Suffolk Lepidoptera in 1981

SUFFOLK LEPIDOPTERA IN 1981 H . E . CHIPPERFIELD

In this 'Year of the Butterfly' there seems to have been a great Variation in numbers both of species and individuals. Anthocharis cardamines Linn., the orange-tip, was around in its usual numbers in May and Celastrina argiolus Linn., the holly blue, was quite common in both the spring and summer broods. Pieris brassicae Linn., the large garden white, was fairly plentiful in the spring, but the autumn brood was not nearly as common as usual as there did not appear to be the customary immigration. Both Pieris rapae Linn., the small garden white, and Pieris napi Linn., the green-veined white, were in good numbers in both broods.

Cynthia cardui Linn., the painted lady, was seen at Walberswick on the 6th June but few were observed in the autumn although several were seen at the Bird Section outing at Santon Downham on 17th October, where between 20 and 30 Polygonia c-album Linns., the comma butterfly, were also seen. This butterfly was also reported by Mr. Derek Moore who saw 3 hibernated examples at Elveden on 17th April. Mr. S. Beaufoy also saw a number in the Ipswich area. Both sexes of Plebejus argus Linn., the silverstudded blue butterfly, were still about on Westleton Heath on Ist August.

Mr. R. F. Eley of Nowton said that the 'whites' and most of the 'browns' were rather less common than usual, except for Pararge aegeria Linn., the speckled wood, which was quite common in mid-June in Kings' Forest and Hipparchia semele Linn, which was fairly common in the autumn.

The earliest moths to make an appearance were Agriopis leucophaearia D. & S., the spring usher, and Apocheima pilosaria D. & S. ( = Phigalia pedaria Fabr.), the pale brindled beauty, on the 7th February, followed by Theria primaria Haw. ( = rupricapraria), the early moth, on 7th March, a hibernated Conistra vaccinii Linn., the chestnut, on the 9th, Biston strataria Hufn. the oak beauty on the 24th and Rheumaptera cervinalis Scop., the scarce tissue, on the 30th of the month. This last species belies its English name as, in Suffolk at any rate, it is far more frequent than its relation Triphosa dubitata Linn., the common tissue. The larva of R. cervinalis feeds on Berberis vulgaris and is found in the same area near Bury St. Edmunds where Pareulype berberata D. & S., the barberry carpet, is found. P. berberata is a very local insect and the Suffolk colony is probably the only one left in Britain. Several years ago, when its habitat was threatened by development, steps were taken to establish a colony in what was considered a safer area. This experiment failed, but the insect is still to be found in its original area although in reduced numbers. I understand it is likely to be put on the 'endangered species' list.

Other moths peculiar to the Suffolk and Norfolk Breck are Lithostege griseata D. & S., the Breckland grey carpet, which is still quite plentiful where its foodplant the flixweed grows, but Emmelia trabealis Scop., the spotted sulphur, which used to be plentiful at Mildenhall has not been reported from that district since 1954, and Hadena irregularis Hufn., the

Trans. Suffolk Nat. Soc. 18 part 4.

287 viper's bugloss moth, whose larva feeds on Silene otites, the Breckland catchfly, has not been reported for several years.

Several lepidopterists visited the Walberswick and Southwold district from other parts of the country during August. Mr. Mark Hadley from the Nature Conservancy H.Q. came on the 3rd August and ran his M.V. light on the Walberswick National Nature Reserve (by permission of Mr. Cliff Waller the Warden). His list of moth species totalled 63, and included Archanara neurica Hübn., the white-mantled wainscot, Euxoa cursoria Hufn., the coast dart, and Euproctis chrysorrhoea Linn., the brown-tail.

Mr. John Fenn from Norfolk found Photedes elymi Treit., the lyme-grass wainscot. quite plentiful on the Southwold sandhils on 27th July, and Mr. John D'Arcy from Wiltshire reported Photedes brevilinea Fenn., Fenn's wainscot, Archanara dissoluta Treit., brown-veined wainscot, Apamea oblonga Haw., crescent striped, and Simyra albovenosa Goeze., the powdered wainscot, among the 34 species seen.

