In our study, foraging U. coroides tilted its body less than did E. gula, a trait which may be related to the ventral position of mouth in the former, as recorded for Menticirrhus saxatilis (Bloch & Schneider, 1801), whose inferior mouth allow it to dig with few changes in its swimming position (Chao & Musick, 1977). Both U. coroides and E. gula feed on benthic crustaceans, but only E. gula eats polychaetes. This major difference in diet may be related to E. gula visual inspection of substrate and its tubular mouth, which allows it to reach more deeply in the sand.