Notes and comments on some Suffolk moths in 1989

NOTES AND COMMENTS ON SOME SUFFOLK

MOTHS

IN 1989 M . R . HALL a n d A . WATCHMAN

With the recording of an angle shades, Phlogophora meticulosa Linn., at Monks Eleigh on the 7th January (AW), and a fine, mild spell of weather at the beginning of March, the possibility of a lgood moth year' seemed in prospect. Unfortunately, despite the many gloriously sunny days throughout the summer, this was not to be. Many days were bright, warm, and cloudless, but these same clear conditions continued through most of the nights as well. This caused the temperatures to plummet, as low as minus 3°C at Lopham at 11.30 pm. on the 6th May and falling to 6°C on many nights in June, and the moths remained in seclusion.

However, the early fine spell produced several March records of the yellow horned, Achlya flavicornis Linn., from the King's Forest (RE), Thornham and Hopton (MH). The caterpillars of this moth feed on birch leaves, hiding between spun leaves, and it is only because few entomologists venture out during its flight period that current records are so sparse. Flying at the same time of year, but for a much shorter period, is the small brindled beauty, Apocheima hispidaria D. & S. This is an inhabitant of woodland and parkland, being associated with oak and sometimes hazel, and was recorded in the woods at Thornham (MH) on the 8th March. Both these attractive species are almost certainly relatively widespread throughout Suffolk and early field trips in many parts of the county should result in the records reflecting their true distribution.

During the same warm spell, on the lOth March, the lead-coloured drab, Orthosiapopuleti Fabr., came to light at Monks Eleigh (AW). This moth is widespread, and locally common, but its similarity to the much more common clouded drab, Orthosia incerta Hufn., has probably meant that it is not always recognised. The two species can be distinguished by differences in the hindwing, and the lead-coloured drab is associated with aspen. A species new to Monks Eleigh (AW) was the pine beauty, Panolis flammea D. & S., which was recorded during the same spell of weather. These caterpillars feed on various species of pine and it is occasionally a serious pest in conifer plantations in northern Scotland. Another early season moth that is most frequently found in Suffolk on the Breck heaths is the mottled grey, Colostygia multistrigaria Haw., and this was again recorded from the King's Forest (RE).

Throughout the year several breckland heath moths were recorded from the King's Forest (RE), which, for some, is one of their few remaining refuges in Suffolk. The grey carpet, Lithostegegriseata D. & S., is very local, the Breck district of Norfolk and Suffolk being the only area in Britain where it is to be found. Today it is not as widespread as it once was, so the above record is particularly encouraging. The larvae feed on the seed pods of flixweed (Descurainia sophia) and also treacle mustard (Erysimum cheiranthoides). The royal mantle, Catarhoe cuculata Hufn., which is another Trans. Suffolk Nat. Soc. 26 (1990)

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breckland moth reported from King's Forest, is more widespread nationally, preferring localities on chalk or limestone. Similarly the yellow belle, Aspitates ochrearia Rossi, (King's Forest - R E ) is found in breckland as its only major inland venue, being more commonly associated with sandhills, shingle beaches, the edges of salt marshes and other coastal sites. The larvae feed on wild carrot (Daucus carota), buck's-horn plantain (Plantago coronopus) and other low plants, whilst those of the royal mantle are to be found on both hedge and lady's bedstraw (Galium mollugo and G. verum). The netted pug, Eupithecia venosata Fabr., which again is associated with chalk downland and coastal cliffs, was also recorded at the same venue (RE).

A species of deciduous woodland, the square-spotted clay, Xestia rhomboidea Esp., was recorded from King's Forest ( R E ) as were the clay triple-lines, Cyclophora linearia Hb., and the cream-spot tiger, Arctia villica britannica O b . Although widespread and locally common in beech woods throughout southern England, the clay triple-lines is infrequently recorded in Suffolk, Hollesley Common being another of the few places where it is regularly reported. Similarly the cream-spot tiger is also known from Hollesley and the King's Forest as its two notable sites in the county. The purple-bordered gold, Idaea muricata H u f n . , was reported from Hollesley in 1989 (RSL) and this is another species found on the damper heathlands.

Hollesley (RSL) was also the place from which one of our rarer migrants was reported, the scarce bordered straw, Heliothis armigera Hb. Although almost an annual visitor it is always a scarce moth in Britain. The same site (RSL) was also the venue for a record of another erratic migrant, the white-speck, Mythimna unipuncta Haw., which is more usually found in southern Britain.

At one of the Society's moth evenings, at Aldeburgh (AW) on the 23rd June, another species more usually found today in southeast England was recorded. This was the water ermine, Spilosoma urticae Esp., whose larvae feed on various marsh plants including mint (Mentha spp.), yellow loosestrife (Lysimachia vulgaris) and yellow iris (Iris pseudacorus). This species has pure white wings and thorax and lacks the distinct discal spot on the hindwing which is present on even the most immaculate forms of the white ermine, S. lubricipeda Linn., (Skinner, 1984). It is essential that all possible water ermines are carefully examined for this discal spot as it is sometimes reported in error.

