Suffolk Lepidoptera in 1983

S U F F O L K L E P I D O P T E R A IN 1983 H . E . CHIPPERFIELD

A mild winter was followed by a very wet spring, and apart from the odd butterfly tempted out of hibernation when we had a little sunshine, it was a generally late start to the season for both butterflies and moths. Mr R. F. Eley saw Inachis io Linn, the peacock in his garden at Nowton, west Suffolk on 5th January, but he said it was a poor season for this species and also for Aglais urticae Linn, small tortoiseshell, both formerly very common insects.

It is likely that the more efficient destruction of their food plant, the stinging nettle, has something to do with this. The spring brood of the 'whites' appeared in mid-May, and in the Walberswick area Pieris napi Linn, green-veined white was decidedly more plentiful than its two relations P. rapae Linn, small garden white and P. brassicae Linn, large garden white.

The summer broods of the two former species were of average size but P. brassicae was quite scarce in both east and west Suffolk, largely because there was a much smaller immigration from the Continent than usual.

It was a good year for Colias croceus Geoff. clouded yellow. This butterfly is a native of the Mediterranean region whence in early spring it annually migrates over central and western Europe, usually arriving in Britain in varying numbers in May or early June. I saw a specimen in my garden on 8th June, Mr. Eley saw a female at Wortwell on 12th June, and a pair at the same site a week later - from which he bred 160 butterflies. On 6th August Mrs. Joan Huxley saw one at Leiston and Wing Commander F. J. French reported one of the pale form (helice) near the mouth of the River Deben on 14th August. Mr Arthur Watchman saw one along the beach between Thorpeness and Aldeburgh on 4th August, another Aying along the main street at Monks Eleigh on 9th, and a third to the west of Lakenheath on 31st of the month.

When all the sightings in connection with the Butterfly Survey have been gathered together 1983 will be shown to have been a good year for this insect.

Mr. Clive Naunton reported a specimen of the rarer Colias hyale Linn, pale clouded yellow at Covehithe on 30th July. This insect is rarely found in Suffolk and could be confused with one of the pale forms of the clouded yellow, but Mr. Naunton, who is a keen observer, is quite certain of his identification.

Gonepteryx rhamni Linn, the brimstone is not a frequent butterfly in the coastal area of Suffolk largely because the foodplant of the larva, buckthorn, is scarce. However, it is a great wanderer and is seen most years. Mr. David Baker reported one at Wangford on 17th March, Wing Commander French saw one on 9th April at Felixstowe and I had a pair in my garden on 16th, where I have a bush of buckthorn. Most of our other resident butterflies were moderately plentiful in both East and West Suffolk. Mr. Eley reported that Pararge aegeria Linn, speckled wood and Pyronia tithonus Linn, gatekeeper were well above average in west Suffolk. He also said that Callophrys rubi Linn, green hairstreak was common over a long period in King's Forest as it was also in the Walberswick area. H e also saw a few Quercusia quercus Linn.

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purple hairstreak and said that Strymonidia w-album Knoch. white-letter hairstreak was very common on the Norfolk side of the border, although he saw none in Suffolk. The purple hairstreak was reported by Mr. Cliff Waller on Walberswick National Nature Reserve and I saw several larvae of the white-letter hairstreak on one of the few remaining wych elms not affected by Dutch Elm disease in Dunwich Forest.

There were many records of Polygonia c-album Linn, comma by the Rev. Nicolas Cribb at Drinkstone, Wing Commander F. J. French in Rendlesham Forest and Mr. Eley who saw them from late April until well into October.

The only example I saw in Walberswick was at ivy blossom on 6th October, and neither Vanessa atalanta Linn, red admiral nor Cynthia cardui Linn, painted lady were as common as usual on either side of the county. Celastrina argiolus Linn, holly blue was present in small numbers in both spring and summer broods and Plebejus argus Linn, silver-studded blue was out in good numbers on Westleton Heath on 7th July. The colony of this butterfly which used to occur on Wenhaston Mill Heath appears to have died out, unless it has moved its headquarters, which this insect and several other species have a habit of doing.

Of a total of about 2,500 lepidoptera on the British list only about 100 are butterflies, and of these at least 50 are rare vagrants, which can hardly be called British. I will turn now to the much more numerous moths.

Mr. Eley noted a few of the geometer Theria primaria Haw. the early moth on his garden hedge at Nowton on 21st January. Only the males of this moth have efficient wings. The females have little stumps of wings which are quite inadequate for Aying. Several of the other winter and early spring moths also have wingless females. He also saw Xylocampa areola Esp. early grey among other species in the King's Forest on 12th March, which he says is a very early date. The larvae of X. areola feed on honeysuckle. Düring the season he saw many different species in the King's Forest, the more interesting being Comibaena bajularia D. & S. blotched emerald, whose oak-feeding larva covers itself with pieces of leaf as protection, Catarhoe cuculata Hufn. royal mantle, Idaea straminata Borkh. piain wave, Perizoma bifasciata Haw. barred rivulet, whose larva feeds on the seeds of red bartsia, Chloroclysta siterata Hufn. red-green carpet, which is rather local in the Eastern Counties.

