These mobs seem to go lower than level 56. My 55 Mage went exploring at the weekend and pulled one that was dark blue: unfortunately it ate 80% of my epic pet's health in a few seconds so I valiantly zoned out :).
Considering Fluffy has off-tanked red-con mobs in Droga, it does seem that they must hit harder here than other new/revamped Kunark zones.
Note that this mob is actually classed as undead, not animal: the Necromancer undead-only slow spells work on them, and once slowed they're easy for Legacy of Zek to tank down with a couple of Shadowbonds for heals.
That said, I did have one resist the slow five times in a row before it stuck! However, in half a dozen kills that's the only one that's resisted anything.