This pair of clearwing moths (oomomobuto-sukashiba) were very difficult to access – on some vegetation in the middle of a stream and it was also getting dark – hence the terrible focus. Better JPmoth pictures here. Looking quite similar to bumblebees, they are probably less prone to predation by birds.

Melittia sangaica nipponicaMelittia sangaica nipponicaMelittia sangaica nipponica

Lepidoptera: Sesiidae
Melittia sangaica nipponica = oomomobuto-sukashiba
Large clearwing moth