Paul Beuk wrote:
Both could give the necessary details, check the pictures in the linked publication. I personally probably would do simple preparations to confirm species (so not resulting in those well stuctured images). Abdomen (or just the tip if it is a male) in lactic acid, few seconds in micro wave (twice, a minute or so apart), and then transfer to alcohol (if it may swell) or glycerine (should not swell that much).
Others will prefer other methods...