Developmental change in neuromast distribution in the anterior lateral line of muskellunge (Esox masquinongy)

The lateral line system of teleost fish is comprised of individual sensory elements, neuromasts, which together form a mechanosensory system. Because neuromasts have been studied in relatively few species, the biology of the lateral line in diverse taxa of fishes remains an open area of inquiry. Musky are predatory fish native to central North America; these prized game fish have been extensively propagated and introduced to many locations. This study investigated the development of neuromasts in the anterior lateral line system of muskellunge. I hypothesized that as juvenile muskellunge grow, the number of neuromasts in the anterior lateral line would increase. Live staining with DASPEI, fluorescence microscopy and image analysis were used to determine the number and spatial distribution of head neuromasts in developing muskellunge. Results indicate that the number of head neuromasts increases over early development; specifically, neuromast number increases in the pre‐orbital line, a sub‐region of the anterior lateral line. This change was further determined to occur via increased neuromast density, as opposed to elongation of the preorbital line. These findings contribute specifically to understanding of muskellunge sensory biology and generally to development of the lateral line system. This work was supported by Westminster College's Drinko Center for Experiential Learning.