Typhlichthys eigenmanni Charlton, 1933 was described inadvertently in a richly illustrated publication on the comparative anatomy of the central nervous system of blind cavefishes. Characters described by Charlton (1933) are sufficient to differentiate the species from Amblyopsis rosae (Eigenmann, 1898), with which he compared it in a detailed examination of the optic tectum, the primary visual center of the brain. These characters are: 1) a relatively narrow optic nerve, 2) a relatively large tractus mesencephalo-cerebellaris anterior; 3) the rostral bundle of the fibrae tectales nervi optici ascending in front of the nucleus dorsali thalami as opposed to coursing around its anterior pole; and, 4) relatively small brachia tecti. Efforts to locate Charlton’s type specimens of T. eigenmanni, likely histological slides, have not been successful. The type locality is Ha Ha Tonka State Park, Camden Co., Missouri. Putative topotypes are catalogued in collections of the University of Michigan, Museum of Zoology. Typhlichthys eigenmanni Charlton, 1933 is a subjective synonym of T. subterraneus Girard, 1859, the Southern Cavefish.
Typhlichthys eigenmanni Charlton, 1933, an available name for a blind cavefish (Teleostei: Amblyopsidae), differentiated on the basis of characters of the central nervous system