Another species that is also overlooked because of its similarity to a more common relative was recorded at another of the Society's moth evenings, this time at Knettishall Heath (MH) on the 15th July. The Single specimen of the piain wave, Idaea straminata Borkh., was distinguished from the many, and varied, individuals of the riband wave, I. aversata Linn., by Gerry Haggett, to whom we are grateful for this addition to the site list.

The third of the Society's moth evenings was on the 19th August at Wortham Ling (MH) where the number, and variety, of the white-line dart, Euxoa tritici Linn., was most interesting. Equally of interest was the fact that on that night the true lover's knot, Lycophotia porphyrea D. & S., was not recorded, and yet only four nights later, on the 23rd of August - at exactly the same site, and with virtually the same conditions-it was (MH). This helps to

Trans. Suffolk Nat. Soc. 26 (1990)

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Suffolk Natural History, Vol. 26

show how records from one site, on a single occasion, can be incomplete even for the common species known to be on the wing at the time of recording.

It is often when trapping is carried out at one site on a regulär basis that unusual species are seen. The scarce tissue, Rheumaptera cervinalis Scop., recorded on two days in May at Monks Eleigh (AW) is a species that has recently come in to that site. Many such records come from garden traps, and two from the north of the county are of interest. In Thrandeston (PW) the august thorn, Ennomos quercinaria Hufn., was recorded at a garden trap and the identification later confirmed by Rafe Eley. This species is superficially very similar to its more common relative the September thorn, Ennomos erosaria D. & S., and may be confused with it. Somewhat paradoxically, it is the September thorn that is on the wing first, being seen in August and even late July, whereas the August thorn is most usually recorded in September.

At the same site a single gold spot, Plusia festucae Linn., was recorded on the 8th of August. This is a species associated with fenland, and although reported widely in the 1950's and 1960's has been much less in evidence than Lempke's gold spot, Plusia putnami gracilis Lempke, from such haunts in recent years. Another gold spot was noted at Monks Eleigh (AW) on the lOth August. The record of a single Ptycholomoides aeriferanus H.-S. from Thornham (MH) is another example of the unusual being found through very regulär trapping. This small, readily identified, Tortrix shows very little Variation in markings and was first recorded in Britain in 1951 near Ashford in Kent (Bradley, Tremewan & Smith, 1973). It has subsequently been recorded from a number of scattered localities, including Elveden, and Harling Forest in Norfolk. It has been recorded well away from the larval foodplant, larch, and is apparently migratory. Almost certainly this species will be found elsewhere in Suffolk.

Throughout the year it was evident that several species were less in evidence than previously. Particularly noticeable was the decline in both the dark arches, Apamea monoglypha Hufn., and the light arches, A. lithoxylea D. & S. The sighting of a single brick, Agrochola circellaris Hufn., on the 3rd October at Monks Eleigh (AW) occasioned comment as this once comparatively common, elm-feeding, moth is now seen much less frequently.

Migrants were not greatly in evidence in 1989. In addition to those mentioned earlier, the humming-bird hawk-moth, Macroglossum stellatarum Linn., was reported from Minsmere (RM) Thrandeston (PW) and Felixstowe (SD), but no doubt occurred elsewhere. Also the dark swordgrass, Agrotis ipsilon Hufn., was noted at several places throughout Suffolk.

Records of these, or other migrants, are always appreciated, as are any sightings of moths in the county. Many species fly by day and are frequently encountered on 'non-mothing' field trips. Do send any observations to Arthur Watchman, or the Suffolk Biological Records Centre, c/o The Museum, High Street, Ipswich, IP1 3QH. Acknowledgements We would like to thank those recorders whose records have helped to make Trans. Suff olk Nat. Soc. 26 (1990)

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this report: Sheila Dolman (SD); Rafe Eley (RE); Rob Macklin (RM); Rob St. Leger (RSL); Peter Wanstall (PW); the other recorders whose Information has not been included and yet is equally valuable; and those members of the Suffolk Moth Group who have braved many 'cool' evenings in the Company of one or other of the authors.

References The moth nomenclature used in this article follows Bradley, J. D. and Fietcher, D . S. (1979). A Recorders Log Book of British Butlerflies and Moths. Curwen.

Bradley, J. D., Tremewan, W. G. & Smith, A. (1973). British Tortricoid Moths, Vol. 1, Cochylidae and Tortricidae: Tortricinae. London: The Ray Society.

Skinner, B. (1984). Colour Identification Guide to the Moths of the British Isles. Middlesex: Viking.

M. R . H a l l ( M H ) , Hopefield, Norwich Road, Scole, Diss, IP21 4DY.

A. Watchman (AW), Onchan, Back Lane, Monks Eleigh, Suffolk, IP7 7BA.

Pike A local naturalist told me that one day while he was watching swallows skimming over the River Brett at Hadleigh he suddenly saw a pike jump and catch a bird. I have often observed pike lurking near the surface of rivers, probably waiting for ducklings and other tasty water birds.

Until the general supply of a piped water system in recent years many cottagers without wells or pumps depended upon a garden pond for water. I have been told that often a pike would be kept in the pond which would keep the water cleaner and free from rats and various other harmful animals. It was considered a tragedy when the pike died and another fish had to be obtained.

Francis Simpson

Trans. Suffolk Nat. Soc. 26 (1990)