Aculeate Hymenoptera Recorder’s Report 2020.

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ACULEATE HYMENOPTERA RECORDER’S REPORT 2020 ADRIAN KNOWLES

Chris Kirby-Lambert

Undoubtedly, the highlight of this year was a species new to Britain, discovered at a site in Suffolk. On 10 August, Christopher Kirby-Lambert was undertaking survey work at a brownfield site in vice-county East Suffolk (confidential location at present), when he saw and photographed a strikingly red specimen of a Sphecodes bee. This was subsequently identified as Sphecodes albilabris. It is a cleptoparasite, attacking the nests of the mining bee Colletes cunicularius. This is an interesting relationship, because the bulk of the population activity of the two species does not actually overlap. Males and females of this Sphecodes are active in July and August, with the newly mated females then building up their fat reserves, finding shelter and overwintering. They then emerge in March and seek out the nests of C. cunicularius, which is a spring-time species, generally active during April and May. The nests within which the Sphecodes lays her eggs then produce the next generation of Sphecodes in late summer once more. Colletes cunicularius is a scarce species in Suffolk, but one that is extending its range, so new populations of the cleptoparasite may well await discovery in coming years.

There have also been two species recorded in Suffolk for the first time. On 25 May, Stuart Read discovered a small colony of the bee Osmia aurulenta at Landguard Point, Felixstowe. It is one of several species of Hymenoptera that choose to form nests within empty snail shells. It has a slightly “Atlantic” distribution in Britain, being quite common along the English Channel from Kent to

Steven Falk

Sphecodes albilabris male, August 2020, Suffolk .

Osmia aurulenta

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Cornwall, the coasts of north Devon and Wales and a few records further up the Irish Sea coast to southern Scotland. There is a single spot on the national distribution map along the north Norfolk coast. Landguard Point therefore represents a very isolated population between Norfolk and Kent. Is it a recent colonist or has it been there all along, undetected?

A second new species for the county is the solitary mining bee Andrena bucephala.

Whilst this bee has been recorded quite widely along the south coast counties, the west Midlands and east Wales, there are precious few records for the east of England.

In May, Mark Ferris photographed a female at Denston in VC West Suffolk, with its identity verified by Stephen Boulton and Steven Falk via social media and email (see p. xx). Males of this species are often distinctive in that they can develop massively over-sized heads compared to their body size.

The lure of seeing Osmia aurulenta at Landguard was too much for me and whilst it took me two attempts to find it, during the first attempt and in the company of David Basham, I took a specimen of the potter wasp Odynerus melanocephalus. This is a species that has shown signs of moving northwards through Essex over the last 3-4 years, so its arrival in Suffolk was not entirely unexpected. The first known Suffolk record was made by Bex Cartwright in July 2018, at Flatford field centre in the south-east of the county.

It nests in the ground, often utilising quite clayey soils on level ground. As with other species of Odynerus, the females erect a small chimney of soil particles over the entrance to the nest tunnel, although this is dismantled when the nest is complete. To return the compliment, David Basham then caught another specimen of Odynerus melanocephalus on 3 July, while we were both visiting an area of farmland at Witnesham, north of Ipswich. This third record in three years adds strength to the suggestion that its population is expanding northwards – possibly another sign of global warming, although it is already known from more northerly latitudes in the Midlands and north Wales.

The following sections summarise some of the other interesting observations made this year.

Family Andrenidae Andrena alfkenella – nationally, this is a scarce bee, restricted to southern England and East Anglia. It is found in dry, often calcareous, grassland and in Suffolk is limited to a handful of sites around Breckland in the north-west. A female was found in the King’s Forest on 21 July, whilst undertaking survey work for the Forestry Commission along its newly created grassland corridors through the plantations.

Andrena fulvago was returned to the Suffolk list in 2012 after an absence of over 200 years, when I re-discovered it at Chantry Park, during a bioblitz event. A second record followed in 2014 at Kessingland, during another bioblitz event, organised by Africa Alive. Since then, there have been several records from the south-east of the

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county, including from my garden in Capel St Mary on 7 May 2020. On 23 May, Stuart Read claimed the first record for VC West Suffolk when he photographed a specimen in the King’s Forest, this being verified by Stephen Boulton.

Andrena proxima is listed on the UK Red Data List of threatened species, although it may now be more widespread than previously thought. In Suffolk it is proving to be quite widespread in the central zone of clayey soils that separate Breckland and the Sandlings. On 7 May, Hawk Honey recorded two different males from around Horham in the north of central Suffolk. I also recorded it twice this summer, from Mendlesham industrial estate and just to the north of there, in Stoke Ash churchyard. Churchyards seem to be good places to look for this bee, where females forage at flowers of Cow Parsley (and other umbellifers) that often proliferate in such locations.

Andrena wilkella is a widespread species nationally, but with rather few records in Suffolk. It is known from a few sites in Breckland and a scatter of records from the east coast Sandlings. To this we can now add Pipers Vale in Ipswich, where David Basham found two females on 30 May.

Bombus rupestris – this Nationally Scarce cuckoo-bumblebee was found at the Suffolk Flora Preservation Trust’s (SFPT) Fromus Reserve near Kelsale in east Suffolk. During 2020, SNS Recorders were invited by SFPT to record wildlife at this and their other nature reserve, Orchid Glade near Hasketon. During 2020 a record from 2019 was added to the national iRecord database, observed and photographed by Paul Kitchener at Shottisham Creek.

Steven Falk

Family Apidae Anthophora quadrimaculata – this bee is scarce nationally, with most records coming from south of the Thames in the far south-east of England and very few records in East Anglia. During June and July, David Basham recorded it several times within Ipswich, almost doubling the number of modern Suffolk records. It may nest in sandy soils or within soft masonry of walls.

