THE GIANT LACEWING OSMYLUS FULVICEPHALUS SCOPOLI (NEUROPTERA) NEW TO SUFFOLK – a very belated record

RUNNING HEAD

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THE GIANT LACEWING OSMYLUS FULVICEPHALUS SCOPOLI (NEUROPTERA) NEW TO SUFFOLK – a very belated record DAVID R. NASH Osmylus fulvicephalus (Scop.) is easily the largest British neuropterid and its size (wingspan 50 mm) can best be appreciated if it is compared with the wellknown and common, golden-eyed, green lacewing Chrysoperla carnea (S.) agg. (wingspan 30 mm).

Osmylus fulvicephalus

Chrysoperla carnea

It is the only member of the genus found in this country and, as might be surmised from its appearance, it is closely related to the ant lion Myrmeleon formicarius L. (Myrmeleontidae) recently confirmed as a British species breeding in the county at Westleton. Osmylus occurs by streams and rivers, especially those passing through woodland, and its carnivorous larvae develop in moss at the water’s edge. Adults appear to be crepuscular and are most frequently encountered flying low over the water in May and June, although the flight period extends to early August. Unlike many other Neuroptera, it seems not to occur in light traps. Elliot (1996) provides a very useful review of its life history and ecology including details of the highly unusual courtship in which the males are the more passive sex and have eversible scent-glands to attract the females i.e. a reversal of the situation appertaining in, for example, many moths where it is the females who release pheromones to attract males.

It was not until a few years ago whilst browsing the species’ accounts in Colin Plant’s “Atlas of the lacewings and allied insects” (1994) that I realised that Osmylus had not been recorded from Suffolk. His map shows Osmylus to be widely distributed throughout Wales and the Welsh borders and in southern England south of a line from London to Bristol. There are two East Anglian records, but neither is from Suffolk.

Trans. Suffolk Nat. Soc. 45 (2009)

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Suffolk Natural History, Vol. 45

On a sunny day in May1961, I was wading in the River Fynn a few metres upstream from the road bridge at Tuddenham St. Martin (TM193485) and collecting insects from riverside vegetation on the eastern bank. Sweeping a small hawthorn overhanging the river and the marginal vegetation beneath it, I disturbed a pair of Osmylus (possibly more). This accords with Plant’s (op. cit.) comment that the species can be found during the day under bridges or overhanging trees which provide shaded conditions. Fortunately, I collected and set two voucher specimens and these were presented with other insects collected in my teenage years –Lepidoptera, Hymenoptera etc. – to Ipswich Museum in the late 1970s; my small collection of Suffolk Diptera went to Manchester University Museum.

Plant (op. cit.) suggests that “This large insect may be far more widespread than suggested by the map [and] overlooked in areas where it is thought not to occur”.

I concur with this opinion and feel certain Osmylus will be found elsewhere in the county. I would be very interested to receive photos (or specimens) from members who think they have found this interesting addition to our local fauna. I have not attempted to confirm the continued presence of the species at Tuddenham but I see no reason why it should not still be found there. It is worth noting in passing that the River Fynn downstream of Tuddenham St Martin below Rosemary Bridge is also the only known Suffolk site for the Nationally Notable dryopid beetle Pomatinus (previously Helichus) substriatus (Müller) which may be found clinging to the underside of floating logs and under stones in fast flowing streams and rivers. This I also found in 1961, but I could not re-find it there a decade later (Nash, 1972).

Acknowledgements I thank: Colin Plant and Adrian Chalkley for confirming that they still have no other Suffolk records of Osmylus and the latter also for a scan of part of Elliot’s key; Dan Sanford for locating and photographing my specimen.

References Elliot, J. M. (1996). British Freshwater Megaloptera and Neuroptera. A key with ecological notes. Scientific Publication No. 54. Ambleside, Freshwater Biological Association.

Nash, D. R. (1972). Four species of coleoptera probably new to the Suffolk county list. Trans. Suff. Nat. Soc. 16 (part 2): 211–214.

Plant, C. W. (1994). Provisional atlas of the lacewings and allied insects (Neuroptera, Megaloptera, Raphidioptera and Mecoptera) of Britain and Ireland, edited for the Biological Records Centre by P. T. Harding, B. C. Eversham and H. R. Arnold. Huntingdon, Biological Records Centre.

David Ridley Nash 3 Church Lane, Brantham CO11 1PU

Trans. Suffolk Nat. Soc. 45 (2009)