NOTES AND COMMENTS ON SOME SUFFOLK MOTHS IN 1991 M . R . HALL
In spite of a comparatively late start to the season, following yet another spring when nights were cold, and what seemed an extraordinarily early close in the autumn, moths recorded in Suffolk in 1991 have included a goodly number of rare, exciting and unusual species. A good deal has been added to our knowledge of the present-day status of several of the County's less common moths. As more records are received from an increasing band of recorders, the cyclical pattern of occurrence for many moths, both common and less common, becomes more obvious. Several species continued the apparent rise in both numbers and distribution that had been indicated in the preceeding year or two. Among such species are the golden plusia, Polychrysia moneta Hb., brick, Agrochola circellaris Hufn., bird's wing, Dypterygia scabriuscula Linn., garden dart, Euxoa nigricans Linn., treble bar, Aplocera plagiataplagiata Linn, and probably to a lesser extent the treble brown spot, Idaea trigeminata Haw., all of which were much less obvious four or five years ago. The treble brown spot is a species that has been steadily increasing in the last few years, as is the golden plusia which is a garden species with the larvae feeding on Monkshood and cultivated species of Delphinium. As would be expected if such cyclical changes are the norm, these increasing species are balanced by others that seem to be declining at the present time. In this group we are finding the large nutmeg, Apamea anceps D. & S., white ermine, Spilosoma lubricipeda Linn., and the dotted rustic, Rhyacia simulans Hufn., which had a really noticeable surge in 1986/87 but has been more-or-less absent from records since. It was recorded from Barrow (AP) in 1991, as was the fern, Horisme tersata D. & S. This is a species with a very specific larval foodplant, Travellers Joy, and it is almost certainly much more widespread in the chalky parts of the county than present-day records would indicate. Another widespread species, the maple prominent, Ptilodontella cucullina D. & S., has generally occurred at low densities and never been regarded as a 'common moth'. In 1991 there have been many more records than usual, from right across the county, and a similar increase in records has also been noted in Norfolk. There were also many records of migrants received in 1991 - the humming-bird hawk-moth, Macroglossum stellatarum Linn, was reported from many places (with one individual recorded for several days at Aldeburgh (FS)) as was the convolvulus hawk-moth, Agrius convolvuli Linn, (with the larva being noticed at Southwold (JW)). Another record of hawk-moth larvae was received from Ixworth (JC) where the very distintive elephant hawk-moth caterpillars on Fuchsias caused comment. Vine's rustic, Hoplodrina ambigua D. & S., was noted by many recorders across the county (AW, MH, RSL, NO, AP), and although it is regarded as a resident species
Trans. Suffolk Nat. Soc. 28 (1992)