Bridgnorth, Shropshire. And what a lovely place it was! We arrived early and as the others were not due till 7.30 we went for a walk to and around the town. I have a new macro lens for my camera to enable me to take loads of insect pictures but I need a little more practice; it does not help when the insect is moving, the leaf that it is on is moving and me too! We collected comments from the passers by, with one even saying I reminded him of his son....It is a lovely town though, on two levels connected by the oldest and steepest inland funicular railway - one whole pound for a return journey!


We met Roger Morris, who organises the fieldmeetings of the Dipterists forum back in the B&B and then the rest of the motley crew back in town. Found a restaurant that made the best pies . Food and nutty ale are very important components of fieldwork. The others were Alan 'Mr Whippy' Stubbs, Peter 'Gnatman' Chandler, Chris 'Spiderman' Spiling.  (A photo below of gnat man in action!). We were joined during the course of the trip by Hannah 'happily married' Cornish and Malcom 'extender net' Smart - a Robber fly expertpeter bum.jpg

I think that just after this photo was taken was my first field injury of the trip. I too had my head in a net sucking up flies into my pooter when I realised that I had not just swept up flies but also a wasp...and she was a bit angry. I was stung three times (I still have the lumps) on my head and she got stuck in my hair! But I calmly took my hair out of its ponytail and tried to ensure that she had finally got away. I asked Alan to check as he was the closest. Upon telling him that I was attacked and that I needed him to check for the wasp his reaction was - 'it's gone' and then he walked off!! I could have been dying!! I fell down a whole that resulted in one leg and foot become oxidised .


The practice of the meetings is to conviene at one of the B&Bs that we are staying at, check the maps, and then head off in convoy for some net action. We travelled around three counties hunting for flies on this trip and I have to say that I was very impressed. The mornings were cold and so we got to relax and try and identify material from the previous days - the flies would not be out in the cold . We averaged three sites a day. We were specifically trying to find fungus gnats, craneflies and platypezids. I did not get any of the latter . Afterwards we would go back and pin for a couple of hours before dinner and then for a few more after dinner. We came home with a lot of material that we can add to the synoptic collection for the AMC (Angela Marmont Centre). There were relatively few gnats though as there was very little fungi. The area has not had much rain at all and everywhere was very dry. We were hoping for over a hundred but not sure that we got 50 (species not individuals). But as the fauna was so deporporate we actually managed to identify a fair chunk of the material and we have got many different hoverflies, gnats, craneflies, muscids etc etc.



Here's one of the pretty hoverflies.


We were also shown the larval habitats of hoverflies with Roger carrying out some excavation work on plant roots (they were all put back afterwards...well apart from one....but enough said).


syrphid larva.jpg

All in all, very successful. It was good to get back into the field and see different parts of the UK. I need to work on my macrophotography but sitting in front of me at work are boxes of material that will keep me going for a while!


Pinning flies

Posted by Erica McAlister Aug 4, 2009
We undertook some fieldwork on Bookham Common a while back, which was being filmed by the BBC.  We set up some pitfall traps, a malaise trap (a tent!) and then undertook some canopy sampling. I have finally had a bit of time today to start sorting through these specimens. The beetles have been studied from many years on the common and so it is nice to look at the fly population. There are lots of fungus gnats, Dolichopodids, hoverflies, houseflies, and some robber flies (which are very cool). I have only just started on the pinning of the specimens from the malaise trap and there are several hundred to do!! Once pinned, I will sort to family level and pass them on to the appropriate people to identify if not within my area.  It’s good to be able to look at specimens as most of the day I have been answering emails and constructing lists. Tomorrow I will be spending the entire day making labels to put in our new Synoptic collection.

I have just recieved an internal grant to have someone recurate and incorporate a collection of fungus gnats from Russia into our collection. This was a research collection and all the names are in Russian, some on dodgy pins, there is dried up genitalia everywhere (a common problem!!) and no label saying that the material is ours. Our new assistant has her work cut out!

Erica McAlister

Erica McAlister

Member since: Sep 3, 2009

I'm Erica McAlister, Curator of Diptera in the Entomology Department. My role involves working in the collection (I have about 30000 species to look after and over a million specimens), sometimes in the lab, and thankfully sometimes in the field.

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