HYMENOPTERA REPORT 2022 ADRIAN KNOWLES
The exceptionally hot weather endured during the summer of 2022 has been a mixed blessing. What started out as a run of pleasantly warm, dry weather (highly conducive to aculeate activity) gradually became difficult conditions, as floral resources dried up and prey for predators became scarce. Too much of a good thing is bad for you…
One of the highlights of the year, back in March when there was no hint of what was to come, was the discovery of a species new to the county. This was the megachilid bee Osmia cornuta, which was only recorded in Britain for the first time in 2017. Even now, it is known from only a handful of sites in southern England. David Basham had suspicions that he had spotted females foraging at the flowers of a nearneighbour’s cherry tree (Ipswich) in 2021 but was unable to confirm it. However, in March 2022 he managed to secure a specimen, with the consent of the intrigued and interested neighbour! Although confirmation was not really needed, I went along to check out the small cherry tree and soon saw females myself. I then managed to see another female high in the canopy of a cherry tree in the nearby Alexandra Park. Although this is a very small sample, this prompts the suggestion that flowering cherries may well be fruitful places to search in the future (pun intended!).
Osmia cornuta female male
The following is a summary of other interesting discoveries made during the year. Recorders are David Basham (DB), Alan Cornish (AC), Hawk Honey (HH), Adrian Knowles (AK).
Bees
Andrenidae
Andrena alfkenella is a nationally scarce bee and in Suffolk is largely known from the Brecks. However, on 14 July, HH caught a female at Sotterley Park in the north-east of the county.
AC continues to record the mining bee Andrena florea from his garden in Reydon. For a while, this was the most northerly location for it in Britain, but Tim Strudwick has informed me that it has now reached Norwich in Norfolk. Further to this, a male was recorded on 3 June by HH at Lackford Lakes north of Bury St Edmunds, this being an
unusually westerly location for this bee in Suffolk. I am aware of only one other record of this bee for vice county West Suffolk.
AC also has Andrena tibialis nesting in his Reydon garden. This is a scarce Suffolk bee, although its stronghold is the Sandlings zone in the east of the county.
Andrena helvola is a widely distributed but very poorly recorded bee in Suffolk. On 9 May, AK recorded it from the cemetery adjacent to the churchyard in Bentley.
Apidae
The nomad bee Nomada zonata continues to spread across the county. AC recorded it from his garden on the coast at Reydon this summer. This is the first record for coastal Suffolk.
Colletidae
The mining bee Colletes cunicularius was recorded by DB from a series of flower-rich fields near Witnesham, to the north of Ipswich. The fields are being managed sympathetically for insects and wildlife in general and yielded several other important records, listed below. HH also caught a specimen at Lackford Lakes on 18 March.
Halictidae
The mining bee Lasioglossum puncticolle is largely restricted to south-east England, although occurring as thinly scattered records in East Anglia. DB recorded it at Westhorpe, north of Stowmarket, during a farmland survey supported by the Felix Cobbold Agricultural Trust and the Suffolk Naturalists’ Society, with the society funding equipment purchase. AK found it at Little Haugh Hall, near Norton, south of Ixworth whilst undertaking survey work for the owners of the hall and Suffolk Wildlife Trust.
The nationally rare Lasioglossum pauperatum is known from a handful of records scattered across Suffolk since 2017. On July 22, AK caught a female near the southern shore of Alton Water, south of Ipswich.
Megachilidae
Stelis phaeoptera has always been a rare be in Britain and recent trends suggest it is in decline. Its stronghold appears to be in the English/Welsh borders. I am aware of three modern Suffolk locations and AC has recorded it in his Reydon garden for a number of years. It is a cleptoparasite, laying its eggs within the nests of other bees, possibly other members of the family Megachilidae, such as Osmia spp.
Stelis punctulatissima is slightly more common, nationally, but is now known from only four modern Suffolk records, following AK’s discovery of it at Little Haugh Hall, Norton.
