Cimolichthys nepaholica (Cope 1872) Barracuda of the Western Interior Sea Copyright © 2004-2012 by Mike Everhart Created 07/28/2004: last updated 07/18/2012   LEFT: Cimolichthys nepaholica from a detail in a mural at the University of Kansas Museum of Natural History, Lawrence, Kansas.

One of the more common species of fish found preserved in the Smoky Hill Chalk is a medium-sized predatory fish called Cimolichthys nepaholica. It was also the first specimen of articulated remains of anything that I ever found in the chalk.  The pictures at LEFT and RIGHT were taken in 1968 after I had uncovered a fairly large Cimolichthys that had been preserved more or less upright on the sea bottom. The remains were discovered low in the Smoky Hill Chalk (about MU 2 - Late Coniacian) of Ellis County.

LEFT: A large and fairly complete Cimolichthys nepaholica in the exhibits of the University of Kansas Museum of Natural History. This specimen is about 2 m (6 ft) in length, and shows the large scutes (heavy scales) that are typical of the species. Note that the top of the skull is actually more convex than the concave appearance preserved in this specimen and the above painting.

The genus name Cimolichthys (cimoli = (Greek) a white chalky clay; ichthys = fish) had been coined by Leidy in 1857 in describing fish remains (C. levesiensis) from the English Chalk.  According to Alvaro Mones  (pers. comm., 2004), "cimoli is new Latin (from Greek - kimolia), a white clay from the Aegean island of Cimolus of the archipelago of the Cyclades. In Antiquity it was well known for the high quality of the dried fishes it produced." Earl Manning (pers. comm., 2004) noted that the English type species C. levesiensis was named for the town of Lewes, in Sussex where the fossil was found.  The Lewes Formation was named later and is the basal member of the English upper chalk. This chalk formation (Turonian) makes up part of the White Cliffs of Dover.

Two years later, Cope (1874, p. 46) revised the spelling of “nepaholica” to “nepaeolica” (nepæolica), changed the genus of C. sulcata to "Empo" sulcatus,  and changed C. semianceps to "Empo" semianceps, and also added two new species of "Empo":  E. merrillii and E. contracta.  While C. gladiolus eventually became recognized as Enchodus gladiolus, C. anceps literally disappeared. Goody (1976, p. 102) noted that the type specimen could not be found. Goody also determined that, based on Cope's description of the type, the specimen was more likely the ectopterygoid of Enchodus petrosus.

As noted above, Leidy's Cimolichthys lavesiensis is much older (Turonian) than the specimens of "Empo" nepaholica examined by Cope (Late Coniacian - Early Campanian). It doesn't appear that Cope ever accepted that Cimolichthys Leidy and "Empo" Cope were the same genus. Cope (1875, p. 230) noted that he “formally referred some of the species of Empo to the genus which embraces the fish called by Leidy Cimolichthys levesiensis; but I find that they do not possess the same type of teeth. … The genus therefore takes this name [Empo].”  Cimolichthys specimens are usually poorly preserved and the teeth are quite fragile. Cope (1875, Plate 52 and 53) was the first to illustrate Cimolichthys.  Manning (pers. comm. 2004) noted that Cope is one of a few to figure the isolated dermal scutes (ibid., Plate 53, fig. 9). LEFT:  RIGHT: Dermal scutes of Cimolichthys nepaholica on the exhibit specimen at the University of Kansas.

"Empo" nepaholica and the four (six?) new Cimolichthys / "Empo" species of Cope were actually fragments of the same kind of fish, and all were synonymized by Loomis (1900 - in German) and by Hay (1903). By virtue of being the first of the species names published in Cope's (1872) paper, the species is rightfully called nepaholica*. Since the genus name Cimolichthys Leidy 1857 has precedence over that of "Empo" Cope 1872, the correct name for Cope’s many “species” becomes Cimolichthys nepaholica. Like the very similar problem with Xiphactinus Leidy and "Portheus" Cope, the name "Empo" has had a long, if ill-deserved, life of its own and is still found on labels in museum exhibits and collections. As for the other species names, Goody (1970, p. 2) indicated “there is no reason for retaining Cope’s various species that are based mainly on isolated teeth and fragments of jaw bones.” 

(* NOTE: The species name most likely comes from "Nepaholla," an earlier Indian name for the Solomon River (Solomon’s Fork of the Smoky Hill River) meaning "water on a hill" (Rydjord, 1972, p. 109).)

