Illustrated Glossary of Organic Chemistry

Ketotetrose: A monosaccharide having both a ketone (a ketose) and four carbons (a tetrose). Only two ketotetroses are possible: the enantiomers of 1,3,4-trihydroxy-2-butanone, also called erythrulose.

Molecular structure of D-erythrulose, a typical ketotetrose.