Among the moths seen in his garden M.V. trap were Eulithisprunata Linn, the phoenix, which has become uncommon in many districts, Philereme transversata Hufn. dark umber, whose larva feeds on buckthorn, Eupithecia denotata Hübn. campanula pug, a local geometer, the larva feeding on the seeds of nettle-leaved bellflower, Ennomos autumnaria Werneb. large thorn, which is continuing to spread, and Lithophane semibrunnea Haw. tawny pinion, a rather local species. At Lakenheath on 8th July Mr. Eley saw Simyra albovenosa Goeze. reed dagger, Epirrhoe rivata Hübn. wood carpet, both local moths, and several hundred Leucoma salicis Linn, white satin moth which he said was like a snowstorm. This insect sometimes occurs in large numbers in the London area where there are poplar trees. Mr. Eley also observed that Operophtera fagata Scharf, northern winter moth far outnumbered O. brumata Linn. common winter moth - a most unusual occurrence in Suffolk. The larvae of O. fagata feed on birch, whereas those of O. brumata

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S U F F O L K LEPIDOPTERA IN 1 9 8 3

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are to be found on many trees and shrubs, including fruit trees.

Mr. Watchman recorded several moths new to his garden moth trap, including Rheumaptera cervinalis Scop. scarce tissue on 7th June, which I have always found more common and widespread than the common tissue in Suffolk, Tethea or D. & S. poplar lutestring on 18th July and Arenostola phragmitidis Hübn. fen wainscot on 31st July, which is abundant in the Walberswick marshes. On 12th October he saw Peridroma saucia Hübn. pearly underwing. This insect is considered to be a resident of the southern counties, but its appearance elsewhere isusually due toimmigration. Hypena rostralis Linn, buttoned snout came to his moth trap on Ist November, so it would appear that this species is making a recovery after being scarce or absent from many districts for some years. It used to be a regulär visitor to ivy blossom in the Stowmarket area. Between 5th and 31st October Mr. Watchman saw 10 examples of Lithophane leautieri Boisd. Blair's shoulder-knot, and I had three at Walberswick between 12th October and 7th November, so it seems that this comparatively new British species has established itself in Suffolk. Mr. Watchman had a pyralid moth Alispa angustella Hübn. narrowwinged knothorn at Monks Eleigh on lOth July. This is only the second recorded specimen for Suffolk; I had the first at Stowmarket in 1949. The larvae feed on spindle berries which they spin together with silk. Other moths recorded at his garden trap were Ptilodontella cucullina D. & S. maple prominent on 12th and 25th July, numbers of the marsh loving pyrale Nascia cilialis Hübn. orange-rayed pearl, Thera juniperata Linn, juniper carpet and Agrotis ipsilon Hufn. dark sword grass. This latter species also appeared in good numbers at Walberswick, reaching a peak of 32 on the night of 30th August/Ist September, due no doubt to immigration..

On Hollesley Common Mr. Watchman again saw Elaphria venustula Hübn. rosy marbled and Stauropus fagi Linn, lobster moth, together with Cycloptera linearia Hübn. clay triple lines, which is 'local' in Suffolk but common where there is a good growth of beech. On the Society's walk along the Icknield Way on 26th June he saw Lithostegegriseata D. & S. grey carpet.

This is a typical Breckland insect found nowhere eise, the larvae feeding on seeds of flixweed. He also said that Diacrisia sannio Linn, clouded buff was abundant. This moth, related to the tiger moths, is easily flushed by day from heaths and was also present on Westleton Heath on 7th July. Also on 26th June, Mr. Watchman found an almost defoliated hawthorn bush on which were pupae of Scythropia crataegella Linn, the local hawthorn ermel in a web. At Market Weston Fen on 8th July he had six species of hawk moths to his light, together with Lithacodia pygarga Hufn. marbled white spot and a number of the micro moth Ethmia dodecea Haw. At Frostenden on 16th July Apeira syringaria Linn, lilac beauty and Ptilodontella cucullina D. & S. maple prominent were recorded. I also had an example of the latter moth at Walberswick on 3rd July where it is not often seen. At the same venue on 5th August he found Xanthorhoe designata Hufn. flame carpet and Celaena leucostigma Hübn. crescent, both the type and ab.fibrosa. Finally at Combs Wood near Stowmarket, a recently acquired reserve of the Suffolk Trust for Nature Conservation, he found a remarkable form of Timandra griseata Peters the bloodvein. Instead of the usual ground colour of whitish ochreous

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it was black with a red tinge, presumably the form known as ab. nigra.

Incidentally, Combs Wood, for long closed to naturalists, is alleged to be the sole Suffolk home of Cerastis leucographa D.& S. the white marked. Claude Morley's note in the 1937 Memoirs states 'Very rare. Combs Wood, near Stowmarket (H. H. Crewe) but not in Nat. 1858; needs confirmation'. An expedition in March or April when the sallow bloom is out might be rewarding.

