Mamook Pears- like... from MAMOOK?

[Enkidoh]

Sadly, it is just your imagination - Hydaelyn is not Vana'diel, they are two totally different worlds, and SE specifically stated this during a past Q@A session for one of the Live Letters which seems to have disappeared (which used to be found on this link, but I saved the post by Bayohne in question for posterity:

Q55: There are a lot of names from Ivalice such as Dalmasca, Belias, and Zodiak that have been mentioned, is there some connection between Hydaelyn and Ivalice?

A55: To be absolutely clear, there is no connection between FFXIV’s Hydaelyn and FFXII’s Ivalice. Likewise there is no connection with FFXI’s Vana’diel. Each are their own individual world. Based on this, there are connections between the things that appear in the world, and we’ll be revealing more in the future.

So yeah, the use of Mamook and mamool'jaa in FFXIV are just fanservice fluff that doesn't mean FFXIV's world is the same as FFXI's (and the final nail in that coffin was the FFXI crossover event featuring Shantotto, she specifically mentions that she comes from 'the Federation of Windurst in the world of Vana'diel', and clearly speaks of Eorzea/Hydaelyn as a totally different world - and that she arrived in Hydaelyn via interdimensional travel). So yeah, that pretty much cements the fact - Hydaelyn is not Vana'diel, or any other FF world - it is it's own individual world.

[Charmin]

Limsa certainly has more extensive ports and vessels that go further afield, at any rate, which probably makes travel to and from Mamook easier from Limsa.

I think that we see further evidence of the MJ being transplanted by doing a bit of BTN:

Sagolii Sage: A savory herb often found growing in parched desert environments. It is used in cooking and various medicinal ointments and unguents.
Black Scorpion: A deadly desert vilekin from whose venom can be extracted a potent paralyzing poison.

The ONLY place you get these two desert-themed items is in the not-desert-themed Bronze Lake area, which is also apparently where the MJ (mostly) live. So perhaps they brought some things with them that took root in the swampy area? What's very interesting though is that even beyond the lizardy link of the MJs are that there are two other ingredients you can only find in the Bronze Lake area that don't have a native home there:

[Charmin]

Rolanberry: A tart fruit-one of few still found growing in the devastated region of Mor Dhona.
Dark Frog: This tiny frog found in the swamps and lakes of the Black Shroud secretes a powerful poison known to induce paralysis.

Perhaps of note, too, is that you can harvest earth shards in this otherwise water-dominant area (maybe even fire because of the hot springs). Was this area at one time desert? There's a quest line in Thanalan that talks about Goobs carrying and transplanting items (and critters?) on their backs, but there's no Goobs in that zone. The closest is in E. LaNosc to the south, but even then the Goobs are way south in that zone. That said, how did we get Mordo fruit and Shroud frogs?

Oakwood has some "native" species, but you also find "Far to the east" sticky rice as well as pixie plums from Coerthas. Hmmm!