Golden Beetle

There are lots of these beetles, specially rare ones at the same location as Barrier Hermit Crabs, in Tusk Isle and Isle of Fang, the small islands to the south of Zandalar harbor. They usually show up as Hermit's second. So you just need to engage in a pet battle against a Barrier Hermit, and Golden Beetle and Leafy Flutterwing will join the fight.

No idea why even in the map Golden Beetle is listed as if it were exclusive of the Atal'Dazar area.

I also got several Golden Beetles as secondary pets around the southern island where you can find the Barrier Hermits.

This reminds me of a golden stag beetle

The golden Beetle can be found in Atal'dazar not in the dungeon, but when you are just outside of it, to the right there's a mud path, that lead to the upper level of the dungeon, and you can move over the pyramid there. and there's a few of wild golden beetle in the area

A very interestingtanky  pet for PvP with Shield, Crouch and a decoy breaker in Flurry. All those moves benefit from speed so I would pick the S/B breed over the more obvious P/P option.