Variations: Diamond fish, Devil fish, Jack fish, Garjack, Litholepe, Litholepe adamantin, Litholepis adamantinus

John James Audubon is remembered today as an artist and ornithologist of considerable import. His practical jokes are less well known, and began with the unexpected arrival of Constantine Samuel Rafinesque at Hendersonville, Kentucky.

Rafinesque was a brilliant, enthusiastic, “exceedingly remarkable”, and very eccentric young naturalist who tested Audubon’s hospitality. After they had retired to bed, Audubon was roused by a commotion coming from Rafinesque’s room. As he describes it, “I saw my guest running naked, holding the handle of my favorite violin, the body of which he had battered to pieces in attempting to kill the bats which had entered the open window!” Rafinesque was convinced the bats were new species. Audubon was not amused.

Perhaps to avenge his smashed violin, Audubon decided to take advantage of Rafinesque’s credulity and eagerness to describe new species. He solemnly supplied Rafinesque with 10 drawings of completely fictitious fish, which were duly named and described in detail. The likes of the bigmouth sturgeon and the flatnose doublefin caused headaches for ichthyologists and tarnished Rafinesque’s reputation beyond repair.

The Devil-jack Diamond-fish (Litholepis adamantinus) is surely the most remarkable of those faux fishes, as evidenced by Rafinesque’s breathless description. This “wonder of the Ohio” is found only as far up as the falls and probably in the Mississippi as well. Rafinesque claimed to have seen it from a distance, and seen some of its scales, but otherwise he “principally relied upon the description and figure given [him] by Mr. Audubon”.

We are fortunate enough to have a complete and detailed description of the devil-jack. It is classified among the garfish but is quite unique. The body is blackish and fusiform, 4 to 10 feet long and up to 400 pounds in weight. The head takes up a fourth of the total length. The snout alone is large (as long as the head), convex above, and obtuse. The eyes are small and black, with the nostrils in front of them. The mouth is transverse and has large angular teeth. Dorsal and anal fins are of equal length, the tail is obtusely bilobed, and there is no lateral line. The body is covered in oblique rows of conical pentagonal brown scales, half an inch to one inch in diameter; they become the color of turtle shell when dried.

The scales are the devil-jack’s main claim to fame, as they are hard as flint, completely bulletproof, and repel hooks. They produce sparks when struck against steel. Only nets or the strongest hooks can take a devil-jack. It is inedible and a voracious hunter, usually seen lying motionless at the surface like a log. The scales are a miracle of nature, for “they strike fire with steel! and are ball proof!” [sic]

References

Jordan, D. S. (1886) Rafinesque. The Popular Science Monthly, June 1886.

Rafinesque, C. S. (1820) Ichthyologia Ohiensis. W. G. Hunt, Lexington, Kentucky.