Notes and comments on some Suffolk moths in 1995

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Suffolk Natural History, Vol. 32 NOTES AND COMMENTS ON SOME SUFFOLK MOTHS IN 1995 M. R. HALL

We have to go back to 1990 to find a moth report that does not Start by bemoaning the cold spring, slow start to the season and in many cases a poor autumn. Unfortunately, 1995 did not break the mould, but it was somewhat different with that spell of glorious hot weather which started at the end of June, continued virtually unbroken throughout July and almost on to the end of August. DĂźring those eight or nine weeks we saw many migrants and also several resident species in much larger numbers than in recent years.

The most exciting migrant of the year was the oak processionary moth, Thaumetopoea processionea, whose arrival in August added a new species to the list of Suffolk lepidoptera. Within the space of eight days no less than five of these migrants had arrived from the continent. The first three were all recorded in Felixstowe on the night of August 3rd - one by Jon Nicholls at his home in Berners Road and two at Landguard Bird Observatory by Nigel Odin and Mike Marsh. The first was determined by the county recorder, Arthur Watchman, and the other two (one of which was shown at the annual exhibition of the British Entomological and Natural History Society) by Roger Kendrick and Paul Waring. Subsequently a third specimen was recorded at Landguard on August 1 Ith and on the same night the fifth specimen was noted at light in Shottisham (AW). This species is widespread in Europe but does not occur in the British Isles nor the north German lowlands. The moth is not unlike the pale tussock, although noticeably smaller, and its native habitat is oak woodland.

The caterpillars, which are covered with irritant hairs, rest by day in a large communal silken "nest", Coming out at night to feed on the oak foliage. When leaving the nest they move in a wedge-shaped procession from which habit they have been given their common name.

Throughout this hot spell (and well on into the autumn) many other migrants were noted, right across the county. The day-flying humming-bird hawk-moth, Macroglossum stellatarum, was recorded at Gt. Barton (CT), Ipswich (RSn) and (SG), Barrow (AP), Milden (CP), Westleton (HL). Ilketshall St. Lawrence (GK), and Monks Eleigh (AW) where three were seen together on a Caryopteris bush on September 19th. The larger, conventionally night-flying, convolvulus hawkmoth, Agrius convolvuli, was equally widely distributed with specimens being reported from Ipswich (AF), Kesgrave (RSt), Debenham (JR), Felixstowe (Mr. G.), Landguard (NO) and Haughley (WT) where a pair were seen in cop. The even larger death's head hawk-moth, Acherontia atropos, was reported from Woodbridge where a specimen was found behind security shutters at a shop on September 9th. A single female bedstraw hawk-moth came to light at Sicklesmere (SD) on June 29th, laid 193 eggs in captivity and was subsequently released on July 6th, still in good condition. (See Plates 3 and 4) The silver Y, Autographa gamma, was seen by most recorders, but not in quite the profusion of some other years. Another regulär and widespread migrant, the dark sword grass, Agrotis ipsilon, was well represented with records from Aldringham (RM), Barrow (AP), Felixstowe (JN), Landguard (NO), Minsmere (CA), and Purdis Heath (SN). Not quite so much in evidence was the great brocade, Eurois occulta, with reports from Nowton (RE) and

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Minsmere (CA) and (RK). Two other well represented migrants were the pyralids, Udea ferrugalis, and the rush veneer, Nomophila noctuella, both of which are with us in most years. Another migrant pyralid, Ancylosis oblitella, was recorded at Landguard (NO) on September 25th. This specimen was tentatively identified by Roger Kendrick and the identification confirmed by Mark Parsons (Natural History Museum). This is a species that was formerly a scarce immigrant to Britain but has been established on both sides of the Thames estuary since 1956. In 1976 there was an expansion in the ränge of this species but this is the first time it has been recorded in Suffolk.

Two other pyralids that are considered as resident in Breckland were recorded elsewhere in the county where they are most likely to be migrants.

Evergestis extimalis, which is associated with charlock and white mustard as larval foodplants in the Breck, was reported from Ipswich (SL) on July 27th and Landguard (NO) on July 2Ist and 30th and August Ist. Also recorded at the coast at Orford (AA) was Margaritia sticticalis, which was seen by day on lavender flowers in Quay Street. This comparatively scarce (until 1995) species also came to light at Minsmere (RK) on August 2nd. With larvae feeding on mugwort it is hard to understand why this species, which for a long time was a well known inhabitant of Breckland, is now of such uncertain status as a resident in this country.