While not closely related, Cimolichthys can be visualized as being a Cretaceous barracuda (or a freshwater pike, as suggested by Cope) in appearance. However, Cimolichthys, like Enchodus, is in the same order as modern salmon. The fish grew to almost 2 m (6 ft) in length and the skull, with triple rows of teeth set in the narrow lower jaws (Hay, 1903) is readily recognizable.  Cope's (1875) Figure 6 in Plate 53 also shows 3 rows of teeth on the dentary and in his description of the genus "Empo" (ibid., page 228), he mentions that “the dentarys support several series of teeth; one of the large ones on the inner side and several smaller on the outer.” While their remains are frequently found, good specimens are rare because the skull is lightly constructed and tends to either have come apart prior to preservation or as a result of weathering.

LEFT and RIGHT: A dorsal view of the skull of a large Cimolichthys (FHSM VP-73) in the Sternberg Museum collection that is preserved in an unusual dorso-ventral orientation.  Note the ornamentation on the top of the skull (neurocranium), and the operculum (RIGHT) that covers the gills .

LEFT: Restoration of the skull of Cimolichthys levesiensis in lateral view (after Goody, 1969). RIGHT: Restoration of the jaws (right) of Cimolichthys levesiensis in medial view as taken from BMNH P.1811 (after Goody, 1969).

We can assume that Cimolichthys had a voracious appetite for fairly large prey because of a number of specimens that have been found with the remains of an undigested last meal inside. One of the strangest “death by gluttony” occurrences in the fossil record was reported by both Kaufmann (1990), and Stewart and Carpenter (1990; see also Carpenter, 1996) in regard to a specimen of Cimolichthys discovered in the Pierre Shale of Wyoming.

LEFT: In this instance, the Cimolichthys (UCM 20556 - skull at far left) apparently died with a large squid (Tusoteuthis longa - UCM 29667) lodged in its mouth. The squid had been swallowed tail first as evidenced by the gladius (squid pen) being found inside the body of the Cimolichthys. However, the open jaws of the fish appear to indicate that part of the head and/or tentacles of the squid were still outside the mouth. This probably meant that the fish’s gills were blocked from getting oxygen from the water, causing death by suffocation. (2012 photo by Trish Weaver; See also Fig. 176 in Kaufmann, 1990).

            Another unusual Cimolichthys specimen (FHSM VP-15065) in the Sternberg Museum was collected by Greg Winkler and Pete Bussen in the early 1990s from the lower chalk (Late Coniacian) of western Gove County. In this case, the skull of a large (1.8 m) Cimolichthys was found eroding out of the chalk.  Much of the skull was already lost, but the rest of the fish was complete back to the tip of the tail. When the specimen was initially prepared, it was found to contain not only a large Enchodus (FHSM VP-15066) but also the remains of another smaller, unidentified fish (FHSM VP-15067) as a last meal. At this point, it’s uncertain if both fish inside the Cimolichthys were consumed by the larger fish, or if this a classic case of a “fish-in-a-fish-in-a-fish.” In either case, the partially digested condition of the Enchodus leads me to believe that the Cimolichthys died within a short time after eating it.

In a similar situation, I found a 1.3 m (4 ft.) Cimolichthys (FHSM VP-14024) with a .7 m (2 ft.) long,  partially digested Enchodus petrosus (FHSM VP-14025) inside in the lower chalk of southeastern Gove County in 1994. Both palatine bones of the Enchodus, minus the large fangs, were located near the anus of the larger fish. Besides being an indication that the prey had been swallowed head-first, it also explains our field observation of finding an unusual number of partially digested Enchodus palatine bones, and no other associated remains.  Being the heaviest bones in the skull of the Enchodus, mostly indigestible and located at the anterior end of the skull, they were probably expelled while the rest of the prey was still being digested. The large teeth, however, appeared to have been broken off the palatines and were not found in the rest of the remains.

The skull of Cimolichthys has been figured by Cope, (1875), Loomis (1900), Hay (1903) and Goody (1970). The photos below show features that are not found or are poorly represented in these papers. 

	LEFT: The damaged left lower jaw (dentary) of a fragmentary specimen of Cimolichthys in medial view. Note that the teeth are leaning forward. The outside edge of the jaw is at the top of the picture. RIGHT: Two Cimolichthys teeth in a jaw fragment.
	LEFT: A close-up of the left dentary at above left, showing the characteristic three rows of teeth (tiny, small and large). RIGHT: Lateral and medial views of the right palatine of Cimolichthys. (Scale = mm)

LEFT: Vertebrae from a large, but scattered Cimolichthys (EPC 1988-16) that we collected in October 1988 from Gove County. These vertebrae were from right behind the skull.  (Scale = cm) RIGHT: Close-up of two vertebrae from EPC 1988-16. (Scale = mm)

It is probable that Cimolichthys was preyed upon by larger fish and mosasaurs. Although they were not noted by Bardack (1965) as being the stomach contents in any of the Xiphactinus audax specimens he surveyed, I did find partially digested Cimolichthys vertebrae in the abdominal region of a Tylosaurus proriger (FFHM 1997-10) that I collected in 1996-97. While their remains have not been reported to be preserved as stomach contents of other predators, many of the severed tails which we commonly find in the chalk are from Cimolichthys (See a much larger, detached Ichthyodectid tail here).

