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Aulacidea tragopogonis
A distinctive gall causing considerable
distortion to the leaf which becomes
inflated and spherical and often reddened,
about 2-3cm in diameter. The species
occurs in a variety of habitats from
deciduous woodland to heathland. The
galls were apparently once eaten in France
(Swanton, 1912).
The adult has a distinctive patch of
pubescence on the second segment of the
gaster. The pronotum is longitudinally
striate and pubescent.
Genus PERICLISTUS Foerster, 1869
Gall wasps of the genus Periclistus are generally regarded as inquilines in the galls of Diplolepis
spp. (see below). However there have been reports of secondary galling in at least one species.
Periclistus caninae (Hartig, 1840)
Host: galls of Diplolepis spp.
lkm.sq. records: 3 Indeterminate
The presence of larvae of P. caninae causes enlargement and distortion of the galls of Diplolepis
eglanteriae (Cameron, 1893), and perhaps other Diplolepis spp.. Distorted pea galls have been
found at three sites in the county and P.caninae reared successfully in one case although it was
not possible to rear the original gall inducer.
Genus XESTOPHANES Foerster, 1869
Gall wasps of the genus Xestophanes initiate galls on Potentilla spp. Adult insects have weakly
lobed claws and the subcosta and radius reach the anterior margin of the wing.
Xestophanes brevitarsis (Thomson, 1877) lkm.sq. records: 4 Scarce
Host: Potentilla erecta (L.) Rausch. Tormentil, Potentilla anglica Laich, Trailing tormentil
Part galled: stem, petiole
The few known records seem to indicate a preference for a heath type of habitat: Tiptree Heath;
Honey Lane Plain in Epping Forest, Rochford and Thorpe Green. There is also a record from an
ancient woodland at Hadleigh Great Wood. The Thorpe Green and Rochford records are of
interest as the host plant there is Potentilla anglica.
Essex Naturalist (New Series) 16 (1999)