Description and notes A medium-sized, all black, scantily-haired bee with dirty-yellow scopae on the hind legs of the female. In dull weather males are often found curled up in the flowers of yellow- flowered Asteraceae, especially hawkweeds.They may stay shut inside the closed flower overnight.
Status (in Britain only) This species is not regarded as being of conservation concern and is not listed in Shirt (1987) or Falk (1991)
Habitat Associated with short- to medium-height grasslands over sandy or sandy-clay soils. It is often particularly frequent on coastal grasslands.
Flight period Univoltine, June to August.
Pollen collected Oliogolectic on the pollen of yellow-flowered Asteraceae.
Nesting biology Nests singly in the ground in open situations, although there are reports of females sharing burrows (G R Else in prep.), particularly where there is hard-packed, bare ground, such as along footpaths. Unusually, the nest entrances do not have mounds of excavated soil around them.
Found throughout much of Britain, though more often seen in southern England. Of special note are the Scottish records; also, the limited distribution of the species in Ireland, which may not be entirely a result of under-recording in that country.
Status (in Britain only) This species is not regarded as being threatened.
Habitat This wasp inhabits heathland, dunes and other coastal areas.
Flight period June-September.
Prey collected Various Lepidoptera larvae; rarely sawfly larvae (Richards, 1980).
Nesting biology A detailed study of the behaviour and ecology of marked A. sabulosa females has been made at a Breckland heathland site (Field, 1992). Nests usually occur at relatively low densities. Normally, a female digs a short burrow, ending in a horizontal cell, in bare or sparsely vegetated sand. Later, she temporarily closes the nest entrance using sand and tiny stones, then hunts for lepidopteran caterpillars in vegetation. About half of all cells are provisioned with just one large caterpillar, which is carried back on foot as it is sometimes more than ten times as heavy as the wasp. Other cells are provisioned with two to five smaller caterpillars (see Olberg, 1959). An egg is laid on the first caterpillar provisioned and rarely hatches before permanent closure of the nest burrow. After the last caterpillar has been interred the wasp permanently closes the burrow with a much deeper plug of sand, and camouflages the entrance with debris so that it is invisible to the human eye. All nests are unicellular. The whole nesting cycle, from searching for a digging site to closing the nest permanently after provisioning, takes an average of eight to ten hours of activity. Marked females each dug and provisioned up to ten nests during a summer.
Parasites One of the most interesting aspects of this species’ behaviour is that almost all females, as well as digging their own burrows and hunting for prey, parasitise the freshly provisioned nests of other A. sabulosa. When a female detects a conspecific’s nest she digs through the closure plug and enters. If the nest is empty, she quickly comes out and re-closes it; but if it contains prey, she either steals one of the prey items, or eats the host’s egg, replacing it with her own (brood parasitism). Some 28% of eggs laid in their own nests are later destroyed by conspecific brood-parasites and prey thieves. Some nests are brood-parasitised up to four times, each time by a different female. Miltogrammine flies (Metopia spp.) destroy another 5% of A. sabulosa eggs, so that overall only about two-thirds survive to hatch.
I love going out insecting, as you have gathered, but now and again things don’t go right. From my bicycle being trampled by cows which has just ate my lunch to catching the family jewels while stepping over a barb wire fence. This week when out I thought my water bottle had leaked in my kit bag, until I put my hand in further and found the banana I put in the week before and forgot about, it was all over my spare sun hats (a must when your follically challenged).
I have swallowed small bees when they have crawled back in the sucky end of my pooter, I have fell in nettle filled ditches trying to net something just out of reach. Then there is the dreaded dog poop mine, well hidden in the grass and you are not looking where you are going as your to busy following a flying bee/wasp until you feel that slip underfoot but none of this gets in the way of an insecting outing.
All the time im out I’m thinking the BBC comedy series Detectorists could so have been about insectorists that same niche hobby wandering around fields all day. Passersby asking you if your going fishing because I’m walking around with a little net or are you catching butterflies, so as a penalty I talk them to death, you know I’m a self confessed bee bore. But I have also met some lovely interested and interesting people, well I think they are interested or may be lockdown has just made them desperate for other human interaction.
I do dread the colder winter months if I’m still I the UK and not on a MSF mission but I have lots of study to do. Its funny I see my years pass now not in numbers but seasons veg growing/insecting seasons.
I found a male and female Spilomena sp of wasp today again most likely Spilomena beata. A Specimen has been sent off for extreme micro measuring which is how you get to species on this wasp. My microscope isn’t good enough. You can see how small they are against this wood worm hole, it is at the very limit of my cameras capability. Please see previous Spilomena post for information on this wasp.
This is the most rare of the three British Psenulus species, being restricted largely to the south-east, with scattered records from the south Midlands and Dorset. Falk (1991) additionally lists Essex and Cambridgeshire.
It is found across central and northern Europe and northern Africa and has been recorded at 1600m above sea level in the Alps (Bitsch et al. 2001).
Status (in Britain only) Shirt (1987) listed this species as being Rare (RDB3), but this was revised to Notable A (now Nationally Scarce Na) by Falk 1991. Only recorded for the first time in Britain in 1922, this wasp has increased its range but remains scarce and seemingly restricted to southern England. It is probably still expanding its range and is not thought to be under threat.
Habitat Recorded from a range of habitats where suitable scrub grows in warm, sunny locations.
Flight period Richards (1980) suggested that the activity of this species is more restricted than the other two Psenulus species, being confined to June and July, but Falk suggests a flight period of June to September. A single record gathered for this atlas project comes from May, recorded from Dulwich, London.
Prey collected Danks (1971) notes the collection of adult Homopteran bugs within the family Psillidae (leafhoppers) (c.f. Psenulus concolor, which invariably takes nymphs).
Nesting biology Nests in cut stems of plants or small holes in decayed wood, especially old insect burrows. Danks (1971) noted numerous females constructing nests in the stems of butterfly-bush.The association with this plant and also elder is emphasised by Falk (1991).
Flowers visited P F Yeo (cited in Falk 1991) has observed this species at the flowers of hogweed.
I was out recording and found some dead wood and spent the next two hours watching all the types of wasps, I observed this interaction, a Ancistrocerus sp of wasp sealing up her nest cell while being watched patiently by a Chrysis sp of wasp. The second the Ancistrocerus left the Chrysis sp went down took all the mud out of the hole then reversed in to lay her own egg on the stores. The Ancistrocerus came back pulled the Chrysis sp out then went in spent a while head first in the cell then went on to repair the cell seal.