Escolar, a fish famous for causing diarrhea and anal leakage, has been found masquerading as tuna at sushi restaurants, according to a DNA research study recently published by a group of scientists. The escolar was found five times during the brief research project, which included visits to 31 sushi restaurants in NYC and beyond. The study also found that some restaurants are also selling endangered southern bluefin tuna.

The study is part of an effort to build a database of every fish species on earth, which might one day enable anyone with a handheld DNA reader to identify their fish. According to the report (which doesn't name the restaurants), "nineteen of 31 restaurants erroneously described or failed to identify the sushi they sold. Twenty-two of 68 samples were sold as species that were contradicted by molecular identification... The five samples of escolar sold as a variant of 'white tuna' are considered a misrepresentation because this species is a snake mackerel, belonging to the distantly related family Gempylidae."

Last August, a group of high school seniors spent about $300 collecting sushi samples from NYC restaurants and groceries, then sent them off to a lab for DNA bar code analysis. Two out of the four restaurants were found to be serving cheap tilapia passed off as expensive white tuna, and six out of ten grocery stores had fake fish. According to Wired, before these hand-held DNA devices can become the perfect stocking-stuffer, zoologists need to first agree on a system to condense the genetic information from each fish into a concise "signature."