Unsure if this is a beetle larva so have placed it under 'Beetles' for now. A second one on the same bush is shown in following sighting 4386014. There appears to be some destruction of the leaves where both insects have been.
Just to throw in another option, the body shape kind of reminds me of the brown hoverfly larvae & green hoverfly larvae ( Syrphidae sp.) that I see eating aphids when my veges go to seed? I can see the head end as it tapers (& the bum end is pooping). Did you get to see how it moved ie did the head come to a narrowness like a maggot does as it crawls? PS. This obs appears to show feeding on soft scale insects & Syphidae sp. are predators of aphids, scale, thrips & caterpillars. Some examples for you in the link below: https://www.inaturalist.org/taxa/49995-Syrphidae/browse_photos?term_id=1&term_value_id=6
@DiBickers Thanks for the comment, Di. The sighting was some time ago now but I'm certain that I didn't see any movement at the time. I've kept an eye out for more of these over the years but haven't seen any. I'll check the link. Thanks, Tim