Best strategy from what I’ve found

1 first scout the swamp with a spyglass from the back of an argy. This will allow you to see the gender without getting too close.

2) If the bug is a male, kill it and harvest pheromones. If female make a note of location for later. For killing the male use beelzebufo or Megatherium.

3) feed pheromones to a tame with high drag weight. My personal recommendation is Paraceratherium as they are very common and fairly easy to replace. Also the platform saddle plus mini gun turret makes it simple to get a female to ten health

4) track down female and get it to 10% health. If you find yourself with multiple pheromones and multiple sacrifices you can get multiple tames implanted with eggs in one fell swoop.

5) meet creatures very bizarre food demands until baby makes its big entrance and ta da. You now have a giant incectoid assault chopper.

Now that they've come out I've tested them a few times to try and see how they're tamed.

You wanna grab a tame (I used gigas), preferably with good stats and/or one you don't mind losing - and bring it to wherever they spawn on the map you're using. You should go off and kill a Rhynio (any gender) on your own first, or with said tame so that you can harvest a pheromone from its corpse. Once you have that pheromone, feed it to the tame and then go and find another Rhynio (I believe only females can infest your tames, correct me if I'm wrong!) And aggro it to your tame while the pheromone is affecting it. Keep your tame on passive and let the Rhynio do it's thing! You'll have to shoot the Rhynio while it attacks your Dino, and get it below and certain threshold of health. It'll then perform an animation as if it is about to spit resin, but will do some sort of dive/corkscrew into the tame and voila! Your tame is now infested. Your tame will receive strange cravings while it incubates the baby Rhynio, and they're strange. It can be stuff like element it wants, ranging from consumables like battle tartare to even ammonite bile and achatina paste, all kinds strange things. Once the incubation timer goes down, your tame will die and out will hatch a juvy Rhynio! They won't aggro onto you when you hatch them (at least not in my experience) so super easy to just run up and claim them!

You also can't breed them, I don't think. Doesn't let me anyway, which isn't fun.

Ok. One of these things killed my argy level 100 with 3000 health and she died so fast. So I came back to the swamp on Big Bill. My level 97 spino. I quickly got the pheromone then I went home got on Titan my bronto Bill followed us we sat at a red wood edge. We accidently killed the level 25 female but a level five impregnated Titan. I couldn't get any cravings the baby was born I named him Titan after his mom. And after giving him a saddle I killed 6 trikes before he was even level 10. TAME THESE BUGS

Quick question, do yall know if I can avoid giving creatures cravings and avoid imprints. I want to tame a trike for this creature. But I don’t know if I can get it without the imprints and expensive cravings. Just for a starter rhynio. And will the rhynio be alive and adult. I don’t need it op I just can’t find an argy or a quetz to tame and all the pts on my single player are max level 30.

Here's just some things I've learned while taming these huge bugs.

•If you don't have something like a giga/carcha to impregnate, the 3rd best option would be a Brontosaurus for best stat quality for your baby bug. Though actually getting one to the Rhyniognatha will be quite difficult as you can't simply cryopod it and throw it once you found your Rhyniognatha (as of the Cryofridge and cryopod change in ASA). So you may need to walk it through the entire swamp...

• Keep your shoulder pets passive! This won't affect you if your using a large dino such as those listed above, though if using something smaller (though this is not recommended, most smaller dinos can't even consume the pheromone), you need to have your shoulder pets on passive so they don't attack the Rhyniognatha. I once did this mistake, and as I was going to feed my dino a pheromone, my otter on my shoulder killed the Rhyniognatha as it was on Attack Target.

•Final one, be fully prepared! Bring your pheromone and your creature your willing to impregnate before searching for a Rhyniognatha. This is because these guys love to aggro absolutely everything and get themselves killed, so if you went back to stock up on everything you need once you found one, chances are it is already dead.

Wish you luck!

On mobile it chooses a new craving directly after you feed a craving to your dino similar to imprinting, but you wont see it until the cravings cooldown is up.

This means if you are save scumming to get better cravings you should do it before you feed a craving to your dino, then after you feed it wont tell you the next craving so you need to wait until the cooldown timer is up, then if you get a bad craving you need to download and wait out the cravings timer again.

this also applies to the first craving you need to save before your dino dies instead of before the first craving timer ends if you want to roll a new first craving

If you save seconds before the cravings timer is up, you will get the same craving every time you download your save.

In terms of baby stats:

This has to be looked at as a Mating of your Host creature and the wild female Rhyni you getting the baby from rather than regular taming. Which means like regular breeding the baby can inherit stats from either.

The requrements to inherit the max amount of stats from the host (apart of the usual breeding chance to inherit stats from either female or "male") seems to be at this point:

-fulfill all carvings

-use either a giga, caracho or bronto as host creature

failing to do so reduces the posiible stats by a fairly high %

Only 2 will spawn on map at a time. Spawns are along the swamp River just south of the redwoods. Kill the males and take the pheromone from inventory(shotguns work well on them). When you find a female, have a tame nearby preferably a paracetamol for your first time. Damage the bug and peck at it with a low damage weapon to get below 10%. Put your tame on passive and feed it the pheromone. The rhynio will beat on it for a little bit but don't stress, it will fly up and whip down and impregnate your tame. (If you build a trap you can impregnate multiple tames, I've done 35 dinos off of 1 bug)