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There doesn't seem to be common to keep a fly collection in alcohol. Is there someone who does this and can tell us a bit about the equipment and best practices? I wonder what container is used for this. The reason I ask is I got a few nice small plastic micro tubes (2ml) from a collector to send beetles by mail (but not in alcohol). Not sure what it is named in english (in swedish mikror?r/kryor?r). I suspect that insects kept in alcohol is stored in small glass tubes and not plastic ones!?

I'm also interested in how storing other insects in alcohol is done.

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it is enough to use ethanol 70%. Plastic vials are ok. I never had any problems to keep up flies inside plastic vials! Alas, the glass can broken... I would advice plastic vials tight and using ethanol 70%. If you want to send the fly for DNA analysis use ethanol 95% (or 90%). NEVER use formaldehyde because it alters the structures of the specimens.

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I can share with you my negative experience
After Paul and Kahis advises in:
http://www.diptera.info/forum/viewthread.php?forum_id=21&thread_id=6523
I did try to collect in alcohol and pin afterwards.
My test:
1. Pinning from alcohol requires much more job and time than pinning of fresh flies.
2. Pinning fresh flies in sito permits to get much better order: legs, genitalia and whatever we need to examen on this fly.

I go on pinning fly the same day I collect its!
Nikita

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hi crex,

i think for that small plastic vials the name is Eppedorf tube (at least in romanian... a direct translation... where is the case).

my oppinion is that this are very good for keeping. but one advice... not keep beetle or anything else without alcohol for to much time. otherwise there will develop a lor of mold (i'm telling this from my experience).

just collect and trow the fly/beetle/other insect (except butterflies) inside.

hope this helps you,
cosmln

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I do the same, Nikita!

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I would echo Nikita's comments. Pinning from fresh-caught and freshly killed specimens is always the most preferable way, in my opinion. Collecting into alcohol is only done when it is absolutely necessary: 1. where the specimen was trapped into alcohol (eg. Malaise or Pan Trap); 2. a specimen is being sent in the post by someone who doesn't have pins etc; 3. or other 'exceptional circumstances'.

Under #3 I list my trip to French Guyana where I decided to catch mainly large bees & wasps and the best way to kill them was to drop them into alcohol - but even then I still got stung once! We were moving around the country too much to allow me to pin specimens each evening and the humidity out there would have prevented them drying anyway. So, alcohol was a good killing agent and it helped preserve & protect the specimens and store them in a relatively small space. But most of the resulting specimens were very hard to set because they had contracted all their muscles. Luckily for me I didn't mind that too much and I side-pinned almost everything anyway.

Chris R.

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Hehe, I never said that you should collect in alcohol and pin them afterwards. I keep them in alcohol.

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Thanks for the response. I meant really to store the insects in alcohol, not just temporarily keep them during trips etc. I see now that no one seems to do that, i.e. keep (store) his/hers collection entirely in alcohol without pinning the specimens.

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Good tip on Eppendorf tubes ... didn't see Pauls post. Perhaps he could expound on his views if he keeps his collection in alcohol!?

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eppendorf tubes are too small... I never saw eppendorf tubes bigger than 4 cm? I don?t recall well, but they usually are pretty small. But they are very tight what is good.

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I do store all my specimens in alcohol now.
In 1.5ml Eppendorf tubes the smaller ones and in bigger tubes the rest.
Take care with the caps, they does not fit perfectly sometimes, and the alcohol evaporates. The tubes can be put in hermetic jars filled with alcohol.
Even it is good that you have sufficient room in your freezer for your jars.

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Why do you keep the collection in the freezer?

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I keep most of my specimens in alcohol, partly because of the number - it would take too much time and space to pin or card-mount them all. And partly because dry specimens tend to go mouldy eventually in this part of the world. Entomologists here who keep their houses much warmer than I do still have problems with mould, mites and Psocoptera.

I find there is no problem with extracting the genitalia from alcohol- stored specimens. In fact it is often easier than from the fresh specimen. The problems are that colours are often very different when the fly is in alcohol, and if the bodies have leaked grease into the alcohol, the specimen will be thinly coated with it even after you have dried it out. That makes it hard to see dusting.

I use 70% industrial meths and 30% water, and it is best to use distilled water, especially if you are in a calcareous district, because calcium compounds tend to precipitate out. It doesn't have to be perfectly distilled water. I use the contents of a dehumidifier.

One drawback is when you want to compare your catch with reference specimens. It is time-consuming picking them all out of their tubes, and because each specimen doesn't have a label attached like it would if it was pinned, you need to work out a system for remembering which came out of which tube.

John Bratton

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As a summary (or my opinion that is):

Pros:
* Pinnging: Ease of use - good for reference collections, if you live in a climate where a dry collection is easy to keep.
* Alcohol: good for mass storage of large samples, and for soft insects (most nematocera).

Cons:
* Pinning is slow. Soft insects will not keep their shape. Pinned specimens are easily damaged by careless handling or pests - also mold in some climates.
* Wet specimens are difficult to compare with dry flies. Some details can be difficult to see. Colour will change with time. Collection needs regular maintainance.

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I don't think I'll be able to keep a pinned collection, so small alcohol tubes could be an alternative for a tiny collection. Do all use Eppendorf tubes as containers? The few tiny tubes I've got are not pointed in lower end of the tube. I also have seen in lab equipment shops that there are nice little boxes to store these tubes. How about plastic vs glass? The ones that I think is glass seems to be transperent which maybe means that you wouldn't even need to take it out of the tube to study the bugs ... but if you keep many bugs in each tube then that probably would not be as good.

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I use tubes with screw caps and a rubber lining in the cap. For long-term storage it is advisable to keep these separate tubes in a larger jar with alcohol or do an annual check to see if alcohol levels are acceptable. The rubber lining may start to decay, so the caps should be checked as well to see if the need to be replaced.
Alternatively, you can use glass vials with cotton wool to close them and keep those in a larger jar with alcohol. Disadvantage of cotton wool may be that smaller flies get stuck in the cotton wool.
In general, I'd prefer glass over plastic even though glass, on average, will be more expensive. Plastic may degrade over time (burst) and glass may give enough visibility to examine specimens without having to take them out. Problems with the number of specimens only arise when there are really many of them in relation to tube size and when too much alcohol is in the tube. I store one species per tube, unless the specimens will not be identified (for example, all Sciaridae will go into one tube, all Cecidomyiidae, all Chloropidae, all Calyptrates, etc.).

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Thanks Paul. Do you use 2ml tubes or even smaller ones?

If anyone got photos to show the vials or Eppendorf tubes and the way you store them it would be interesting to see. I found these nice 2ml Larvengl?ser with boxes to store it.

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I have 5 ml tubes (50*13 mm).

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Ohh, large ones. Any hints on the systems for labeling the collection. Inside the tubes, sticker on outside of tubes or just some number on the lid and notes on the side?

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Inside ONLY vegetal paper and written by a pencil. Outside I put vegetal paper and use a transparent gum tape, so label cannot be lost. (really, I use two, one for the stopper, and another one, on the vial.)
I put in that label, species name, date, location, and sometimes male/female symbols. I put a code as well.