My thanks go to Ken Crick who has kindly written and supplied the content of this page.

In his narrative Ken refers to the field guides written by Steve Cham. These are available on line from Amazon priced at £7.50 each.

A Foreward by Ken Crick

An Introduction

Most observers of dragonflies and damselflies restrict themselves to the final life period of the insect, which is when they are on the wing. This is understandable as this is when they are visually most appealing and obviously active. However, for most species breeding in the United Kingdom, a greater part of their life is spent under water.

The study of larvae allows the keen observer to extend the dragonfly and damselfly study season. Netting during the winter produces a poor return; larvae are most easily found from the beginning of March and most easily identified as they approach their final aquatic life phase. Up until the end of November netting can also be profitable as many early season dragonflies and damselflies have by this time, achieved significant size which allows for positive identification.

The study of larvae equips one with the skills to readily identify exuvia, the shed larval skin, often to be seen amongst emergent water side vegetation. Records of exuviae, their location, species and numbers are most eagerly sought by wild life recording bodies as they provide objective evidence of dragonflies and damselflies living out their full life cycle at the declared location.

The Equipment

The collection of exuviae requires little by way of equipment, only a few plastic tubes with blank labels on them, to write on the location and date, to negate the risk of forgetting what was recovered from where. Netting requires a little more investment in equipment.

Some practitioners wash the netted sample several times passing the sample between two white buckets removing detritus and as much silt as possible before placing the washed sample in a shallow white tray. The net, buckets and tray can be obtained from suppliers of ecological equipment, I get my buckets for free, from the local pub, they contain the oil used for cooking and are only thrown out when empty. The pub buckets come with a lid which can prove very useful. For a white shallow tray, those used for emulsion paint applied with a roller will do very nicely when empty and washed clean.

Another technique is to lay out a sheet of pale coloured plastic by the bank and just empty your netted sample complete with detritus onto it, now watch over it for a couple of minutes to see what crawls out, placing any dragonfly larvae in the shallow white tray, which of cause contains clean water. Other practitioners dispense with every thing except the net placing one hand under the netted sample and looking directly into the net to see what if anything can be seen climbing to the surface.

Dragonflies (Anisoptera)

As with the Damselflies, we start with an image of the dorsal (upper surface) view of the various members of the dragonfly families found in Southern England, south of the M4 Reading to Newbury corridor.

002 General shapes Large e-mail view

  Figure 8

Addressing the lower line first it can be seen that the first three images going from left to right have very individual shapes.

The Golden Ringed Dragonfly (C. boltonii) is powerfully built. The labial palps viewed from the front are diagnostic, see main menu – Larvae – Golden Ringed Dragonfly.

The Hairy Dragonfly (Brachytron pratense) has a relatively long almost parallel sided abdomen but the small eyes and angular taper to the head are characteristic. For detailed key features click to main menu – Larvae – Hairy Dragonfly.

The Club Tailed Dragonfly (Gomphus vulgatissimus) is unique with 4 antennal segments and a heart shaped head, for detailed images click to main menu – Larvae – Club Tailed Dragonfly.

The Emperor Dragonfly (Anax imperator) is the largest final instar larva in the UK. The head when viewed from above is distinctive; the rear margins of the eyes are all but parallel to the rear of the head, see main menu – Larvae – Emperor Dragonfly.

The Hawkers will be viewed together: There overall outline viewed dorsally is similar. Migrant hawker is considerably smaller in the final instar phase than the other three, see main menu – Larvae – Migrant Hawker for key Features and figures 9 & 10 for direct comparisons.

078 Haw labium  comp all 4 copy copy

Figure 9

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