What book/accessory did the humanoid Eel-monster the Anguilian appear in?

[Elderbrain]

OOC:

I am wondering where the Eel-like humanoids called Anguilians first made an appearance, but don't know if they were in 2e, 1e or earlier. (I am aware that people have created versions for 3e and 4e, but would like to see the originals.) The name (only) appeared in the 2nd edition accessory Of Ships and the Sea, in the chart showing what depths different creatures could safely descend to, and intrigued me because I'd never heard of them before.

 

[Cleon]

I am wondering where the Eel-like humanoids called Anguilians first made an appearance, but don't know if they were in 2e, 1e or earlier.

They're from a 2E AD&D book by Skip Williams called Monstrous Arcana: The Sea Devils, published in 1997.

There's an official 3E conversion in Stormwrack and an unofficial one in the Creature Catalog here on Enworld, although for some reason it's mispelled Anguiliian.

 

[Elderbrain]

Thank you!