Several other migrant species have been recorded as singletons - the anglestriped sallow, Enargia paleacea, (which is regarded as a migrant south of a line from the Bristol Channel to the Wash) at Monks Eleigh (AW); the silver barred, Deltote bankiana, (which is known as a resident in England only from the Cambridgeshire Fens of Chippenham and Wicken) at Minsmere (CA); the tawny wave, Scopula rubiginata, at Woodbridge (RK); the vestal, Rhodometra sacraria and the pearly underwing, Peridroma saucia at Nowton (RE); two specimens of the scarce bordered straw, Heliothis armigera, one of the Landguard (NO) and one in Felixstowe (JN) with the same number of the bordered straw, Heliothis peltigera, at Landguard (NO) and Stonham (JS).

On October 2Ist the tortrix Crocidosema plebejana was recorded at Landguard (NO) and the identification confirmed by Kevin Tuck (Natural History Museum). This is a widely distributed and common species in sub-tropical and warmer parts of the temperature regions. The earliest British record is from south Devon in 1900 where it is thought the species had been introduced. Since then it has been recorded progressively further east and north with specimens from east Kent and south Essex in 1982, Berkshire in 1983 and 1984, Cumberland in 1985 and north Wiltshire in 1990. This is the first record from Suffolk and thus another addition to the county list. Whilst a singleton is in all probability a migrant, subsequent records may indicate a more permanent population.

Following the report last year of a Single least carpet, Idaea vulpinaria stratosignaria, from Levington this species has occurred at two more sites in 1995. This moth, which is an inhabitant of hedgerows, gardens, scrub downland and chalk embankments was recorded from Landguard (NO), where three were noted between July 2Ist and 30th, and Aldringham (RM). Although these specimens were probably Wanderers from Essex or Kent or casual migrants, with more records from more sites a breeding population becomes more likely.

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The water ermine, Spilosoma urticae, is another species that was recorded in 1994, the first time since 1989 when it was noted at Aldeburgh, but unforunately the record was not received and confirmed in time for inclusion in the 1994 review. It was seen again in 1995 at the same Minsmere site (CA) which might indicate a population increase in the species. The water ermine is a moth of fens, marshes and water meadows, with the larvae feeding on various herbaceous wetland plants, and is very local in its occurrence. Although the moth has white wings and would not be mistaken for the normal, well spotted, form of the white ermine, Spilosoma lubricipeda, as it has just two small black discal spots on the forewing and sometimes a short row of black apical spots it can be confused with the immaculate form of the white ermine. Males, which are the ones that usually come to light, can be identified by the colour of the shaft of the antennae. The antenna of the white ermine have an all-round blackish shaft whereas that of the water ermine is white on the upper side and only black on the underside.

In recent years the orange moth, Angerona prunaria, has only been reported twice and then as singletons. The Situation changed quite dramatically in 1995 with this woodland/heathland species being reported from five sites across the county and in appreciable numbers at most of them. It occurred again at one of its previous haunts, Weston (NM), where three were noted: Wolves Wood (RK) where on July 8th 26 were recorded and five on July 25th (SL); Woodbridge (RK) where over a period of a week 18 came to light (eight being the most on any one night); Offton Middle Wood (SL) where it was described as "common" and Miller's Wood Bramford (SL). This very attractive moth is a species to look for in the Coming seasons. Another species that has made a recovery in the last few years is the marbled clover, Heliothis viriplaca. With fair numbers turning up at both Nowton (RE) and Sicklesmere (SD) it is obviously breeding in that part of the county.

The Kent black arches, Meganola albula, is a species that seems not to have been recorded in Suffolk until 1948, and since then it has been irregularly reported from several coastal (and one inland) sites. It was noted at Landguard (NO), Aldringham (RM) and Minsmere (CA). With the larvae feeding on raspberry and strawberry (and dewberry) and probably other members of the Rosaceae it seems likely that this species should be found at more sites for the next year or two at least. Another species that is only sporadically reported although supposedly "not rare along the coast" is the rosy wave, Scopula emutaria. It was recorded at Minsmere (CA) where it inhabits the edges of the coastal marshes. The feathered brindle Aporophyla australis pascuea, is a maritime species inhabiting sandhills, shingle beaches and sea-cliffs. Known chiefly, although intermittently, from the southern coasts of England, reports from Aldringham (RM) and Landguard (NO) confirm the continued presence of this species from the most northerly of its recorded locations. The much more widespread mainly coastal species, the feathered ranunculus, Eumichtis lichenea, continues to occur around the coasts and, of late, at one or two inland sites. The supposedly more widely distributed large ranunculus, Polymixis flavicincta, is surprisingly sparsely recorded in Suffolk. A singleton on October 8th at Landguard (NO) shows that it is still to be found in the county, but for a species that can be found in a ränge of habitats, on both calcareous and acid

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soils, with polphagous larvae it is a moth to look out for in the Coming years.

