Lizardfishes are generally small, although the largest species measures about 60 cm (24 in) in length.

They have slender, somewhat cylindrical bodies, and heads that superficially resemble those of lizards.

They are distinguished by the presence of black blotches in their guts, clearly visible through their transparent, scaleless skin.

[3] The four species comprising the genus Saurida are S. umeyoshii, S. pseudotumbil, S. undosquamis, and S. tumbil.

The extinct Argillichthys is represented only by a single species, A. toombsi, from the Eocene-aged London Clay formation.