One interesting feature often observed in Cimolichthys remains in the field are the “cone on cone” calcite crystals (steinkerns) that often fill the conical hollows between the deeply cupped vertebrae.

LEFT: The crushed skull of the exhibit specimen (dorsal and right lateral view) of Cimolichthys at the Sternberg Museum of Natural History. RIGHT: A ventral view of a small Cimolichthys skull in our personal collection. Found by Pam Everhart in 1988. Parts of the hyoid apparatus are visible in this view.

LEFT and RIGHT: Details of the jaws from a Cimolichthys skull in the exhibits of the Fryxell Museum of Geology, Augustana College, Rock Island, IL. This specimen was collected and prepared by George F. Sternberg.

	LEFT: A dorsal view of the dentarys of Cimolichthys (FHSM VP-2469) RIGHT: A ventral view of the vomer of Cimolichthys (FHSM VP-2470) showing the teeth.  See a close-up of another specimen HERE.
	LEFT: A left lateral view of the crushed skull of a Cimolichthys nepaholica (FHSM VP-2971. RIGHT: A close-up showing the scleral ring around the left eye of FHSM VP-2971. Note the long, toothless left maxilla going diagonally across the skull.

Other Oceans of Kansas webpages on Late Cretaceous fish:

Field Guide to Sharks and Bony Fish of the Smoky Hill Chalk

Sharks:

Kansas Shark Teeth

Cretoxyrhina and Squalicorax

Ptychodus

Chimaeroids

Bony Fish

Pycnodonts and Hadrodus

Plethodids:

Pentanogmius

   Martinichthys

   Thryptodus

Bonnerichthys

Protosphyraena

Enchodus

Cimolichthys

Pachyrhizodus

Saurodon and Saurocephalus

Xiphactinus

Suggested references:

Bardack, D. 1965. Anatomy and evolution of Chirocentrid fishes. University of Kansas Paleontology Contributions. Article 10, 88 pp. 2 pl.

Cope, E. D. 1872. On the families of fishes of the Cretaceous formation in Kansas. Proceedings of the American Philosophical Society 12(88):327-357.

Cope, E. D. 1874. Review of the vertebrata of the Cretaceous period found west of the Mississippi River. U. S. Geological Survey Territory Bulletin 1(2):3-48.

Cope, E. D. 1875. The vertebrata of the Cretaceous formations of the West. Report, U. S. Geological Survey Territory (Hayden). 2:302 p, 57 pls.

Goody, P.C. 1969. The relationships of certain Upper Cretaceous teleosts, with special reference to the myctophoids. Bulletin of the British Museum (Natural History), Geology, Geological Series Supplement 7, 255 p.

Goody, P.C. 1970. The Cretaceous teleostean fish Cimolichthys from the Niobrara Formation of Kansas and the Pierre Shale of Wyoming. American Museum Noviates 2434:29 pp.

Hay, O. P. 1903. On a collection of upper Cretaceous fishes from Mount Lebanon, Syria, with descriptions of four new genera and nine new species. Bulletin of the American Museum Natural History 19:395-452, pl. XXIV-XXXVII.

Kauffman, E.G. 1990. Cretaceous fish predation on a large squid. pp. 195-196 In Boucot, A.J., Evolutionary Paleobiology and Coevolution. Elsevier, Amsterdam.

Leidy, J. 1857.  Remarks on Saurocephalus and its allies.  Transactions of the American Philosophical Society 11: 91-95, with pl. vi.

Loomis, F.B. 1900. Die anatomie und die verwandtschaft der Ganoid- und Knochen-fische aus der Kreide-Formation von Kansas, U.S.A. Palaeontographica, 46:213-283.

Rydjord, J. 1972. Kansas place names. Univ. Oklahoma Press, Norman, OK. 613 pp.

Stewart, J. D. and Carpenter, K. 1990. Examples of vertebrate predation on cephalopods in the Late Cretaceous of the Western Interior. pp. 203-208 In Boucot, A.J. (Ed.), Evolutionary paleobiology of behavior and coevolution. Elsevier, New York.