Melittidae
There are three species of Melitta in Suffolk, none of which is common. DB recorded both M. leporina and M. tricincta from farmland at Westhorpe The records of M. tricincta appear to be the first modern records for the vice county of East Suffolk. Although quite widespread in Norfolk, these are the most northerly records in Britain, although there are suggestions that M. tricincta is expanding its range, nationally.
Wasps Bethylidae
Bethylids and Dryinids are amongst the most under-recorded aculeate wasps in the country, on account of their small size and unobtrusive behaviour. On 2 August, AK caught a female Bethylus fuscicornis from Methersgate, south of Sutton Hoo. This may be only the 5th modern record for this species in Suffolk.
Chrysididae
On 10 July, AC photographed a small chrysid wasp on Bramble leaves in his Reydon garden. This was subsequently identified as a female Cleptes semiauratus. This is only the second county record of which I am aware, following Steven Falk’s capture of a specimen at Center Parcs in 1997. Nationally, it is a widespread but scarce and declining wasp.
Chrysis terminata has only recently been appreciated as a British species, with collection specimens coming to light, having previously been misidentified as other species within the difficult Chrysis ignita aggregate. AK, HH and DB caught specimens during a visit to Sotterley Park on 14 August and AK also encountered it on two occasions at Little Haugh Hall, Norton.
Pseudomalus auratus is quite widespread across southern Britain but is known from only a handful of Suffolk sites. On 5 August, AK took a specimen from the holiday village at Elveden, whilst carrying out survey work on behalf of Center Parcs.
Pseudomalus auratus found in Ipswich, visiting wild flowers on the Spring Road allotments, 16 June 2016, identified by Alexander Berg. This species preys on cabronid wasps that nest in cavities and prey on aphids.
Crabronidae
The digger wasp Ectemnius rubicola is quite widespread in central and southern England but has not often been recorded in Suffolk. On 21 May, HH caught a male in the Abbey Gardens, Bury St Edmunds.
Gorytes quadrifasciatus is a scarce species in Suffolk, inexplicably so given its widespread occurrence across the southern half of Britain. AC recorded it in his Reydon garden.
Miscophus bicolor was discovered new to Britain in 2003 at Maidscross Hill near Lakenheath and has been recorded there regularly since. It has now been found by HH in several locations in north Suffolk, including Wortham Ling (in 2021), Lackford Lakes in 2022 and Wenhaston in 2022. Tim Strudwick reports that it has also now been found in Norfolk – just – with a capture near the Thetford power station site this year.
The small digger wasp Rhopalum coarctatum has been widely recorded across southern Britain but there remain few Suffolk records, particularly in the last 20 years. DB found it in June, at Witnesham.
Eumenidae
The potter/mason wasp Gymnomerus laevipes is a very rare species in Suffolk. Until this summer, the only record of which I am aware is AK’s discovery at Landseer Park in 2019. DB recorded it from Witnesham in 2022.
The potter/mason wasp Odynerus melanocephalus has been recorded by DB several times in recent years from Witnesham and it continues to be active in the area in 2022. The only other modern record is from Landguard Common (AK). It is possible that the range of this wasp is expanding northwards, with recent records also from north Essex, having previously exclusively been a species restricted to the south of the county.
Microdynerus exilis is one of the smaller members of this family and it is a rare species in Suffolk. It is known from only a handful of well scattered localities, but AC continues to record it in his Reydon garden.
Tiphiidae
The wasp Tiphia minuta is a cleptoparasite, typically laying its eggs within the nest cell of developing dung beetle larvae. Although reasonably widespread across the southern half of Britain, it seems to be curiously scarce across East Anglia. It was recorded by DB at Witnesham.
Vespidae
The social wasp species (Vespula, Vespa and Dolichovespula) are probably all very under-recorded in the county, partly due to their aggressive nature when netted for closer inspection. The ‘Saxon Wasp’ Dolichovespula saxonica was not recorded in Britain until 1987 but is now widespread across much of Britain. However, there are only just over a dozen records for Suffolk, with HH finding it at Sotterley Park on 14 July and AK catching a male from Methersgate near Sutton Hoo on 2 August.