The tuna keel is a mechanosensory structure

Here we present the discovery of a novel sensory lateral line canal within the bilateral keels of tunas with long tubules that extend to the upper and lower keel surfaces on each side, accompanied by a suite of internal skeletal modifications associated with the lateral line canal. We further show that neuromast mechanoreceptor organs are found periodically along the canal. These observations suggest that the tuna keel acts as a flow sensing system, which is substantially modified from the lateral line canal present along the body in fishes.

To describe the novel morphology of the lateral line canal in the bilateral keels of tuna, we used a combination of different 3D and 2D imaging techniques. In this repository, we included the following data sets: 1) Raw data of the micro computed tomography scans (µCT scans) of both non-stained and stained keels with phosphotungstic acid (PTA) (.avi files); 2) light-microcopy images obtained with a Keyence microscope from the keel surface and histology stained sections (.tiff files).