The fungus-feeding waved black, Parascotia fuliginaria, is missing from East Anglia on the distribution map for this species in volume 10 of 'The Moths and Butterflies of Great Britain and Ireland' (1983) - although mention is made of Suffolk in the text. It was last recorded in Suffolk from Walberswick in 1959 and in the last couple of years from near King's Lynn in Norfolk. A current record of this species from Landguard (NO) on July 29th may indicate a spread of this moth into the eastern counties. The fungi most favoured by the larvae are Coriolus versicolor, Hirschioporus abietina and Piptoporus betulinus but it can also be found on several other species associated with areas of fallen timber and as it seems the moth is not found far from the foodplant, investigation of such areas may show a wider distribution for this species.

Mathew's Wainscot, Mythimna favicolor, is one of the least common resident species of the genus. It occurs very locally in salt-marshes from southern Suffolk to East Kent, and again from West Sussex to western Hampshire with the occasional isolated inland record. It is unknown outside England. With five being recorded at Landguard (NO) between June 3rd and July 6th it is obviously still well established in the county and should be found at other suitable sites nearby. The larvae feed on common saltmarsh grass, Puccinellia maritima, where they can be found in May. Another wainscot, although of a totally different genus, the white-mantled wainscot, Archanara neurica, is known in Britain only from Suffolk marshes and then usually from around Walberswick and Minsmere. The record of this species, whose larvae feed internally in the stems of common reed, Phragmites australis, from Woodbridge (RK) is a little outside its usual territory and may represent another Station for this moth, or it could be a wind-blown "wanderer", time may teil.

On May 3Ist a footman moth came to light at Woodbridge (RK) and was identified as the orange footman, Eilema sororcula. This is a locally occurring moth of oak and beech woodland with the larvae feeding on various lichens growing on these trees. As the last record for this species was from the Dunwich Forest in 1963 a current report is most encouraging. The moth flies in late May and throughout June which is considerably earlier than any other footman. Thus it is unlikely that a specimen of this fairly distinctive moth was misidentified, but it would have positively confirmed the identification had either specimen or photograph been available.

Several other less common woodland moths have been reported from various sites during the last year. The blotched emerald, Comibaena bajularia, whose larvae feed on oak, was recorded from Sicklesmere (SD), Minsmere (CA), Wolves Wood (RK) and Purdis Heath (SN). The common lutestring, Ochropacha duplaris, which is not particularly widely recorded in Suffolk was noted at Minsmere (CA), Thornham (MH) and Purdis Heath (SN). With larvae feeding on birch oak, alder and occasionally hazel it must be more widely distributed than current records indicate. The poplar lutestring, Tethea or, which was recorded in Wolves Wood (RK), is more local in its appearance and tends to follow the distribution of aspen, Populus tremula, (although the larvae do sometimes feed on other species of Populus). Groton Wood (RK) was the site for the only record of the sloe carpet, Aleucis distinctata, in 1995. This moth flies in April and is a local species most usually found in south east England. It

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does not appear to be known from the north of Suffolk.

Both the mottled grey, Colostygia multistrigaria, and the yellow horned, Achlyaflavicornis, were recorded from Knettishall Heath (MB) on March 18th, and the fact that such species are not more widely reported from heathlands must be due to their early flight time when few recorders venture out. The reddish light arches, Apamea sublustris, which had not been reported in Suffolk since 1965 at Icklingham, was recorded at Elveden (RE) and away from the Breck at Landguard (NO) and Woodbridge (RK). Although quite well known from the Norfolk Brecklands in recent years these "new" Suffolk records, especially those from the coastal area where it has not been seen for many years, could indicate an upturn in the fortunes of this species which is mainly assoc'iated with the chalk and limestone districts of England and Wales. The grey carpet, Lithostege griseata, which is exclusive to the Breck distnct of Norfolk and Suffolk, was noted at Eriswell (SD) and Nowton (RE). This species can frequently be disturbed from its larval foodplant during the day. Several species of moths can be found by day and some are truly diurnal. Both the clouded buff, Diacrisia sannio, which was seen at Elveden (SD) and the Mother Shipton, Callistege mi, from West Stow (SD), are usually seen by day but it is only the male of the clouded buff that flies freely in sunshine. The female becomes active soon after dark, and again shortly before dawn. Day-flying species of moths are significantly under-recorded which may be due, in part, to over specialisation by field naturalists.

