Suffolk Lepidoptera, 1966

SUFFOLK LEPIDOPTERA, 1966 H.

E.

CHIPPERFIELD

THE mild weather in January and February brought out the early spring moths well up to average dates and on 6th February there were quite a lot on the wing. Düring a Bird Section outing to Benacre and Southwold on 6th March a Brimstone butterfly ('Gonepteryx rhamni, Linn.) was seen. The Orange Underwing moth (Archiearis parthenias, Lin..) was on the wing near Mayday Farm in the Breck District on 13th March. The Orange-tip butterfly (Anthocharis cardamines, Linn.) was first seen at Norton on 30th April, but I saw no specimens of the first brood of the Holly Blue butterfly (Celastrina argiolus, Linn.) and only one of the second brood at Great Finborough on 22nd September. This little butterfly has been reported as becoming scarce by quite a number of observers in different parts of the country. Düring the first week in May numbers of the Sulphur-underwinged Tubic (Dasycera sulphurella, Fabr.) emerged from some decaying logs.

It seems stränge that such an attractive little insect should spend its larval stage in rotten wood. Several delicately coloured Pyrales have a similar habit.

It was not until the 22nd May that night-flying moths appeared in any numbers and among them was a perfect specimen of the Hebrew Character (Orthosia gothica, Linn.)—a very late date for this moth which is normally out in March and early April. On 29th May the local little Sulzer's Longhorn (Adela croesella, Scop.) was to be seen sunning itself on the elm leaves at Barton Mills. This moth is very much like a smaller edition of the common Degeer's Long-horn (Nemotois degeerella, Linn.), but is much more difficult to see. A Painted Lady butterfly (Vanessa cardui, Linn.) was seen at Stowmarket on the same day. Subsequently I learnt that many of these butterflies had appeared nearer the coast. As numbers of immigrant moths including the Silver-Y (Plusia gamma, Linn.) and Rush Veneer (Numophila noctuella, Schiff.) were found in the light trap a few nights later, an immigration on a considerable scale must have taken place.

Larvae of the Painted Lady were subsequently found in numbers on thistles near the coast by Mr. G. L. Ransome, who kindly brought some to me. These emerged in due course and were released at Walberswick. A specimen of the Cloudy Wormwood Pearl moth (Ostrinia nubilalis, Hübn.) was taken at Stowmarket on 2nd July. This species, known also as the European Cornborer seems to be spreading from its first foothold at Benfleet, Essex, where the larva feeds in the stems of mugwort. Once again several True-lover's Knot moths (Lycophotia varia, Vill.) appeared at Stowmarket in perfect condition. As the nearest wild heather, the larval food-plant, is at least twelve miles away it must be

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concluded that this species is breeding locally on cultivated heathers in gardens. This is unusual, as many heather-feeding larvae will not touch the cultivated kinds. Mr. C. W. Pierce took a specimen of the Beautiful Twist (Lozotaeniodes formosana, Fröl.) at Needham Market on 14th July, which he kindly handed to me. This is only the second specimen of this recently discovered tortrix to be recorded for Suffolk.

From 18th to 3Ist July I was in Scotland. One of my quarries was the Gold Spangle moth (Plusia bractea, Schiff.) which I found in the Lake District as well as at Rannoch and Rothiemurchus.

I was not, however, prepared to find a perfect specimen of this moth in my light trap at Walberswick on 8th August, Over a week after my return from Scotland. This is a new record for Suffolk.

Düring August and September large numbers of moths were attracted to mercury vapour light at Walberswick. These included several species of Wainscots for which the local marshes are noted. In addition two specimens of the Small Mottled Willow (Laphygma exigua, Hübn.) appeared on 12th August. This is an immigrant species which was introduced into the United States and is known as the Beet Army-worm to American economic entomologists. In India the larva is destructive to maize and other crops, but when larvae are obtained in this country they can be reared on weeds such as plantain, dandelion, and groundsel.

A specimen of the Marbled Yellow Straw Pearl (Evergestis extimalis, Scop.) was taken on 26th August. This is only the second specimen of this very local moth I have seen, both near the coast.

All the records in the 1937 Memoirs were from the Breck District, where it is sometimes quite common.

Numbers of the Pearly Underwing moth (Peridroma porphyrea, Schiff.), the Rusty Dot Pearl (Udea ferrugalis, Hübn.), the Rush Veneer (Nomophila noctuella, Schiff.) and the Diamond-back Smudge (Plutella maculipennis, Curt.) appeared at Walberswick in September and early October. These are all species which migrate periodically. Ä larva, which from the description given to me must have been that of a Death's Head Hawk moth (Acherontia atropos, Linn.) was reported from Walberswick in September, and a new member, Mr. R. F. d'A. Willis of Higham, took a Convolvulus Hawk moth (Herse convolvuli, Linn.) in a moth trap there on 12th September.

Düring early June Messrs. S. Wakely and J. M. Chalmers-Hunt and Col. Emmet were at Thorpeness and reported two specimens of the Concolorous Wainscot (Arenostola extrema, Hübn.). In the 1937 Memoirs Claude Morley knew of no records of this species for Suffolk and wrote "We may hope to add this species to the Suffolk list." They also reported a specimen of the Lace Border moth (Scopula ornata, Scop.) which Morley said was

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"curiously rare, considering the extent of our chalk." He mentions one specimen at Southwold in 1902 and says he had never seen it in Suffolk himself. They also added the Summer Grey Smoke {Luffia lichenosa, Geoffr.—lapidella auct.) to the Suffolk Iist, finding the larval cases on some cement posts. T h e 1937, Memoirs do not include this species, but say "Surely other kinds await discovery, e.g., the Essex Luffia lapidella."

Although I saw no Clouded Yellow butterflies myself I was told of one being seen in Suffolk and certainly Painted Ladies and Red Admirals were more common than usual this year. When all the records are collected it is likely that 1966 will be remembered as a good year for immigrant lepidoptera.