Environmental Engineering Reference
In-Depth Information
dunegentianfallswithinthenormalrangeofvariationofautumngentian.Thereisthesuspiciontherefore
that the dune gentian may not in fact be a separate species, but this does not reduce the importance of
conserving these special populations and the habitat in which they occur.
FIG
89.
Dune gentian, a species that is rare or declining throughout its range, but which occurs in large numbers at
Whiteford and Oxwich. (Harold Grenfell)
In slacks dominated by creeping willow, as at Whiteford Burrows, the bright red leaf beetle
Chryso-
mela populi
, which looks like a large unspotted ladybird, is often common, while the flowers are visited
bytheminingbee
Colletescunicularius
andthehoverfly
Eumerussabulonum
.Plant-suckingbugsinclude
the local species
Globiceps cruciatus, Monosynamma sabulicola
and
Macropsis impura
. Also common
in some slacks is the crimson and black five-spot burnet moth
Zygaena trifolii
, a day-flying species of
high summer. Open, wetter slacks contain important groups of wetland flies such as
Dolichopus notatus
and
Hercostomus nigriplantis
.Inthe wet slacks can also befoundthe aquatic larval stages ofdragonflies,
mayflies and caddis flies, together with water boatmen, the pond skater
Gerris lacustris
and whirligig
beetles.