Another group of day flying moths, the clearwings, are also probably underrecorded, but here the reason may well be one of identification as these virtually scale-less species look more like hymenopterans than moths. The hĂśrnet moth, Sesia apiformis, is one that is noticed most years. In 1995 three fresh specimens were seen on a poplar tree at Nowton (RE). They had emerged from pupae between 7.00 and 7.30 am. This species was also recorded at Landguard (NO) where it has been seen for the last few years. Much less frequently observed is the yellow-legged clearwing, Synanthedon vespiformis, which was also recorded from Nowton (RE). This species is associated with oak stumps where the larvae have been feeding under the bark. Not all moths seen by day are expected and the red underwing, Catocala nupta, feeding on over-ripe plums in Rafe Eley's garden on the afternoon of September 14th was most certainly unexpected. To quote Rafe, 'The moth looked huge - gave me quite a turn".

Another large moth, which although comparatively common is infrequently recorded, is the old lady, Mormo maura. It is a nocturnal species and, although it comes readily to sugar, it rarely appears at light. It is more frequently spotted these days (when sugaring is not particularly populär) by being disturbed from its day-time resting place. One was recorded from Purdis Heath (SN) in 1995.

Although there are several moths mentioned above that have been more in evidence in 1995 than previous years there are equally as many that seem to be declining. In general terms many of the autumn species, particularly the sallows, chestnuts and some of the thorns, were almost non-existent in several sets of records. Species like the Chinese character, Cilix glaucata, clouded drab, Orthosia incerta, small quaker, Orthosia cruda, and common rustic Mesapamea secalis, are all less numerous than for the last few years. In spite of the really warm spell and the migrants which it brought many of the recorders

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reported an overall quiet season with probably more resident species showing a decline in numbers rather than an increase. Do please send any records of moths to either the county recorder, Arthur Watchman, Onchan, Back Lane, Monks Eleigh, Suffolk, IP7 7BA, or to the Suffolk Biological Records Centre, c/o The Museum, High Street, Ipswich IP1 3QH, as everything helps to determine the status of moths within the county.

Acknowledgements I am most grateful to Alasdair Aston (AA) for the time and effort he has put into searching the literature for previous records of those species that have been claimed as new county records in these notes and for his records of Suffolk sightings in 1995. I also thank all the recorders whose records and notes have helped to compiled this report: Charlotte Anderson (CA), Maggie Brooks (MB), Stan Dumican (SD), Jim Foster (JF), A. F. Fry (AF), Mr. Garnham (Mr. G.), Steve Goddard (SG), Roger Kendrick (RK), G. Knight (GK), H. Leggett (HL), Stuart Ling (SL), Rob Macklin (RM), Audrey Morgan (AM), Norman Muddeman (NM), Jon Nicholls (JN), Steve Noye (SN), Nigel Odin and Mike Marsh (NO), Caroline Peacock (CP), Janet Revett (JR), Reg Snook (RSn), R. Stobo (RSt), W. Talbot (WT). C. Thompson (CT) and in particular Rafe Eley (RE), Adrian Parr (AP) and Arthur Watchman (AW) whose additional comments on numbers and fluctuations have helped to give the picture of the overall status of moths in Suffolk at the present day.

M. R. Hall (MH), Hopefield, Norwich Road, Scole, Diss IP21 4DY.

White-point Moth, Mythimna albipuncta D. & S., in 1995 This year I was pleased to note a specimen of the White-point Moth, which had flown to light at Market Hill, Framlingham, on August Ist. The moth was in good condition and reminded me of evenings in the 1940s when I worked reedflowers in the now departed osier-beds to the west of Stowmarket.

The species is immigrant and had not been noted in Suffolk from its discovery at Hemley in 1902 until 1938 when C. Garrett-Jones found it at Iken.

From the 1940s onwards it was observed regularly but mainly in eastern localities: Foxhall, Martlesham, Bosmere, Belstead, Southwold, Walberswick, Aldeburgh, Staverton and Waldringfield. The last record I can find in the Transactions dates from Needham Market in 1968. There must, surely, have been occurrences in the interim?

Alasdair Aston

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Plate 3: Bedstraw Hawk-moth, Hyles galii (Rottemburg), a scarce migrant found at Sicklesmere, June 29th 1995 (p. 16).

Plate 4: Larva of Bedstraw Hawk-moth, raised in captivity from eggs laid by the adult shown above (p. 16).