South Gower Cliffs - Gower - page 97

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Additional species associated with rock-rose are the flea beetle Aphthona herbigrada , the seedbug
Macroplax preyssleri , which is only known in Wales from Overton and Horton cliffs, and the nationally
scare pollen beetle Meligethes solidus , recorded from Mumbles Head and Overton Mere.
Thecoastaljunipercoloniessupportacharacteristicfaunathatincludesjuniperaphid Cinara juniperi ,
juniper shieldbug Elasmostethus tristriatus and two moths, juniper carpet Thera juniperata and juniper
pug Eupithecia pusillata . In addition there are several species of micro-lepidoptera and flies that are
known to be specific to juniper and which are internal feeders on the shoots, leaves, fruits and buds, but
there have been no studies of these in the area so far.
GowerisalsooneofthetwentyoutstandingBritishlocalitiesforcricketsandgrasshoppersandrelated
insects, with sixteen species having been recorded including grey bush cricket Platycleis albopunctata ,
Lesne'searwig Forficula lesnei ,andtawnycockroach Ectobius pallidus .Speciessuchasthese,whichare
only found in the vicinity of the coast, still have a restricted distribution thought to result from the forest
cover that was present when they arrived in Britain during the early postglacial period. For some reason
they been unable to spread inland since the forest was cleared. Interestingly, on the continent they show
no preference for coastal areas.
The grey bush cricket is a nationally scarce insect, but it can easily be found in Gower when active
and calling in warm weather; it is harder to find when conditions are cooler. The colonies are at their
peak between late July and September and in comparatively warm areas, such as the peninsula, a few in-
dividuals may persist into November. Lesne's earwig is also a rare and nationally scarce species that can
be found in reasonable numbers in the area. It is particularly associated with old hedgerows or areas of
scrub, especially where there is traveller's-joy or wild clematis Clematis vitalba , but this is by no means
the only habitat and areas of tall herbage along the coast are also worth checking. Unlike the common
earwigs it has much-reduced hind wings and so cannot fly. Areas of limestone scree along the coast sup-
port the mottled grasshopper Myrmeleotettix maculatus . This insect, whose song is said to resemble an
old-fashioned watch being wound up, has a distinctive marbled appearance.
Cockroaches are a mainly tropical group of insects allied to the grasshoppers and crickets. While the
most familiar species are those associated with human habitation, the three species of small native cock-
roaches are less well known. On the whole, these are secretive insects and much smaller than their larger,
notorious cousins. Even the dusky cockroach Ectobius lapponicus , which is the largest, is only 11 milli-
metres in length. It is very difficult to distinguish adult females of this species from those of the tawny
cockroach. The latter is found in a wide band across southern England, but only two colonies, the one
in Gower and another recently discovered in Suffolk, are north of the Thames. Of the native species it is
the least specific in its choice of habitat and can be found in woodland rides and clearings, in calcareous
grassland, heathland and coastal dunes. More research is needed to determine the extent of the tawny
cockroach in the peninsula and whether other species are also present.
Fewbutterfliesaretruespeciesofcoastalcliffs,butliketheotherinsectstheyoccupyarangeofhabiti-
atsthatprovideanabundanceoffoodandnectarplantsandwherethestructuralfeaturesofthevegetation
provide suitable microclimates for larval growth, mating, egg laying and roosting. Species recorded from
thecoastincludesmallblue Cupido minimus ,therebeinganumberofcolonieswherethelarvalfoodplant
kidney vetch is found, brown argus Aricia agestis , wall brown Lasiommata megera , grayling Hipparchia
semele , small pearl-bordered fritillary Boloria selene and dark green fritillary Argynnis aglaja . Whereas
thestrongestpopulations ofthesmall pearl-bordered fritillary areassociated withthelargerareasofcom-
mon land the dark green fritillary is more of a coastal butterfly, although populations do occur inland in
situations similar to those used by the former species. The adult dark green fritillaries have a preference
for purple flowers as sources of nectar, such as knapweeds and thistles.