Kuo-Toa

The Kuo-Toa race was most likely based on the Deep ones from the Novella "The Shadow over Innsmouth" made by H.P. Lovecraft in 1936. Here is a long description of the deep ones from the story:

"Flopping, hopping, croaking, bleating—surging inhumanly through the spectral moonlight in a grotesque, malignant saraband of fantastic nightmare. And some of them had tall tiaras of that nameless whitish-gold metal . . . and some were strangely robed . . . and one, who led the way, was clad in a ghoulishly humped black coat and striped trousers, and had a man’s felt hat perched on the shapeless thing that answered for a head. I think their predominant color was a greyish-green, though they had white bellies. They were mostly shiny and slippery, but the ridges of their backs were scaly. Their forms vaguely suggested the anthropoid, while their heads were the heads of fish, with prodigious bulging eyes that never closed. At the sides of their necks were palpitating gills, and their long paws were webbed. They hopped irregularly, sometimes on two legs and sometimes on four. I was somehow glad that they had no more than four limbs. Their croaking, baying voices, clearly used for articulate speech, held all the dark shades of expression which their staring faces lacked."

In Dungeons and Dragons, Kuo-Toa have the same description but have a special ability; if they get inspired in mass amounts by an unknown power, they will create there own real god of its likeness.