Semiothisa brunneata, a Scots Moth New to Suffolk

TRANSACTIONS. SEMIOTHISA BRUNNEATA, A SCOTS MOTH NEW TO SUFFOLK. BY

CANON A .

P . WALLER,

M.A.,

MOTU

RECORDER.

S I N C E the Suffolk Naturalists' Society came into being during 1929, and has continued to grow and develope not only in n u m b e r s but in the keenness and enthusiasm of its field-workers and observers, many notable additions have been made to the existing List of the county Lepidoptera. N o n e is perhaps more remarkable and unexpected than the capture, u p o n two separate occasions this year, of Semiothisa brunneata, T h u n b . , the Rannoch Geometer.

T h e first, a perfect male, was netted while Aying about two feet from the ground, in but not actually to light, just inside Barking W o o d at 11 p.m. during gentle rain on the evening of 14 J u n e by M M . John and Geoffrey Burton of N e e d h a m Market. T h e very next day, a miserable one of nearlv perpetual drizzle b u t warm and airless, M r . Samuel Beaufoy happened to be collecting in Bentley W o o d s and, about 3 p.m., flushed a Geometer f r o m Bracken ; this was in the midst of the wood, roughly half way between the north entrance and the T o a d - s p a w n Pond near the L o n d o n railway-line. Having secured the Insect, which M r .

Beaufoy supposed, casually in the field, to be Euchaeca obliterata, H f n . , as such it was set. However, when taken off the board a few days later, our H o n . Secretary found it to be a rather worn male of S. brunneata : it may be mentioned that both localities are in the south-east of the County, just nine miles a p a r t ; and that f u r t h e r efforts by the three captors, as well as other M e m b e r s on 23rd, were abortive.

H o w did they get here : had they settled in some motor travelling from the north, or taken an unbooked passage on the railway ?

Neither hypothesis is at all probable, for the Barking locality is some two miles f r o m the rail and Bentley an appreciable distance ;; though M r . Burton suggests their pupa; may have been thus conveyed in heather, often used as packing in war-stores' trucks.

According to Mevrick the l a n ae feed, not only on Vaccinium, but also on Firnis sylvestris ; and large n u m b e r s of Scots Pines have been imported to Suffolk by Government, possibly from Scotland.* However, here again both localities are many miles. *The fact that this species' pupa State often lasts three or.. four years may have some bearing upon the question.—ED.

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SEMIOTHISA BRUNNE ATA

from any such plantations; and Barking boasts no Coniferae whatever. I think \ve should postulate as more probable that some favourable atmospheric current has wafted these stragglers to Suffolk ; and hope other, equally welcome strangers may invade our County. Interest now centres on observing if they will stay.

S. (Itama) brunneata was unknown among Donovan's 336 British moths in 1792, and to Samouelle in 1819. T h e first British specimens were detected " amongst pine-trees in Black-wood near the shores of Loch Rannoch on 14th July " by J. C. Dale Esq., and John Curtis, who described them as his new Speranza sylvaria (BE. 1828, fol. 225). It is recorded from only Rannoch, feeding on Bilberry, in 1859 (Stainton), where ' Halia ' brunneata is still extremely common ; indeed ' Thamnonoma ' brunneata is abundant throughout the Highlands of Scotland (Entom. 1918, 65 & 264).

Until quite recently the distribution of this ' Fidonia pinetaria,' Hb., has been regarded as alpine and boreal all over Europe (Ent. Ann. 1873, 78) : the imagines fly in sunshine on Scots heaths only, during June and July ; their eggs are laid upon Vaccinium myrtilus, L., where they remain from July to March, and upon which alone the larvae subsist through the next two months (Newman 1871, Merrin 1875). Gradually it, or its observers, spread from Perth to Ross ; but not tili 1920 was there any suspicion of its presence in eastern England : then four males were recorded from Staffordshire ; a specimen reported as beaten from Sallow at Horning in the Norfolk Broads ; two captured by our late Member, Prebendary A. P. Wickham, at Wicken light in Cambs on 16-19 June that yeär ; and the southernmost example has been a solitaire, also at light six days later at Bishops Stortford College in Herts (Entom. 1920, 188, 211, 236 & 2 6 3 ; Trans. Herts. N H . Soc. 1937, 209). I know of none in these three counties later. No Bilberry exists throughout our County, though Schollera occycoccus, Roth., used to grow sparingly on Beccles Common.

