These are pretty confusing to tale so i will help you and sum up taming in a few steps.

step1.Kill a male and harvest pheremone.

step 2. feed pheremone to a large dino (i reccomend the bronto).

step 3. find a female and reduce its health to at least ten percent.

Step 4. Let it lay an egg on you large dino of choice.

Step 5. feed your dino cravings and make sure you give it plenty of regular food (it will consume a lot of food while its incubating.) and once the rhyniognathia hatches your dino will sie amd you will have yourself a beatiful bug that carries rexes and shoots sap. :)