Usually I aim the focus just in front of this point, focusing exactly here does not work well as the eyes remain out of DOF. a little in front of it and the eyes are included, with some importante face structures.
This was a humid leaf, the wasp was thirsty if possible I avoid using honey or sugar, works great for keeping the subject steady but kill some sense of motion present in the scene.
This wasp was sick, the difficulties to cleanup the silk and the fact is with little motion allowing a picture is proof of this.
These reflections are from the flash, is interesting to observe how the light behave different, depending of the subject surface. This photo is pure flash exposed, there isn't natural light in the scene.
The ball joints in the antenna are cool to look at, is possible to confirm this reading carefully the comments, but are not a main target of the photos, could distract to focus in more important aspects, I prefer to consider this part and added bonus when present in the photo.
Mature lemon in background
Another mature lemon, the difference in color is due to sphere format of them and little differences in color in the surface of each one, I prefer to use natural things to compose the background instead of coloured paper cards who turn the background too flat.