If 7 want alot of chiten kill matisis no matter what u use youll usually get at least a hundred. If you use a megatherium u got almost 1000 with a tame. U got a breed one your looking at 1500 each mantis
For those of you that are based on herbivore island, and don't want to fly or sail constantly to satisfy you chitin needs, just tame a frog and hunt the trilobites off the coast. They have no oxy drain and move fast enough to dodge all meg attacks, plus the get lotsa chitin. Just be sure to have lotsa oxy yourself, or an air tank. Happy sea bug hunting!
If you play on Val boosted or not in the section between the ice wyvern trench and the wyvern cave, follow the lava flows in and on the sides there are many Mantises,dung beetles, scorpions, spiders, and centipedes. Any wyvern will work for this but I find ice wyvern to be the best due to your immunity to the other wyverns there. Megatheriums also work really well but it’s a little more convenient to have a wyv.