Discovery of a specialised anatomical structure in some physoclistous carangid fishes which permits rapid ascent without barotrauma

Physoclistous fish are unable to rapidly ascend through the water column without significant risk of barotrauma via swim bladder hyperextension or rupture. Here, we report on the discovery of a highly specialised anatomical structure which permits some physoclistous fish species, the samson fish Seriola hippos and silver trevally Pseudocaranx georgianus, to vent swim bladder gas during ascent. Dissections of injected casts and X-ray imaging...