In my 1980 article I said that I had heard of no reports of Chloroclvstis chloerata Mab., the sloe pug, from Suffolk. Mr. Rafe Eley of Nowton now informs me that he found it in West Suffolk at Hawstead in 1973, but I have still heard nothing of its occurrence in East Suffolk. Mr. Eley also saw about 50 examples of Rhyacia simulans Hufn., the dotted rustic, at his garden M.V. light. This species is extending its ränge and has obvi'ously a strong breeding colony in West Suffolk. In his review of lepidoptera in West Suffolk Mr. Eley said that most species were very much below average in numbers in 1981, the exceptions being Agriopis leucophaearia D. & S., spring usher, and Orthosia cruda D. & S., small quaker, both of which were quite common. Even the common Hawk moths were seen only as Single specimens. He did, however, see several examples of Adscita statices Linn., the forester, in Kings' Forest which he says is a moth which is undoubtedly on the increase.

Mr. Arthur Watchman, who recorded Lithophane leautieri Boisd., Blair's shoulder-knot, for thefirsttime in Suffolk in 1980, saw some more of this newcomer to the county at his garden trap in Monks Eleigh. It appears therefore that the insect has established a colony in its extended ränge. In his garden he also saw a number of interesting species of moths, including Philodontella cucullina D. & S., maple prominent, Parastichtis suspecta Hübn., the suspected, Nycteola revayana Scop., oak nycteoline, Selen ia lunularia Hübn., lunar thorn, Ennomos autumnaria Werneb., large thorn, Apeira syringaria Linn., lilac beauty, Schrankia costaestrigalis Steph., pinion-streaked snout, Hoplodrina ambigua D. & S., Vine's rustic, and the two local pyralid moths usually found in marshy districts, Eurrhypara perlucidalis Hübn., lucid pearl, and Nascia cilialis Hübn., orange-rayed pearl. At other sites at Lakenheath he found Lithacodia pygarga Hufn., marbled white spot, which is not common in Suffolk. At the well-known site near Bury St. Edmunds he and his wife Janet saw one Pareulype berberata D. & S., barberry carpet, and a number of Rheumaptera cervinalis Scop., scarce tissue. On Hollesley Common on 3rd July he recorded a number of species, the more interesting being Perconia strigillaria Hübn., grass wave, Idaea sylvestraria Hübn., dotted border wave, and Elaphria SUFFOLK LEPIDOPTERA IN 1981

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Suffolk Natural History, Vol. 18, Part 4

venustula HĂźbn., rosy marbled, a very local small noctuid moth not recorded in Suffolk since the late P. J. Burton found 3 examples near Blythburgh Fen Wood in 1937, except for a Single specimen reported by Mr. R. Berry at Minsmere in 1978. The larva feeds on cinquefoil and the moth flies at dusk and is very difficult to follow, so it may have been overlooked in some of its haunts. Other very local insects found by Mr. Watchman were the tortrix Falseuncaria degreyana McLach., pink-edged conch, at Pashford Poors Fen. This is practically confined to the Breck District. He also found a specimen of the tortrix moth Pammene trauniana D. & S., Traun's black and white piercer, whose larva lives inside maple seeds. Mr. Watchman pointed out that Morley did not include this insect in his 1937 list, but he did say that it occurred in Cambridgeshire and was likely to be discovered in Suffolk.

In what was considered to be a very poor year for lepidoptera generally, apart from the discovery of a new geometer moth in Kent, migrants were also few and far between. Mr. Eley saw only a few Autographa gamma Linn., silver-Y, and a Single Agrius convolvuli Linn., convolvulus hawkmoth. An example of this latter insect was also reported from Brampton by Dr. E. A. Ellis (Ted Ellis of the B.B.C. in the 'Weekend' programme). The only migrants Seen in Walberswick, apart from a few painted lady and red admiral butterflies, were several Nomophila noctuella D. & S., rush veneer, and quite a lot of the tiny Plutella xylostella Linn. (= maciilipennis Curt.), diamond-back moth, whose larvae are sometimes destructive to cabbages.

Altogether a very lean year from the lepidopterist's point of view, but in 1982 we hope for another good season like that in 1976.

H. E. Chipperfield, F.R.E.S., Walberswick, Suffolk.

Trans. Suffolk Nat. Soc. 18 part 4.