General information

To make genitalia preparations, the abdomen of the specimen must be detached from the thorax. In fresh material, there is a greater chance of damage to tissue and genitalia than with dry specimens. Therefore, fresh material should be allowed to dry for at least one day at room temperature.

Equipment

equipment
chemicals and petri dishes
1. stereo microscope (magnification up to 100x)
2. small petri dishes
3. two pairs fine forceps, straight bladed
4. two (mounted) micro-pins, one of which has a terminal hook
5. two fine paint brushes, or a (mounted) snipe pin-feather
6. hypodermic syringe with extra fine hypodermic needle
7. 30% ethanol and 95% ethanol
8. 10% potassium hydroxide solution (KOH)
9. acetone
10. test tube

(for slide preparation)
11. glass microscope slides and (preferably round) coverslips
12. Euparal essence
13. Euparal mounting medium
14. chlorazol black stain solution

or

(when keeping genitalia in glycerine)
11. glycerine
12. small plastic genitalia vials

Removing the abdomen

lifting of abdomen
test tube with KOH and abdomen
Remove abdomen of pinned specimen by gently lifting it with the flat length of a pair of forceps (do not grip the abdomen).
Poor sufficient 10% KOH in a test tube to completely immerse the abdomen. Gently drop the abdomen in the test tube (e.g. from the corner of a piece of paper). Plug the test tube loosely with a tissue. Leave to macerate overnight.

Marking of dishes

Reserve one petri dish for 30% ethanol, one for 95% ethanol, one for acetone, one for Euparal essence and one for chlorazol black. Mark the dishes and pour the chemicals in just prior to starting the actual preparation.

Cleaning of abdomen and genitalia

Tip the abdomen from the test tube into a petri dish. Transfer to petri dish with 30% ethanol. Work under a low magnification setting of the microscope. Carefully remove loose intestines by gently flattening the abdomen with the fine paint brush. Lift the abdomen with the fine forceps by the anterior opening (opening at the thoracic end) and transfer it to a petri dish with acetone.
Gently brush off the scales, do not use force. Try to inflate the abdomen by inserting the needle of the syringe into the anterior opening while holding it with the brush, and squirt acetone around, thus ejecting dirt and residual KOH. Try to clean the abdomen as much as possible using the fine forceps. After this, the genitalia can be stained in chlorazol black.

Staining

The male genitalia are best stained before dissecting. Transfer the abdomen to the petri dish containing the stain solution and hold it below the surface for about 30 seconds. Transfer to a petri dish containing 30% ethanol. Use a syringe with 30% ethanol to jet-out excess stain (same method as mentioned above).