bees, wasp & caterpillar

[asheleaf]

While ion the Lizard in Cornwall I came across some leafcutter bees nesting in the side of a sand dune and hunting around their holes was a large wasp. While attempting to get some photographs i noticed the sand 'moving' at the base of the dune. Something was clearly tunneling just below the surface of the sand. I dug it out and was very surprised to find a larva of some sort?

Anyone ideas anyone?

thanks, Ashe

[mickmassie]

I'll be interested to see what others think about this.
From what I know, the British parasites of Megachile are Coelioxys bees, not wasps. I think your wasp may be Astata boops, and they use shieldbug nymphs to feed their young.
I have no explanation for the larva, but I know that many different species of wasps and bees may use a suitable sandy habitat, so it may not be related to those you photographed. Ammophila maybe ?
Mick.

[col188]

[quote=asheleaf;513321]While ion the Lizard in Cornwall I came across some leafcutter bees nesting in the side of a sand dune and hunting around their holes was a large wasp. While attempting to get some photographs i noticed the sand 'moving' at the base of the dune. Something was clearly tunneling just below the surface of the sand. I dug it out and was very surprised to find a larva of some sort?

Anyone ideas anyone?

thanks, Ashe



]

As a gardener I'd recognise it as a Cutworm, Which I believe is the underground Larval stage of some Moths (Noctuid)
Col

[eucera]

The bees are female leaf-cutters Megachile dorsalis (=M. leachella). Typically a ground nester and forund on dunes. The wasp is Podalonia hirsuta. the wasp is not parasitic on the bee BUT they feed their grubs on Noctuid Moth larvae

[mickmassie]

Very good Eucera, makes a neat story of the pictures.
What tells you the wasp is Podalonia ? I would love to be able to distinguish these in the field. Is it the abdomen shape and length ?
(I could tell it wasn't Ammophila, but that is about it).
M.

[asheleaf]

thank you everyone for all your help. Thanks Col for spotting the Noctuid moth larva. And thanks eucura for putting the pieces of the puzzle in the right place. It certainly all fits. The wasp was hunting across the sand rather than on plants. I did wonder why it wasnt having any luck with bees!

cheers, Ashe

[eucera]

Podalonia and Ammophila are closely related genera. In Ammophila the abdomen is longer and slimmer.

2 species of each genus in UK.