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Gomphus vulgatissinius (Linnaeus) Club-tailed dragonfly
Description G. vulgatissimus is a medium-size dragonfly in which the coloration is black with areas of
Habitat
Status and distribution
European and
world distribution
pale lime-green and yellow It bears a superficial resemblance, amongst British
dragonflies, to Cordulegaster boltonn but is much smaller and the pattern of pale
markings is quite different. G. vulgatissimus differs from all other British Anisoptera in
that its pale greenish eyes are not contiguous dorsally In both sexes, the thorax and
anterior segments of the abdomen are extensively marked with pale lime-green to
yellow markings. The posterior abdominal segments are not so heavily marked dorsally,
but do possess a bright yellow mark laterally on each of the expanded segments 8 and
9, which is very distinctive. This lateral expansion, especially noticeable in males, gives
the body a clubbed appearance — hence the vernacular name.
G. vulgatissimus breeds in unpolluted rivers of moderate to slow flow, the depositional
nature of which provides the silt or mud in which the larvae live. On the continent, G.
vulgatissimus breeds also in static water of ponds and lakes, and Kemp (1988) records
an example of this in Shropshire.
Breeding biology There is some doubt about the extent to which G. vulgatissimus is territorial. Mating can
take place far away from water (Moore 1991b). On the River Severn, it exhibits a
preference for sheltered 'mill-pond'-like stretches of river where the water is slow
flowing and in close proximity to woodland or scrub (Kemp & Vick 1983). During
oviposition, the females fly very low over these quieter reaches of river, unaccompanied
by males, and drop their eggs into the water while in flight, sometimes just touching the
surface with the tip of their abdomens. The larvae live in the bottom silt and mud, and
probably take three or more years to develop. G. vulgatissiMus is a spring species with
a synchronous emergence. As a result, its presence on a river can often be noted
because of the numerous exuviae on riverside herbage, the trunks of trees or directly
on the soil of the river's bank. Unlike other Anisoptera, they can emerge in a horizontal
position. Locating exuviae is most easily accomplished in areas of river that flow
through pasture rather than arable land. This is because the cattle trample the bankside
vegetation while drinldng, thus creating open sandy areas over which the larvae crawl to
emerge on the bank or amongst the loose vegetation. Dispersal is invariably away from
the river, and adults can be seen flying in woodland rides or along hedgerows several
kilometres from the river.
Flight periods G. vulgatissimus has a short flying season from mid-May to early July. It is commonly
found with Platycnemis pennipes and Calopteryx splendens.
G. vulgatissimus is confined to seven river systems in southern Britain, namely: the
Rivers Thames, Arun, Dee, Severn, Wye, Tywi, and Teifi and their tributaries. It formerly
bred on several rivers in the New Forest area including the River Oberwater and the
Moors River, but has not been seen there since 1970. A male and a female, now in the
Natural History Museum, London, were captured at Castor Hanglands, Cambridgeshire,
on 1 June 1951, but a search of the nearby River Nene has not so far proved successful.
Several G. vulgatissimus were seen, and one taken, in June 1939 at an unnamed location
about a mile from the River Darent in Kent (Longfleld 1949b). G. vulgatissimus has not
been recorded authentically from Ireland. However, a specimen marked as Irish exists
in the Trinity College Museum, Dublin (King & Halbert 1910). According to King and
Halbert, this was probably taken by Miss Ball (a celebrated Irish entomologist of the
early 19th century) who had no doubt that the species occurred in Ireland. They
speculate that the specimen may have come from the Youghal district in the south,
where Miss Ball spent some time collecting dragonflies. Certainly, the River Blackwater
near Youghal looks suitable for this species, which can easily be overlooked. G.
vulgatissimus is vulnerable to pollution, and to the increased use of rivers by pleasure
boats, the wash from which can dislodge and drown large numbers of emerging adults
in May
On the continent, it occurs in many central and northern countries from France and
northern Italy to southern Scandinavia and east to Russia. It is scarce in the
Mediterranean region.
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