Instructions for Spreading Insect Wings
Entomologists depend heavily on patterns of wing venation to identify insects in the orders Odonata (dragonflies and damselflies) and Lepidoptera (butterflies and moths). The wings of these insects must be "spread" in order to ensure that the venation is visible.
The following steps will guide you through the process of mounting an insect so its wings will be spread.
- Pin the insect through the center of its thorax, leaving exactly 10 mm of the pin above the specimen.
- Adjust your spreading board so its central groove is just slightly wider than the body of the insect.
- Push the pin down into the spreading board's central groove until the wings are just even with the top surface.
- Prick one of the front wings lightly with an insect pin (just behind the strong vein on the wing's leading edge) and pull the wing forward until its hind margin is perpendicular to the insect's body. Use the pin to hold the wing in place temporarily.
- Using another insect pin, repeat step 4 with the other front wing.
- Using a third insect pin, prick one of the hind wings behind a strong vein. Move the wing forward until it just begins to slide under the hind margin of the front wing. Use the pin to hold the wing in place temporarily.
- Using a fourth pin, repeat step 6 with the other hind wing.
- Cut an index card into two narrow strips long enough to extend beyond the front and hind wings. Lay one of these strips over the wings on the left side and another over the wings on the right side. Secure the strips with more pins placed just beyond the wing margins.
- Once the paper strips are holding the wings in place, remove the four temporary pins from behind the wing veins.
- If necessary, use additional pins to hold the antennae in a natural position and provide support under a droopy abdomen.
- After allowing the insect to dry for several days, remove the extra pins and paper strips. Carefully pull the pinned insect out of the spreading board's groove. Handle with care -- your specimen will be very brittle.