Llanelli Naturalists Newsletter - Summer 1993 - No 55
Ian Morgan
A few years ago, the Dyfed Wildlife Trust - who own most of the Ffrwd Fen Nature Reserve - arranged for the excavation of a small pond near the northern corner of the "Ffrwd Fen triangle" at c.SN418027). Already this pond has attracted uncommon dragonflies such as the spring-flying (May-June) Hairy Dragonfly Brachytron pratense and in winter•is popular with small flocks of Teal. A visit by Richard Pryce on 2 June 1993 revealed the presence of a rarely recorded bug or hemipteran - the water stick-insect Ranatra linearis. This was apparently last recorded in the vice-county of Carmarthenshire at Kidwelly in 1959 by Arthur Price, a school teacher of local extraction who sometimes spent his holidays in the Kidwelly area. He was particularly interested in water beetles but he also noted some noteworthy bugs (both terrestrial and aquatic species). A summary of his coleoptera records is given in the Winter 1959 issue of "Nature-in-Wales" (Price, 1959 (a)). Price's 1959 record (Price, 1959(b)) of the water stick-insect referred to "four nymphs taken on 20th August in a canal near Kidwelly". The water stick-insect can attain a size of c.10 cms including its long ovipositor and Ranatra has an obviously distinctive appearance so is not likely to be under-recorded. It lives amongst water weeds where it feeds on small creatures such as Daphnia.
Another large aquatic bug which occurs in Carmarthenshire is the so-called "water scorpion" Nepa cinerea, a markedly-raptorial species which consumes tadpoles and the like. Whereas the author has never seen the water stick-insect, he has noted the water scorpion on several occasions - at Ffrwd 22/412035 (25.5.1986), Machynys Ponds 21/509983 (22.9.1990),* near the Witchett Pool 22/282076 (7.7.1986) and at the Dinefwr Oxbows, Llandeilo 22/605222 (19.9.1991). Neil Matthew also reports the water scorpion from Talley Lakes 22/632335 and Matt Ridley recently discovered this species in a pond at Gelli Aur Country park 22/592107. Both Ranatra and Nepa have wings, though only Nepa occasionally flies; neither are good swimmers - rather they crawl about on water weeds etc.
*the now-infilled pond which was amongst factory buildings on the western side of the "Cocklers Road"
The last of the trio of large (submerged) water bugs - but excluding the "back swimmers" Notonecta spp - is the "saucer bug" Ilycoris cimicoides, another carnivorous species, which can be found by sweeping amongst dense aquatic vegetation. The Saucer Bug has been noted at Machynys Ponds 21/512980 (13.10.1990), and "cors Pond", Dafen 22/531015, (15.9.1991).
All three of these species are mostly southern in distribution in Britain, neither has been recorded in the other two vice-counties of Dyfed (Pembroke and Cardigan).
For interested readers, further information on these three species is given in Southwood & Leston (1959), including notes on the "death-feigning" reaction of the water scorpion and the water stick-insect - when they become rigid when handled and go into catalepsy.
Recently, whilst engaged on moth trapping survey work late one evening in the Pinged area, Pembrey, Barry Stewart was fortunate enough to come across some glow worms Lampyris noctiluca, shining at the base of a concrete trackway. Clow worms are not worms of course, but beetles. The female beetles, which are rather larvae-like, emit a bright greenish-yellow light from underneath the hind end of their abdomens. The flying males fly in search of the females to which they are attracted by the light. Glow worms are most frequent in snail-rich localities, as the larvae feed on these molluscs. A good illustration of all stages of the glow worm is given in Chinery (1986).
Some years ago an article of mine in the Western Mail prompted some readers to write in to offer their records of glow worms. About a dozen records were from Carmarthenshire (dating from c1935 to the mid 1980's).
There have been several subsequent sightings, the majority of which are by Neil Matthew, perhaps currently the most nocturnal of the county's naturalists and noted for his work on bats and otters. These Carmarthenshire records are listed below.
