Thread subject: Diptera.info :: Suprasquamal ridge

Posted by thomas@HK on 30-04-2005 16:14
#1

hairs on suprasquamal ridge are critical feature in identification. i have seen some specimens which wings were fixed in a posture that suprasquamal ridge can be examined easiy. how can it be done? does it need some dissection?

Posted by Paul Beuk on 30-04-2005 16:25
#2

You should let dried specimens soften in a humid environment and when the wings can move, just use some plastic or something soft (plastozode) where you can place the pin. Using several other pins or objects that will suite your needs, you can then position the wing such that you can see the ridge.
The time needed for softening the specimen varies by the size of the specimen, the ambient temperature and sometimes how long the specimen has been dry. A simple softening chamber can already be made from a saucer with some rather filter paper or cottonwool and an upturned glass. Make sure that the specimens do not stay in too long, to prevent moulding or water-logging, and make sure they are dried rather quickly after you finished positioning the wing(s), again to prevent moulding in warm, humid environments (as maybe you have in HK).