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This is how I spread moths and other flying insects that are too small for a conventional spreading board. The moth was captured by sweeping it into a glassine envelope, which was promptly folded to prevent damage to the wings from fluttering. The envelope was then placed in ethyl acetate vapor to kill the moth. The envelope was then opened to air to desiccate in a cloth-covered Mason jar before being put into pest-proof storage. The moth was rehydrated in a relaxing chamber for 24 hours before spreading. It was placed on its back in the center of a small Plastazote Foam disk under a low-power binocular dissection microscope for this. Its position was stabilized with a 0.15 mm diameter Minuten Pin pushed vertically through the thorax, plus more pins that only penetrate the foam on either side of the abdomen (to keep it from rotating). The latter may suffice to spread some specimens, and the pin through the thorax may not be needed.

If a moth is to be permanently pinned with a full sized insect pin (assuming it is large enough to do so), the pin head may be pressed into the foam through a pre-punched hole to put the moth on its back. Pins that are to be left in place in the foam are best manipulated with flat & rounded tip Swiss style #2a stainless steel forceps. If the pin is only used to move body parts (not left in place), greater control is afforded by holding it in a pin vise, with the tip bent at an angle.

Once secured to the foam, Minuten pins are used to spread the wings and position body parts. For this, the wings are first flattening against the foam surface with a highly oblique pin (almost horizontal) pushed into the foam. A pin so placed often provides enough friction so that the wing can be pulled forward to the correct position as shown. The pin must be long enough to extend beyond the wing when this is done. If the moth is too small to use forceps on the wings (which may tear), one may be able to use a minuten pin to sweep the wing forward without penetrating it. This is a delicate procedure, though. It is sometimes necessary to puncture the wing behind a major vein to drag it forward and pin it to the foam temporarily for correct placement. This is more likely to be necessary for rehydrated moths; fresh killed is always better. To secure each wing in place, a pin is then pressed into the foam vertically near the tip of the oblique pin. A third pin was then used to push the oblique pin down the side of the vertical pin until the wing is pressed against the foam. The wing is held there by inserting the third pin into the foam. Any pin needed to temporarily hold the wing in place is then removed. One can make sure the wings dry flat (they tend to curl) by securing it with other such pin triplets at a number of locations. Legs and antennae are also positioned with pins, as shown, so that key features are easier to see. Carefully remove the Minuten pin through the thorax once the moth is spread, while using another pin in a pin vise to hole the moth down.

It is best to use slightly magnetized forceps to remove the pins after the specimen dries. The one linked above comes this way. This allows the pins to be removed from the foam without a potentially damaging lateral flick when the pin is pulled from the foam. The foam is translucent enough to see the pin point just under the surface before this happens. At that point, open the forceps and finish removing the pin with the pin magnetically attached to the forceps. Ideally, the magnetic pull strength should be only a bit more than needed lift the pin itself.

The moth may be point-mounted if it does not have a permanent pin in place already after all the pins are removed. I general use a 3 mil (80 µm) diameter tungsten wire with a bend as close to the tip as possible for this. One may bend and cut the wire while it is under tension simultaneously with diagonal cutters for this. Tungsten is best because it is the stiffest metal. Insect repair adhesive bonds the wire to the moth. The tip is bent so that the adhesive drop stays near the tip. That is, the adhesive is drawn to the inside of the bend by surface tension. The other end of the wire is sandwiched between two small squares of self-fusing silicone tape pressed firmly together with narrow-jawed vise grips. This allows the finished product to be pinned to a foam surface with a full-sized insect pin pressed through the tape.

I selected a relatively large specimen so that the pins are not too crowded to better illustrate this technique. Here are examples of much smaller specimens (in increasing order of size) prepared this way:

For small clear-winged insects which have been stored in fluid preservative, it is often best to spread the wings with the foam disk and specimen under water to prevent the wet wings from wadding up due to surface tension.

This image is from a Helicon Focus processed stack of 71 images with a 181 µm step taken with a Nikon 200mm F/4 AF-D ED-IF Micro Nikkor macro set to F/4 + Nikon D810 camera.