Sand wasp carrying a caterpillar

Sand wasp carrying a caterpillar

Observation - Sand wasp carrying a caterpillar - UK and Ireland. Description: A sand wasp carrying a caterpillar in sand dunes, but which one? I initially assumed this was the commoner of the 2 options found in east Dorset Ammophila sabulosa, but in checking carefully how to distinguish Ammophila pubescens, it seems the crucial f

A sand wasp carrying a caterpillar in sand dunes, but which one? I initially assumed this was the commoner of the 2 options found in east Dorset Ammophila sabulosa, but in checking carefully how to distinguish Ammophila pubescens, it seems the crucial feature is the shape of the "3rd submarginal wing cell…" i.e. the final small cell inside the large outer wing cell. In sabolosa it's rectangular, fully attached to the big outer cell, in pubescens it's "petiolate" and looks like a little goblet attached to the outer big cell by a "stalk" I don't have the perfect angle of view, but am pretty sure the crop attach (flipped vertically to match it to images of the wing venation I can find e.g. on: https://www.flickr.com/photos/63075200@N07/6841765604/ and http://www.bwars.com/index.php?q=wasp/sphecidae/ammophila-pubescens ) shows a petiolate 3rd submarginal, so I think this is A. pubescens