Fossil Fish from Nebraska
As of August 9, 2006, there are 58 images on the Fossil Fish from Nebraska web site.
- Introduction
- Historical
- Iniopterygian Fishes
- Orodont Shark Teeth
- Eugeneodontid Sharks
- Cladodont Sharks
- Euselachian Sharks
- Xenacanthid Sharks
- Petalodont Teeth
- The Pristodonts
- Chimaeroids, Skates, Rays
- Paleoniscoid Fishes
- Platysomoid Fishes
- Miscellaneous Shark and Fish Remains
- References
- Fossil Fish from Nebraska was compiled by
Fish fossils from the Late Pennsylvanian and Early Permian of Southeastern Nebraska
Specimens collected by
- William Rushlau
- Ed Schafer
- W. D. “Ted” White
- Roger K. Pabian
Images by
- Ed Schafer
- Roger K. Pabian
Most of the vertebrate remains that have been found in the late Pennsylvanian and early Permian strata of southeastern Nebraska are elasmobranchs, a group of fishes that includes sharks, rays, chimaeroids, sawfish, and guitar fish. These fishes have wholly cartilaginous skeletons. Their placoid scales and teeth are similar to the teeth of higher vertebrates, having a layer of enamel covering a layer of dentine that encloses a pulp cavity. The most primitive elasmobrahchs have seven gill slits and more advanced forms have five. Elasmobranchs of the late Paleozoic seas filled several ecological niches and include forms that were carnivores with flesh cutting teeth, carnivores with teeth modified to crush shells, and teeth that may have functioned as filters to extract plankton including algae and small animals from the sea water. One form of tooth found in the Kiewitz Shale may have functioned much like the “beak” on the modern parrot fish that feeds on corals.
The late Pennsylvanian and early Permian rocks of southeastern Nebraska and the adjoining areas have produced some outstanding examples of fish fossils from black, offshore shale horizons that represent the deepest water during marine transgressions that have periodically covered the North American Midcontinent. These sedimentary deposits are called cyclothems and they include both continental and marine sequences. A typical cyclothem in the model put forth by Heckel and Baesemann (1975) and Heckel (1977) begins with a nearshore shale that is of continental origin. The continental deposits are followed by tidal, mud flat, and lagoon or estuary deposits that may contain sandstone beds laid down by ancient streams. The upper part of the near shore shale may contain marine invertebrate fossils such as brachiopods, mollusks, and occasional fish teeth or spines. These deposits are followed by the deposition of a fairly thin, dense, finely crystalline limestone that is called the transgressive limestone. The transgressive limestone may contain an abundant and diverse fauna but most of it has to be identified by studying thin sections or polished sections of the rock because the fossils are extremely difficult to be removed from the dense, hard matrix. At the top of the transgressive limestone, one can commonly observe almost intact fossil communities with many different kinds of marine invertebrate and vertebrate fossils. The offshore shale has a non-black portion in its lower reaches and here the fossil abundance and diversity is probably the greatest of all that are found in the cyclothem. This is because there are numerous niches to be filled, the water is sufficiently shallow to allow algae growth and carbonate production, and establishment of a long food chain. Most of the fossils from this part of the cyclothem are small, inornate forms, suggesting deeper, cooler water. The phosphate rich, black facies of the offshore shale represents cold, deep, dyaserobic (oxygen deficient) to anoxic (no oxygen) water. The depth of the water was below the photic zone (maximum penetration of sun light) and no algae was produced on the sea floor. Decaying algae and other organic matter provided both phosphate and carbon that resulted in the black shale that has a foetid odor. This environment provided an opportunity for many unusual fossils to become preserved as imprints and skeletons as they settled to the bottom of the sea. The black facies of the offshore shale is commonly succeeded by deposition of shale that is nearly a mirror image of the non-black portion of the offshore shale. These beds are followed by deposition of usually thick, coarsely crystalline regressive limestone that contains large, often highly ornamented fossils that suggest they lived in warm, shallow, well-oxygenated water. The regressive limestone may contain shoal deposits near its top and it may be weathered and show evidence of soil development. A new cyclothem begins at this time and the cycles have repeated themselves many times during the late Paleozoic in the midcontinent.