Nr Llanllwch 22/388191 c1980 M. Dunn
Felindre 22/685306 1983 Mrs Vanessa Hope-Bell
Commissioners Bridge, 22/410056 16.5.1987 I.K. Morgan (larvae record)
Kidwelly
Pant-y-llyn 22/605167 1989 N.R. Matthew
Nr Penybanc, Abergwili 22/437219 1989 D. Julian
Gorslas 22/563134 July 1990 N.R.M. 22/569133
Mynydd Llangyndeyrn 22/483131 July 1990 N.R.M.
Nantgaredig 22/47-21- 1990 N.R.M.
Porthyrhyd 22/715366 1 July 1991 N.R.M.
Brechfa Forest 22/485290 - 21 July 1991 N.R.M.
22/483288
Crychan Forest 22/837427 June 1992 J.Friese, R.O.Hunt, B.Stewart
Nr Derwydd 22/613175 May 1992 N.R.M. (larvae record)
Pinged 22/426033 4 July 1993 B.Stewart
A note (Anon, 1992) in a recent issue of the Dyfed Wildlife Trust Bulletin suggests that the only Carmarthenshire record is one from the R.S.P.B. Dinas Reserve [22/78-46-) in July 1968, but the official Biological Records Centre (BRC) scheme organized by Dr Keith Alexander shows far better coverage than this (Alexander, 1990). All records collated by the author are sent to the SRC scheme.
Whilst there may well have been a decline due to habitat loss (eg snail-rich calcareous grassland) or successional changes (tree growth shading out sites), a reduction of recent records may be due to the fact that the public and most naturalists perhaps spend less of their summer evenings out of doors, due to the advent of television or whatever reason. consequently, a whole range of crepuscular wildlife may be missed - high flying Noctules, "churring" Nightjars or rarely, singing Spotted Crakes in marshy habitats - as well as glow worms. Certainly, Barker (1905) noted that the glow worm "occurs not uncommonly in our country lanes", without citing any locality and Brunker in his manuscript "Natural History of Llanegwad Parish" (c1950) offered one record: "on the gravel near the roadside on the old Brechfa road".
Dafydd Davies in one of the very useful lists of Welsh names for familiar wildlife (and sometimes taxonomic groups) in Y Naturiaethwr (Gorff. 1987: No18 p18) gives several names for the glow-worm (hence part of the title of this article) including:
Jac a lantern. Jack with the Lantern
Pryf Tan Fire Insect
Tan Bach Diniwed - Harmless little fire
Pryf Golau Light Insect
Bwgien Little Ghosts
Pry'_ Gwreichion - Spark Insect
"Jac a lantern" is the name used in SW Wales.
*NB Any additional glow worm records would be appreciated.
REFERENCES
Alexander, K.N.A. (1990). - Cantharoidea & Buprestoidea Recording Scheme, Newsl. No3 (May 1990): 2 & 5.
Anon (1992) Glow little Glow-worm. Dyfed Wildlife Trust Bulletin k 59t(Septth1:92)Nalt:
Barker, T.W. (1905). Handbook Natural History of Carmarthenshire. W. Spurrel & Son, Carmarthen. Brunker, J. (c1950). Natural History Section. Unpublished manuscript notes. Carmarthenshire Record Office (CDX/259/11).
Chinery, M. (1986). Collins guide to the Insects of Britain &Western Europe:270-271
Davies, D. (1987). Enwau Cymraeg ar Greaduriaid - Eisteddfod
Abergwaun 1986. Y Naturiaethwr Rhifyn 18:18 Kirby, P. (1991). A Provisional List of the Heteroptera of Carmarthenshire. Dyfed Invertebrate Group
Newsletter 23: 6-17. Price, A. (1959(a)). The Hydradephaga of the Kidwelly district of Carmarthenshire. Nature in Wales 5,No4:843-848 " (1959(b)) In Field Notes: Bugs. Nature in Wales 5, No4:861
Southwood,T.R.E. & Leston,D. (1959) - Land and Water Bugs of the British Isles. Warne.