Habitat and record. I am much indebted to Miss Miriam Rothschild for kindly presenting me with a female specimen of a new cymothoid isopod taken from the mouth of a fish known locally as Boca-Chica, which, in the words of the collector, is “slightly larger than a herring, scaled, and with a sucker-like mouth”, probably a loricariid, from Rio Napo, Ecuador.