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Libellula fulva Muller Scarce chaser
Description L. fulva is one of the four libellulids in which mature males possess a pale blue
pruinescence on the abdomen. In L. fulva this extends over abdominal
segments 3-7, leaving the anterior two and posterior three segments black.
This black tip to the abdomen is noticeable in flight and helps distinguish it
from mature male Orthetrum coerulescens and from L. depressa (segment 10
in L. depressa is dark but so small as to be scarcely noticeable in flight, and its
abdomen is much broader than that of L. fulva). At the base of the wings is a
dark black-brown patch, much reduced in the forewings, which distinguishes
L. fulva from 0. coerulescens and 0. cancellatum, in which the wings are clear.
The thorax is dark brown and hairy, and the eyes are blue-grey. Females and
immature males lack the blue pruinescence. They have a rich orangeamber-coloured
abdomen with black triangular marks mid-dorsally on
segments 4-10. The wings possess a black basal patch and bright orange
veins which extend towards and sometimes beyond the nodes, but lack the
black nodal marks of L. quadrimaculata. However, female L. fulva do possess a
dark patch at the apex of each wing, sometimes much reduced; this is
sometimes apparent in males. It should not be confused with L.
quadrimaculata f. praenubila. The thorax is amber-brown and the eyes are
grey-brown.
Habitat L. fulva breeds on unpolluted rivers and dykes with slight to moderate flow, and
occasionally in static water habitats such as mature gravel pits which are at
least 20 years old (Milne 1984). It prefers stretches of riverbank which contain
patches of tall emergent vegetation such as common club-rush, reed sweetgrass
and branched bur-reed, as well as small areas of yellow water-lily.
Breeding biology The male is territorial. Its highest steady density is about 9 per 100 m of
water's edge when males are active, but in late evening several may perch in
close proximity Copulation occurs amongst riverside vegetation, and can take
over 15 minutes. The female oviposits whilst hovering, and strikes the water
every few seconds with the tip of her abdomen so releasing the eggs, often
staying over the same spot for several minutes. The male usually hovers
nearby to ward off intruding males. The larvae, which probably take two years
to develop, live in the bottom silt and mud. Emergence is synchronous.
Flight periods L. fulva has a short flying season from the end of May to mid-July. It may be
Status and distribution
European and world
distribution
seen with Platycnemis pennipes, Calopteryx splendens and Gomphus
vulgatissimus on rivers, and with Coenagrion pulchellum and Brachytron
pratense on grazing marsh dykes.
L. fulva is a scarce dragonfly in Britain. It breeds on a few scattered river
systems and nearby still-water sites. It occurs on the River Avon in Wiltshire
and in Somerset; the Rivers Stour, Frome, Moors River, and Avon in Dorset (and
Hampshire border in the latter river); the River Arun in Sussex; the North
Stream and associated ditches near Sandwich, Kent; the Rivers Nene and Ouse
and nearby gravel pits and fen dykes in Cambridgeshire; and grazing marsh
dykes associated with the River Waveney in Suffolk and the River Yare in
Norfolk. L. fulva bred for many years at Shirley Pool near Askern in Yorkshire,
but has not been seen there since 1911. There are old records from Deptford
and Bermondsey marshes, 'east of London', from the early 19th century L.
fulva has been recorded from Ireland only once. A male taken at Dingle, Co
Kerry, in 1849 by 'R W' (probably Richard Weaver) is in the Dale Collection in
Oxford (Lucas 1908). L. fulva is vulnerable to pollution of the rivers and
drainage channel systems in which it breeds. It occurs on several NNRs and
RSPB reserves.
On the continent, L. fulva is widely but locally distributed from the south of
France to north Germany, and east through central Europe to Russia. It is rare
in Spain and has been reported only from the extreme south of Scandinavia.
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