Shathak is the wife of Tsathoggua and the mother of Zvilpogghua. The being mated with Tsathoggua to produce Zvilpogghua on the planet Neptune according to the Parchments of Pnom. The name's similarlity to Shantaks is probably conincidental. Also called Chushax and Zishaik in other texts.
Shathak (and variants Chushax and Zishaik) were created by Clark Ashton Smith, but not elaborated upon. Laurence J. Cornford correlated some elements.