Fairyfly - Collection and Preservation

Collection and Preservation

See also: Insect collecting

Despite their relative abundance, fairyflies are unpopular among modern insect collectors because of the great difficulty in collecting them. As one of the least known insect families, there is still a large amount of information that is waiting to be discovered about fairyflies. This is an area of entomology where an amateur naturalist can still make significant contributions.

In the 19th century, Curtis described the methods by which Haliday collected fairyflies as thus:

The minute Hymenoptera are best collected by beating into, and sweeping with, a net made of fine gauze, and Mr. Haliday recommends me to collect them in quills, and afterwards to empty their contents into hot water, by which means their wings are naturally expanded; then by introducing a card under them to take them out of the water, arranging the legs and wings when necessary with a camel's hair pencil, and leaving them upon the card till they are dry, they may afterwards be taken off with a penknife, and gummed upon the points of small pieces of drawing- or card-paper of a long triangular form. —John Curtis, British Entomology Vol. 7 (1830)

The best modern collection method is using Malaise traps. It requires little maintenance and can collect insects in great abundance. Other effective methods include yellow pan trapping, sweep nets, and suction trapping. Direct collection from leaf litter with Berlese funnels can also result in specimens that can not be collected by other means.

Rearing is also another method that can bring the most rewards. This can be done with wild host eggs or laboratory prepared host eggs that are exposed in suitable habitats outside. They can then be taken in after a sufficient amount of time has passed and examined for developing fairyflies. With this method, it is possible to observe the life history and determine the hosts of particular species of discovered fairyflies.

Preservation is a problem for fairyflies (and other small chalcid wasps). Their tiny sizes require special methods. Specimens have to be dried, if collected wet, e.g. if ethyl alcohol is used as the killing agent. Drying can make specimens extremely brittle, so additional care should also be taken not to disintegrate them. Mounting specimens (preferably in permanent slides) is also time-consuming and requires a fair amount of practice. They are gummed or glued into cards, as they can not be mounted on pins like larger insects.