The Alabama Cavefish is only found in a single cave along the Tennessee River in northwest Alabama. This federally endangered species resides in pools with little flow. The Alabama Cavefish is completely adapted for life in total darkness, lacking eyes, pigment, and pelvic fins and having extensive sensory canals and papillae to detect water movement to navigate, find prey, and avoid predation. It differs from all other cavefishes by having a long flat head constricted behind the snout, unbranched fin rays, and incised fin membranes. The more common and widespread Southern Cavefish (Typhlichthys subterraneus) also occurs with the Alabama Cavefish.