Bombus rupestris

Xylocopa sp. – these large, striking solitary bees are becoming regular vagrants to the UK with occasional evidence that suggests the formation of probably short-lived nests. In September, Helen Scrivener posted on iRecord a photograph of what is undoubtedly a specimen of Xylocopa from Melton, near Woodbridge. There are several species found in mainland Europe but all those specifically determined in the UK have been X. violacea.

Family Bethylidae This family of wasps comprises only a few, very small and inconspicuous species that are rarely observed directly. Rather, they are generally encountered when sweeping

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vegetation with large nets or using suction samplers to extract insects from grassland vegetation. As such, all members of this family are highly under-recorded.

Bethylus fuscicornis – recorded twice: rough grassland on the edge of an industrial estate at Mendlesham in VC East Suffolk on 6 July; golf course rough grassland within the Center Parcs holiday village on 14 September.

Epyris niger – the second modern record for Suffolk came from the same Mendlesham site as above, on 24 August. The only other Suffolk record dates from 2014, when it was recorded in grassland at Red Lodge, near Mildenhall.

Family Chrysididae Wasps in the genus Chrysis are difficult to separate and for a long time even taxonomic experts differed in opinion as to how many species were actually involved at a European level. The realisation, partly through using DNA testing, that the UK might have three more such species was only likely to add to the confusion. However, one of them, Chrysis terminata, is quite easy to recognise with the key feature being the brow ridge that is divided into four distinct bumps. Hawk Honey caught two females at Lackford Lakes (10 May and 23 June) whilst I found a specimen at the SFPT’s Orchid Glade reserve, Hasketon, on 16 July.

Ectemnius rubicola – this was another interesting find from the SFPT Fromus reserve and, to my knowledge, the first record for VC East Suffolk. Most species of Ectemnius nest in galleries in dead wood, but E. rubicola habitually nests in hollow plant stems, such as Brambles and Common Reed. As such, nest site availability ought not be a limiting factor in its distribution. However, it may be on the edge of its ecological range in England, with most records coming south of the line connecting the Severn estuary and The Wash.

Lestiphorus bicinctus – there were, to my knowledge, only three modern records of this wasp from Suffolk, all in VC East Suffolk. However, on 18 August Hawk Honey found a female at the Lackford Lakes visitor centre, where it has seemingly drowned in a tray of water. This wasp is thought to nest in light sandy soils and so there is no reason why this species should not occur widely in Breckland. However, this Nationally Scarce species would be at the edge of its known range in the UK here, with most populations being found in the far south-east of England.

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Steven Falk

Family Crabronidae Cerceris quinquefasciata – this Species of Principal Importance in England (formerly referred to as “Priority” species) has been quite widely recorded across Suffolk in suitable habitat. However, my experience suggested that I was not coming across so many over the last few years. This summer, though, I recorded it widely and with ease from the King’s Forest, where Forestry Commission work is creating a network of broad grassland rides in order to benefit Breck grassland species.

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Steven Falk

Family Melittidae Melitta leporina is a scarce species in the UK, with its core range in the south-east, although there is also a good population centred on Breckland. In Suffolk, there is also a record from near Sproughton in 2001, from Colin Plant. On 25 June this year, David Basham caught a male at Witnesham, north of Ipswich. Then, on 28 June, Jo Southall found it within the Ravenswood development in Ipswich, confirmed by Stuart Roberts on iRecord.

Melitta tricincta – this solitary bee was, until this year, known from only four records, all in the north-west. This was added to by Stephen Boulton, who recorded a male from the King’s Forest on 8 August. Even more interesting, on 21 July Stuart Read encountered this species at Great Cornard, near Sudbury, the first record for south Suffolk.

Family Pompilidae Arachnospila spissa – whilst quite widely recorded in Breckland and more sparingly along the lighter soils of the coast, Hawk Honey’s capture of a female on 6 August at the Suffolk Wildlife Trust’s Knettishall Heath reserve is something of an outlier from the main north-west populations.

Family Sapygidae Sapyga quinquepunctata – this cleptoparasitic wasp has been widely recorded across southern Britain, so it is a surprise that it has been found so sparingly in Suffolk, with only about a dozen records from a handful of different localities. May’s coronavirus lockdown prompted me to do some recording in the small nature reserve in Capel St Mary and on 15 May I observed a male patrolling around a wooden pylon pole. Females lay their eggs within the nests of bees in the genus Osmia and these generally nest in galleries within standing dead wood, so a wooden pylon may look like a likely place to find a mate! In reality, this is unlikely since the preservatives within the pylon timber would prevent wood-boring beetles that are often the originators of such galleries.

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Steven Falk

Evagetes pectinipes – until 2007, this spider-hunting wasp was only known from a limited area in east Kent. Since then, it has spread northwards and westwards, with the first Suffolk records coming in 2016, when Ian Cheeseborough and Andy Jukes found it at Westleton and Wangford,respectively, both in VC East Suffolk. This summer, I caught a female from a hillside acid grassland at Union Farm, Blythburgh (not far from the Wangford location). More interestingly though, Hawk Honey caught a male on 4 May at Lackford Lakes. This may be the first record for VC West Suffolk.

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Family Vespidae Dolichovespula saxonica was first recorded in Britain in 1987, but has spread rapidly across southern Britain. However, it remains severely under-recorded in Suffolk, with only a small handful of records from Breckland and a single record from Corton in the far north-east (Paul Lee, in 1999). Most of the social wasps are probably underrecorded, not helped by their more aggressive behaviour when trying to handle them.

Adrian Knowles Jessups Cottage London Road Capel St Mary Suffolk IP9 2JR

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