Longfin Smelt Swabbed for Genetic ID (IMAGE) University of California - Davis Caption Longfin smelt can be difficult to differentiate from endangered Delta smelt. Here, a longfin smelt is swabbed for genetic identification through a CRISPR tool called SHERLOCK. Credit Alisha Goodbla/UC Davis Usage Restrictions Provide credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.