Llanelli Naturalists Newsletter - May 2007 - No 7
Ian Morgan

The white-letter hairstreak is a local species in Carmarthenshire, this reflecting the distribution of elms in the county The Millennium Atlas shows no records, but this is because they were not entered by the then county coordinator, as sadly were other important and valid records of scarce species.

The probable first record of white-letter hairstreaks in Carmarthenshire hail from 1947, when Davies (1954) noted it in 'considerable numbers' near Ferryside SN30, whilst in July 1952 Thomas (1952) took a specimen near Carmarthen SN 42 and he also stated that 'others' were seen in the woods near Cynwyl Elfed (SN 37-27-).

Mark G Williams observed an adult on bramble blossom beside the road SN 488015 going through Stradey Woods, just west of Llanelli, on 3.8.1975; he saw another at the same site in August 1976. Also, on 4.7.1976, MGW noted an individual at his home at Pwll SN474011, feeding on 'honey dew' on a garden apple tree. Later. (Aug. 1976) yet another was seen by the same recorder at the nearby 'Ffordd y Wagen', Pwll SN 468013. At the Stradey Woods, Pwll and the 1947 Ferryside localities, the elms are once more thriving, as indeed they are in other parts of the county and they do not seem to be suffering again from periodic DI=D

The 1950's records of Thomas and two more recent records by Tom and Gwen Heal at Pont Ynyswen, Brechf a SN 533275, probably refer to populations of white-letter hairstreaks that are dependent on trees of the native wych elms, which is a regular component of the more base-enriched wooded dingles. More recently, Neil Matthew has been recording white-letters in the mid Tywi Valley.

Given that the English elms of the flat coastal belt, the scattered wych elms of the woodlands and the hedgerow elms of the Tywi and Teifi valleys are once more doing well, we can perhaps expect the same to apply to the white-letter hairstreak. We now need to resurvey old sites and check potential new ones!

References:

Davies, D.A.L (1954) - Some records of Odonata and Lepidoptera in Wales. Entomologists Gazette, 5:1D3-4,

Morgan, I.K. (1989) - A Provisional review of the Butterflies of Carmarthenshire. Unpublished report, Nature Conservancy Council: 34-5.

Thomas, D.L. (1952) - Notes on Carmarthenshire Butterflies. Entomologist, 85: 143-4.