This mob has no set spawn location - I have found it all over the zone. It can spawn from any mob in the zone with a few exceptions where the mobs are set to one type. If you kill a wolf, that mob may be a skellie or a snake the next spawn cycle or even a wisp. This mob will spawn in place of any roaming or static mob out there that is set to random.
That's interesting. Because I've never seen it on the "right side" of the temple of bertoxx...coming in from Ocenagreen hills, looking towards the viallge and ocean. Only on the left side. Pretty much, where the wisps spawns. Incidently, this mob is a wisp. I know, I know. It's an amazing coiincidence. It spawns in this general location tho.
If you step just outside the village and look immediately to your left, you will see two skelly mobs. I've never seen it spawn there. Ever. And I've hkille those quite a few times.