Thread subject: :: pinning alcohol preserved diptera

Posted by Louis Boumans on 31-12-2010 10:25

Dear Forum,

When pinning alcohol preserved material, eg from malaise traps, I notice that the wings often become wrinkled. Does it help if I transfer them to 30% EtOH or plain water first? I will experiment a bit, but maybe some of you have good advice?


Posted by Liekele Sijstermans on 31-12-2010 10:42

In Tachinid Times 7 (1994) page 3 - 4 O'Hara describes a method to prepare Tachinids from ethanol.


Posted by ChrisR on 31-12-2010 11:16

Jim's method with ethyl-acetate is probably the best of the 'quick and dirty' methods and would work well for tachinids. I haven't used it though because the specimens do come out very brittle and difficult to handle - hence the need to glue them to the pins. I think there is a more complex method used for smaller insects that involves using different dilutions of another chemical - I think John & Barbara Ismay use the more complex method because they tend to work on the smaller families.

If you can remove the specimens from alcohol within weeks of being caught then often you don't need to do anything more than drying them out. Some of the larger tachinids seem not to shrivel even when in alcohol for years :)

EDIT: For Louis' benefit the Tachinid Times article is here.

Edited by ChrisR on 31-12-2010 11:17

Posted by Steve Gaimari on 31-12-2010 19:34

Although a more dangerous chemical than ethyl acetate, hexamethyldisilizane (HMDS) is an excellent chemical for taking flies out of alcohol. Brian Brown published a note in Fly Times some years ago - found here. I also put up a web page about his protocol, telling how we apply it in our lab - found here.

Posted by Nosferatumyia on 31-12-2010 23:28

Severin and I use absolute ethanol - ethyl acetate processing of micropinned tephritoid specimens (micropin+pe foam piece), which is much safer considering absence of fume hoods at the Institute and home. Gentle gluing is obligate unless U want flies to fly away from micropins. Do not process DOUBLE-MOUNTED flies: macropin enamel surface and especially its head could be partly solved.

Posted by Louis Boumans on 01-01-2011 23:08

Thank you very much Chris, Liekele, Valey and Steve, your advice is extremely helpful!