[Syrphidae] Sodium benzoate vs ethylene glycol?

[Chris Bergh]

Hello. I've had a couple of different people mention a couple of different
approaches to preserving adult syrphids captured in water pan and emergence
traps. Sodium benzoate is mentioned in a few papers and someone here told
me that they used ethylene glycol. Flies will be collected from the traps
at intervals no longer than 7 days. Any feedback on the merits of one or
the other would be greatly appreciated. It is likely that the samples will
be stored in vials in alcohol for a number of months before ID, so that is
also a consideration. Thanks very much. - Chris
J. Christopher Bergh
Virginia Tech
Alson H. Smith, Jr. AREC
595 Laurel Grove Road
Winchester, VA 22602
Tel: (540) 869-2560 ext. 32
Fax: (540) 869-0862