Owing largely to the keen and methodical work of one of our original Members, the late Bishop Whittingham, a great manv species of Micro-lepidoptera were added to our County List, as reference to the excellent S N S . " Memoirs i." will show ; and, thanks to the indefatigable efforts and enthusiasm of many present Members, each year shows most satisfactory progress in this department. T h e reason is that this large group of small, and some of them very obscure, Insects has not been so well worked as the Macro-lepidoptera. Stalwarts of the last Century, enumerated at M e m . page 7, centred their attention mainly on the latter without specislizing on the former. But so well did they do their work that any addition nowadays made to the Macros. must be regarded as a cistinct achievement. However, it is just the ever-present possibility of taking something new and stränge that gives zest to researches into their economy.

GYNANDROMORPHIC ARGYNNIS A D I P P E , BLYTHBURGH W O O D , J U L Y

1946.

L.

SEMIOTHISA

BRUNNEATA

3

Mr. E. W . Platten startled the whole Society, some eight years ago, by announcing his discovery of Ptilophora plumigera, Esp. (Proc. 1938, p. xlvi) in our County : but the present captures of S. brunneata are perhaps still more amazing, adequately expressed bv nothing so apt as the pure Suffolk " T h a t be a masterpiece : I be wholly stammed " ! Indeed, we are surprised that this essentially northern Insect has been found within our boundaries ; and Members may well congratulate the assiduous discoverers of this 1521st species of Suffolk Lepidoptera.

T H E DIPTERA OF (Cont. :

Trans,

v,

SUFFOLK. 183.)

F A M I L Y iii: T H A U M A L E I D / E .

Thaumalea testacea, Ruthe.—One $ flew on to motor car in Thelnetham Fen at 3 p.m. 25 June 1944, giving us 1 of the 3 British species of this family.

F A M I L Y iv : A N I S O P O D I D / E . • Subfamily t r i c h o c e r i n / e .

Trichocera maculipennis, Mg.—Rare & found but singly : swept from reeds by Gipping at Ipswich on hot day 17 iii 1895 ; sitting on ceüing of Monks Soham (MS.) hall at midnight, after hot day 16 ii 1945.

T. annulata, Mg.—Probably quite general and not infrequent ; earliest of Winter Gnats : at moth-light in Barking Wood 14 xi ; Aying in Brandeston marsh 30 x ; a dozen dancing together in light N. air 6 feet over lavvn at 5.30 before dusk 28 ix, and about 4 p.m. on windows in mid-x, MS. ; on wall near sea in Southwold town 29 ix 1913 ; Ilalesworth (Hocken).

T. regelationis, L.—Profuse everywhere, 4 x-13 iv : Ipswich in 1895 ; Barking Wood at light 4 xi & dancing 5 ft. high in unusually dense & numerous cloud an hour before dusk 4.30 in warm light W. air 27 x ; MS. abundant at light, on windows & on 7 iii many pairs kept dropping to 6 ft. and then flving off in coitufrom large mass (?500 specimens) of dancing 12 ft. over gravel drive, with no air & temp. 50^° at early dusk 6 p.m., still several dancing there at 4 p.m. on 24 iii, but onlv 3-4 (? nearly over) ditto at 6 ft. at 6 p.m. 2 iv ; Blythbro Wood ; [in cop. on Oak-stool in Aldeby Wood, Norfolk, after dark 8 p.m. 3 iv 1933].

T. major, Edw.—Apparently scarce : Barking Wood, several at light 4 xi 45 ; Brandeston, beaten from Pine 3 p.m. 20 x 43 ; one at MS. light 10 p.m. 26 iv 1946.