Worcestershire Record No. 5 Nov 1998 p. 12

DRAGONFLY ROUNDUP - 1998

This year was rather disappointing for dragonfly watchers due to the return to what is perhaps our more usual damp and unpredictable weather. However there were notable highlights.

Earlier in the year, the Club-tailed Dragonfly Gomphus vulgatissimus, perhaps Worcestershire's most important dragonfly, was re-surveyed on the River Avon. In 1993 this dragonfly was not found emerging upstream of Evesham but in May it was found in every 1 Km square beyond Evesham, all the way to Marlcliff and just in to Warwickshire. This constitutes the first breeding record for this species in Warwickshire. It is interesting to note that only one month before this, the River Avon had experienced its worst floods in memory.

In late May Alan Shepherd collected an exuviae (shed larval case) from a pool at Grimley which was later identified as a Club-tailed Dragonfly. This would not have been unusual except for the fact that this species is only very rarely found breeding in still water. Strangely this habit does occur on the continent but not in the British Isles. Here it has only been noted once before and that was on the River Thames, but in that case it was in a pool which gets occasional flood water whereas the one at Grimley was 1 Km away from the river and not in the floodplain.

In June a number of Four-spotted Chasers Libellula quadrimaculata were seen at pools including the same pool at Ombersley where a colony of Marsh Frogs were found. This year the pool was very productive as one of the Skimmers found was the form praenubila Newman which is the variation where there is an additional dark patch on the wing below the pterostigma. It is this dragonfly which has been adopted as the logo of the British Dragonfly Society.

Black-tailed Skimmers seemed more numerous than ever, being particularly found at gravel pits, and one pit at Upton-on-Severn had hundreds flying in August. One exuviae of this species was collected at a pool near Grimley which was 12 metres away from the water proving that if you are looking for larval cases you should also look well away from the water.

On one of the Worcestershire Naturalists meetings at Ripple Pool in mid July, several exuviae of the White-legged Damselfly Platycnemis pennipes were found. This is unusual because it is a river species but nothing like as unusual as the Club-tailed Dragonfly in the same circumstances. This pool used to be a very good site for the Red-eyed Damselfly Erythromma najas but since the plant that it laid eggs in to, Water Bistort, has been removed the species is much reduced in numbers.

No Black Darters Sympetrum danae were seen this year in the County and it probably means that those seen last year came in from outside the area. One of the pools where Black Darters were seen last year, at Mamble, again provided a valuable record with only the second proven breeding record for the Common Darter Aeshna juncea in Worcestershire.

Most notable was the discovery of the Red-veined darter in the County. Two species of red darter dragonflies have sporadically visited the British Isles since the 1900's, the Yellow-winged Sympetrum flaveolum and the Red-veined Darter Sympetrum fonscolombei. Since the mid 1990's these two have become much more regular visitors and it was only a matter of time before both were found in Worcestershire. The first to arrive in large numbers was the Yellow-winged Darter which appeared in 1995 and was seen in 13 localities. Despite the large numbers seen nationally and locally there has been a poor count in the following years and this particular insect looks as though it will be a long time before it becomes established.

The Red-veined Darter has made annual incursions in to the British Isles ever since 1995 and has finally shown up in the south of our county at the Kemerton Estate. Up to nine individuals were seen from 25/7/98 and the last adult was seen on the 22/8/98. The numbers are small and may not sustain themselves but they did show signs of breeding. The origin of the group is uncertain as it is not known whether they arrived as migrants or whether they were the result of egg laying last year.. However, the former is probably the case as over forty exuviae were collected from the pool but none were of the Red-veined Darter. Several other sites where this species were seen were in the south and east of England in Kent, Dorset Cornwall, London and also The Isle of Man. That they do successfully breed in this country has been shown at Dungeness and in Dorset. Whether they bred or not it is nice to add another dragonfly to the list making 25 so far in this County.

The Red-veined Darter is similar in size and colour to other darters and is best distinguished by the red veins along the leading edge in the basal half of each wing. In the females these veins are yellow. There is very little black marking on the sides of the abdomen compared to the Common Darter. The place to watch out for this insect is at gravel pits especially following strong south westerly winds. On the continent this species is mainly found in southern European countries.

Lastly a word of warning. While you may be out trying to decide whether the emperor type dragonfly you just saw might perhaps be a Vagrant Emperor Hemianax ephippiger or a Lesser Emperor Anax parthenope, there is now a new complication because this September the first American dragonfly, a Green Darner Anax junius flew in to Cornwall and The Isles of Scilly. This emperor dragonfly is very numerous in the States and so it was only a matter of time before it arrived in the Country!