Emergent growth from an Abax beetle?

Emergent growth from an Abax beetle?

Observation - Emergent growth from an Abax beetle?. Description: Found this beetle, already dead and pretty dry & brittle, in an Ancient Oak-Beech forest on the litter floor. I'm not sure what this is, it kind of resembles a leaf-bud from a tree, but it also makes me think of those fungi that parasitise certain ins

Found this beetle, already dead and pretty dry & brittle, in an Ancient Oak-Beech forest on the litter floor.

I'm not sure what this is, it kind of resembles a leaf-bud from a tree, but it also makes me think of those fungi that parasitise certain insects?

It appears to be emerging from underneath the beetles head, below the mandibles. As mentioned, it was already quite dead, no flex in the legs, and felt light, so maybe it'd been dead for some time. However the "growth" looked fairly fresh?

This is a focus-stacked macro image taken using a Canon 5D MkIII and MP-E 65mm lens, and processed with Zerene Stacker and Photoshop.