From BiblePortal Wikipedia

Smith's Bible Dictionary [1]

Ze'phon. (Watch). The son of Gad,  Numbers 26:15, and ancestor of the family of the Zephonites. Called Ziphion in  Genesis 46:16. (B.C. 1706).

Fausset's Bible Dictionary [2]

Zephon or ZIPHON. Son of Gad, from whom sprung the Zephonites ( Numbers 26:15).

Holman Bible Dictionary [3]

 Numbers 26:15 Genesis 46:16

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [4]

(Heb. Tsephon', צְפוֹן , Watch; Sept. Σαφών : Vulg. Sephon ) , first named of the -seven sons of Gad ( Numbers 26:15) and'progenitor of the family of the Zephonites (Heb. with the art. hats-Tsephoni', הִצְּפיּנַי ; Sept. Σαφωνί ; Vulg. Sephonifte ) . In Genesis 46, 16 his name is written Ziphion (Heb. Tsiphyon', הִצְּפיוֹן  ; Sept. Σαφών .Vulg. Sephion ) . B.C. 1874.

The Nuttall Encyclopedia [5]

Of secrets), name of a cherub sent, along with Ithuriel ( q. v .), by the archangel Gabriel to find out the whereabouts of Satan after his flight from hell.