Scotty Dodd invited us to participate in this new venture by Surrey Wildlife Trust, aimed at getting more people interested in insects, particularly in the hope of eventually bringing new recorders to the county. A party of ten ENHS members filled the little workshop, held at SWT's Pirbright headquarters, every attendee being provided with a microscope.
A general introduction to insects was given by Scotty and his colleague Simon, an expert on ground beetles. Nicola, an ant specialist, was also on hand. We were told that insects are mostly pretty robust and easy to handle, but unfortunately if the identification of a specimen requires the use of a microscope, the insect may need to be killed. Identification is problematic in many large groups of insects. There are many good general books available to aid identification, but they are often of very limited use for serious recording purposes. Websites are now a useful source of detailed information, and a means of sharing news of finds.
We were given an introduction to the parts of an insect: head, thorax and abdomen. The thorax has three segments, each with a pair of legs, the last two with pairs of wings. The wings are the insect's special feature, as they are not modifications of another limb. Insects are divided into two groups: the exopterygota, which develop through several similar stages to adulthood, and the endopterygota, which have distinctly different stages (e.g. caterpillar and butterfly).
There followed a display of various orders of insect, including hymenoptera, where the difference between bees and wasps was demonstrated and we were introduced to their cousins the sawflies, ants and ichneumons. The true flies are two-winged insects, with additional `halteres' replacing the rear wings. These are organs of balance which give the flies their exceptional manoeuvrability. A fly's mouth parts are a tube made up of a combination of smaller parts, through which they suck their nutrients. Time did not allow a full run-through of every group, but we also saw the structure of beetles, dragonflies, butterflies and moths, before an interval for tea.
The second section of the workshop was the practical session, in which we selected items from the excellent collection made available. With the aid of keys we attempted to identify our specimens to insect order, and generally we succeeded rather well, even with some of the more obscure ones. The evening ended with another plea from our tutors to get involved with insects in Surrey, to help fill the gaps. There are too few people recording the less popular groups, even though some, such as the orthoptera (grasshoppers and crickets), are attractive, available, and not too difficult to identify. Any takers?
Dick Alder