“Cocoxenus indagator, a ‘fruit fly’ that starves some solitary bees to death
You may see these little ‘fruit flies’ around your red mason bee nest boxes. This feeble flying insect is no fruit fly as a larva. It is a cleptoparasite . They are opportunists and literally hang around watching and waiting. They are looking to sneak into an empty cell, check it out to see if any pollen has been stored. If it has, she will quickly lay some eggs and leave pretty pronto before the host bee returns. The resulting larvae eat the pollen store and in many cases if there are simply too many of them, the bee larva will starve, usually to death. You can find up to ten larvae in one cell.”
Interesting to find it in a Blue mason bee nest
Helorus rufipes. You don’t get much more obscure than this. It’s one of three British species of the family Heloridae, a family found over much of the globe but not one of the hymenopteran success stories, with only a small number of species. They’re not very big and they are not very flashy but they do live in British woodlands and gardens and are quietly going about their business, laying eggs in lacewing larvae and eating them from the inside. This specimen was on the wall by my back door as I left for work one morning. But you won’t find Helorus in many field guides or many online illustrations. Just one of many obscure families of Hymenoptera that fill our landscape.
Sorry for the blurred photo but it flew before I could get a better one.
I have posted these little wasps before but never with a chrysalis. these wasps are tiny but very numerous on the allotment where we get so many Cabbage white butterflies. The adult injects eggs into the chrysalis where its young develope and eat the pupating caterpillar.
Before emerging the following year to carry on the cycle
There are so many type of parasitic wasp at the moment at the allotment, taking advantage of the caterpillars ,chrysalises , ladybirds and ladybird larvae greenfly etc etc
You learn something new every day, while trying to ID this Aphid type it came to light that these have been mummified , in each one is a Parasitic wasp larvae which will emerge fully developed.
Natural enemies are various species of parasitic wasps that lay their eggs inside aphids. The skin of the parasitized aphid turns crusty and golden brown, a form called a mummy. The generation time of most parasites is quite short when the weather is warm, so once you begin to see mummies on your plants, the aphid population is likely to be reduced substantially within a week or two.
I have just been out to check and sure enough here is a photo I took of the empty bodies and you can clearly see where the wasp has emerged from mummified aphid body.
Today I found the wasp that parasitise the Aphids