Dissection and slide-making techniques
It is often necessary to examine the male or female genitalia when identifying tortricid adults. The following is an
guide for dissecting males and females and preparing slides for examination of genitalia under a compound microscope.
Instructions for removing specimens from sticky traps are also provided.
Materials
The following materials are needed for most procedures outlined on this page. If you are planning to slide mount the genitalia,
you will need standard microscope slides, cover slips, and mounting medium. Euparal mounting medium sold by Bioquip Products is recommended.
| Brushes (two, synthetic, No. 0, 00) |
Soapy water solution |
| Forceps (two pair, Dumont #5) |
Genitalia vials |
| Syracuse watch glasses |
Glycerin |
| Petri dishes (glass) |
Ethanol (95% or 100%) |
| Potassium hydroxide (KOH, 10%, or pellets) |
Stains (optional) |
| Histoclear (citrus oil) |
Dry bath heat block (optional) |
| Dissecting microscope |
Slide making materials (optional) |
To start
- Create temporary labels to track the abdomen/genitalia throughout the process. Place on label on the specimen and keep the other label with the abdomen/genitalia
as it moves through each step.
- If removing the specimen from a sticky trap, cut a piece of the trap containing the specimen and immerse it in citrus oil until the specimen floats free. Alternatively,
the abdomen can be removed from the specimen while it remains on the sticky trap. Abdomens should be soaked in citrus oil as the "sticky" (PIB) will interfere with the
dissection process.
- Place the abdomen (free of PIB) in a solution of 10% KOH. If a dry bath is available, let the abdomen sit for 45 minutes-2 hours at 50° celcius. If a dry bath
is not available, let the abdomen sit overnight (12-24 hours) at room temperature. The abdomen should be checked periodically; it is ready when it is completely pliable
and scales are easily removed. Do not let the abdomen sit in KOH for too long or it may be easily damaged during dissection.
- When the abdomen is ready, remove it from the KOH and place it in a Syracuse watch glass full of water. It is often helpful to use a drop of soapy water in the dish
to break the surface tension. Continue on to the illustrated dissection techniques below for male or female genitalia:
Illustrated dissection techniques
References
(The following references are in PDF format and open in a new window):
Quick dissection guide - Passoa & Gilligan.
Clarke, J. F. G. 1941. The preparation of slides of the genitalia of Lepidoptera. Bulletin of the Brooklyn Entomological Society, 36:149-161.
Miller, R. S., S. Passoa, R. D. Waltz & V. Mastro. 1993. Insect removal from stick traps using a citrus oil solvent. Entomological News. 104(4): 209-213.
Robinson, G. S. 1976. The preparation of slides of Lepidoptera genitalia with special reference to the Microlepidoptera. Entomologist's Gazette. 27:127-132.
Winter, W. D. 2000. Basic techniques for observing and studying moths and butterflies. Memoirs of the Lepidopterists' Society, No. 5:1-444.
Equipment suppliers
(The following links require an Internet connection and open in a new window):
www.bioquip.com (slide making materials, forceps, vials, chemicals)
www.carolinabiological.com (slide making materials, chemicals, glassware, stains)
www.finescience.com (forceps and microdissection tools)
National Diagnostics (Histoclear)
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