Found a cheap way to farm them as a new player in Ark Mobile.
Spawn at Location S2 and have a weapon in hand so your punches won’t decrease your health. More damage = better.
Take off any armor because they do chip damage with torpor meaning damage overtime which is bad.
Head towards the ocean and submerge for a few seconds just to taunt the Cnidaria deep in the ocean.
Emerge to the surface and walk off some so distance.
By some miracle/magic when you come back for a few second, some spawn/came up to the surface where you can see their cyan body. From there, try to beach one of them or more. DO NOT, under any circumstances, think they are harmless when beached. Attack far enough that you won’t get yanked into their attack, come to you with the last bit of water they can move in, and so none of your land tames following you get caught. I went from having 102 neurotoxins to about 500 with this “exploit”. Enough to tame my Therizinosaurus when I don’t have kibble to tame her.