Some East Suffolk Hover-Flies

SOME EAST SUFFOLK HOVER-FLIES

By W. S. GEORGE for entomology, I centred

restricted time my collecting on the Syrphidae or Hover-flies, hoping so to cover this limited field. But with 233 species listed as British, I have found this ta larger than expected, and so can comment on only a few specie I have found members of eight of the eleven sub-families.

The VOLUCELLINAE, large, strikingflies,whose larvae scavenge wasps' and bees' nests, are well represented. I have seen all five species in East Suffolk, most usually Volucella bomby Linn. (June to August), a variable species, each formofwhich mimics the bumble bee supporting its larva. But V. pellucen Linn, almost as common, in no way resembles its host, the commo wasp. With both these species in Fen Wood, Blythburgh, I took three males of V. inanis Linn, on August 2nd, 9th and 16th, This species, I think, is not previously recorded from Suffolk.

The larger migrantflyV. zonaria Poda. I saw at Easton Wo near Covehithe on July 16th, 1950, again the only Suffolk record I know. I have one V. inflata Fab. from Walpole3 on Tulv 1 1949.

The ERISTALINAE with their peculiar looped vein near the wing-tip, are noticeableflies.Most Eristalis species mimic the hive bee. E. tenax Linn, is common ; I oftenfindit in the centre of Haiesworth, and it shares my garden at Aldeburgh with E. arbustorum Linn, and E. nemorum Linn. For som unknown to me, all EristalisfliesI have seen in Fen Wood hav belonged to the species E. pertinax Scopoli., easily recognised by its orange front feet. E. pertinax also abounds on the road just north of Westleton. Neither locality is near many houses.

E. tenax is known to be associated with drains as a larva. E carius Linn, resembles a small bumble bee, and is sometimes s E. sepulchralis Linn. andÂŁ. aeneus Scopoli., I have also s are drab. MyiatropafloreaLinn, occurs in woods and fields also Helophilus species with their yellow-striped thorax. I take Merodon equestris Fab. (The Bulb Fly) whenever I s the Linden Road, to lessen the attacks on my Narcissi. This summer I took it on June Ist and 12th.

WITH

The EUMERINAE also attack bulbs. Eumerus strigatus Fal small drabfly,was in a garden at Walpole in August, 1951 and unfortunately, in mine this June Ist. Most frequent of the XYLOTINAE is Syritta pipiens Linn, a narrowflywith thick hind legs. This May it was the commonest Syrphid in my garden, and it remained frequent throughout the summer. Tropidia scita Harris and Xylota segnis Lin

EAST SUFFOLK HOVER-FLIES

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frequent in woodland, and on July 12th, 1956, I took the striking X. sylvarum Linn, in Fen Wood, and saw another there the next year on July 4th.

The SERICOMYIINAE are with us as Sericomyia silentis Harris, with its wasp-like stripes. It was in Fen Wood on Tulv 4th and 18th, 1957.

The CHEILOSIINAE, are less striking than most Syrphidae, though Ferdinanden cuprea Scopoli. at once attracted my attention at Haiesworth on August 13th, 1951 ;—I have not seen it since.

Chriosia illustrata Harris, a handsome fly, occurs from June to September, and other less conspicuous Chilosia species such as C. paganus Meig., C. impresso Loew. and C. antiqua Meig., I find also. Rhingia campestris Meig. is very common in May and June, and even in September, and Neoasciapodagrica Fab., hovers in the shade below branches and is difficult to see.

The CHRYSOTOXINAE I find sometimes, several species are the best mimics of the common wasp that I know, and so resemble each other, that I can definitely record only Chrysotoxum bicinctum Linn, which is darker, from Framlingham, August 7th, 1952.

The SYRPHINAE are friends of the gardener, because their larvae consume vast quantities of aphids. Syrphus balteatus Degeer. is very common in late summer, but I have never seen it before June 9th. Presumably aphidivorous larvae cannot thrive tili late Spring, when the greenfly suddenly multiply faster than byrphinae can. But soon the Hover-flies catch u p with the aphids, and keep the upper hand for the rest of the summer, a more satsfactory balance of nature for the gardener.

Syrphus corollae Fab. was extremely abundant this August, but not so in September, when S. vitripennis Meig. replaced it. Platychirus manicatus Meig. and Sphaerophoria scripta Linn, are common, also very many other members of this sub-family.

Xanthogramma pedissequum Harris I had at Haiesworth in midsummer, 1951, a specimen of Pyrophaena granditarsa Foster I have a female this August 28th, and of Paragus tibialis Fallen, a female this June 13th, irom Aldeburgh and Thorpeness respectively.

NOTE. Mr. George's discovery of Volucella inanis L. in Suffolk is great news indeed, and, with his discovery of Volucella zonaria, not only completes the genus for our county but brings the total ot Suffolk Syrphidae to 175 species out of a British total of 233. i his group has been quite extensively worked here for the last hundred years and so these additions are a sign of the intensive work being undertaken by Mr. George. Mr. Morley had V. wams only from the New Forest.

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