Among the more interesting moths at Walberswick were Orthosia populeti Fabr. lead coloured drab on 27th April. This is one of the more local of the Orthosia genus, the larvae feeding on aspen. On 28th July and Ist August I had Single examples of Sterrha vulpinaria H. & S. least carpet. This is the third time the species has been recorded in Walberswick. Its normal habitat is on each side of the Thames estuary east of London. On Ist August a specimen of the wismariensis form of Chilodes maritimus Tausch, silky wainscot came to my garden trap. Three noctuid moths were more frequent than usual. Atethmia centrago Haw. centre-barred sallow put in an appearance on 29th August, Agrochola helvola Linn, flounced chestnut on 29th September, and Xanthia aurago D. & S. barred sallow on 4th October. On 9th July Eurrypara perlucidalis HĂźbn. lucid pearl was seen at Walberswick.

This pyrale has spread from Wood Walton Fen where it was discovered by the late Robin Mere in 1951. Eustrotia uncula Cl. silver hook was seen in its boggy haunt at Walberswick on 12th July. This little day-flying noctuid is just holding its own after being almost exterminated by the sea-flooding in 1976.

A male Euproctis chrysorrhoea Linn, brown tail was attracted to M. V. light in my garden on 18th July. This species is sometimes abundant in coastal areas and at Dungeness, Kent this year I saw hundreds of sallow bushes completely stripped by its larvae. Our President, Dr. E. A. Ellis, said he had also heard of an infestation of the brambles at Landguard Common, Felixstowe. These larvae, which are hairy with two prominent red spots, should not be handled as they bring out an unpleasant rash. On 29th July I visited Dunwich Forest with Mr. Terry Dillon, an entomologist from Surrey, to see if Herminia tarsicrinalis Knoch. a species of fanfoot, discovered for the first time in Britain in 1963, had spread from Thorpeness to the bramble thickets there. We were a little late for it but found a few rather worn specimens. Most of the usual autumn moths turned up, but, with few exceptions, in reduced numbers. One such was Rhizedra lutosa HĂźbn. large wainscot which was very common. I had 18 in my moth trap on 4th November and 25 on the 6th.

In addition to migrant butterflies there were also records of migrant moths as follows: A G R I U S CONVOLVULI

llth 12th 24th 26th 27th 27th

Sept.

Sept.

Sept.

Sept.

Sept.

Sept.

3 1 1 1 1 1

Linn, convolvulus

hawkmoth

M r . R . F . E l e y a t Nowton Mr. R. F. Eley at Ixworth Mr. Arthur Watchman at Monks Eleigh Mr. Peter Quinn at Kelsale garden trap at Walberswick Mr. R. F. Eley at Nowton

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SUFFOLK LEPIDOPTERA IN 1983

28th Sept. 1 30th Sept. 1 4th Oct. 1

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Mrs. Joan Holling at Walberswick Mrs. E. M. Hyde at Wolverstone garden trap at Walberswick Linn, hummingbird hawk-moth Wing Commander F. J. French at Felixstowe Ferry Mr. A. Watchman at Monks Eleigh Mr. A. Watchman at Hadleigh Mr. A. Watchman at Felixstowe Mr. A. Watchman at Monks Eleigh in garden at Walberswick

MACROGLOSSOM STELLATARUM

19th June 1 14th Aug. 1 27th Aug. 1 18th Sept. 3 23rd Sept. 1 1

ORTHONAMA OBSTIPATA Fabr.

6th Nov. 1 lOth Nov. 1

the gern in garden trap at Walberswick Mr. A. Watchman at Monks Eleigh

RHODOMETRA SACRARIA Linn,

31st Aug. 1 26th Sept. 1 28th Sept. 1 1 29th Sept. 2 30th Sept. 1 6th Oct. 1 15th Oct. 1 26th Oct. 1

the vestal Mr. A. Watchman at Monks Eleigh Mr. A. Watchman at Monks Eleigh garden trap at Walberswick Mr. A. Watchman at Monks Eleigh garden trap at Walberswick garden trap at Walberswick garden trap at Walberswick garden trap at Walberswick garden trap at Walberswick pink form

UDEA FERRUGALIS Hübn.

3rd Nov. 1 5th Nov. 1

rusty dot garden trap at Walberswick garden trap at Walberswick

The only other migrant moths were many Nomophila noctuella D. & S. rush veneer, which both Mr. Watchman and I found to be common and widespread, and Plutella xylostella Linn, diamond-back moth which was also abundant.

Three species were reported to me by Mr. Bernard Skinner on 18th July near Thorpeness as suspected migrants. They were: Nola aerugula Hübn. scarce black arches Meganola albula D. & S. Kent black arches Eilemapygmaeola Doubl, pigmy footman H. E. Chipperfield F.R.E.S. Walberswick

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