Pennsylvanian and Permian age fish remains found in Nebraska have been the subject of various researchers since about 1850. Joseph Leidy (1854); J. S. Newberry and A. H. Worthen (1866, 1870) described several species of teeth from shark-like fishes from the Coal Measures of Nebraska. O.W. St. John and A. H. Worthen(1875, 1883) completed two important studies on these fossils. Near the turn of the century, E. D. Cope (1871, 1875, 1877, 1883, 1889, 1891, 1894) described many late Paleozoic vertebrate fossils from the North American Midcontinent, including much Nebraska material. C. R. Eastman (1896, 1897, 1899, 1900, 1901, 1902a, 1902b, 1902c, 1902d, 1902e, 1903a, 1903b, 1904, and 1917) recorded many fossil fishes from the midcontinent. Eastman with and E. H. Barbour (1902) summarized the fish fauna from the late Paleozoic of Kansas and Nebraska. Research remained static until 1934 when A. S. Romer and H. J. Smith published the results of studies of Carboniferous dipnoans (lungfish). In more recent times, M. C. Hansen (1968), L. D. Martin (l969, 1972, C. R. Ossian (1974), and R. Zangerl and G. R. Case (1973), and J. Maisey (1981) have actively studied Pennsylvanian and Permian age fishes. Erom the late 1960’s and early 1970’s, W. D. White, William J. Rushlau, and Gerard R Case collected many of the fish fossils from the black shale facies in the midcontinent. Some of these finds are shown here. This page also illustrates some of the fish, teeth, fins, and other remains they have collected.
Orodont sharks are characterized by having long, slender eel-like bodies with very small fins (Zangerl, 1981). Some exceptional specimens have been collected from the deep water, black shale beds that were deposited in anoxic (oxygen free) environments that saved the carcasses of these Pennsylvanian giants from becoming disarticulated by scavengers or by the wave action of shallow water environments. Several more or less complete specimens of orodont sharks have been collected from fissile, black shale horizons in the upper Pennsylvanian of southeastern Nebraska. That orodont sharks became quite large is evidenced by an incomplete specimen from Indiana that measured over 3 m (9 feet) long. Several teeth that have been attributed to the genus Orodus have been found in the Pennsylvanian – Permian section of Nebraska. Orodus is a very long ranging genus, the oldest examples being found in rocks as old as Devonian.
Orodus? sp.
Symphysial tooth
Orodus? sp.
Agassizodus sp. cf. variabilis (Meek & Worthen)
Campodus may have been a plankton feeder, eating algae and tiny organisms that essentially floated and carried at will by the currents in the near surface ocean waters. Some individual Campodus may have grown to become some very large creatures. Its’ teeth do not have the sharp edges that would be suitable for tearing flesh and the tiny ridges across the crown of the tooth do not suggest it was suitable for crushing shells of invertebrates such as brachiopods. A more or less complete specimen in the University of Nebraska State Museum Collections that was collected by the late W. D. “Ted” White that is about one meter long is preserved in black shale, and its largest lateral teeth are about 15 mm wide. Some individual Campodus teeth also collected by Mr. White are over 100 mm wide. These large teeth suggest some very large fish, perhaps as long as 13 m (40 ft). The are also some “V-shaped” teeth that have also been attributed to the genus Agassizodus. Such teeth are called symphysials and they were positioned in the middle of the mouth at the plane of symmetry that extended the length of the fish.
Cladodus occidentalis [(Leidy) artist's reconstruction]
Cladodus teeth
Cladodus Weeping Water (artist's reconstruction)
Cladodus appears to have been a true predator. Cladodus had many “T-shaped” teeth with a large, central cusp, and smaller, paired lateral cusps. They appear to be designed to grasp and hold on to prey as well as to be able to tear flesh. Prey of cladodont sharks may have included cephalopods such as nautiloids and ammonoids, and at least one example of a coiled a coiled ammonoid with evidence of shark bites has been documented by Mapes and Hansen (Hansen and Mapes)? A specimen of conularid from the slightly younger Barnsdall Formation of Oklahoma also has bite marks that may have been made by a cladodont shark. Thus, large invertebrates, especially swimmers such as cephalopods, and smaller fish may have also been included in the diet of Cladodus.
Cladodont? Shark
Cladodus? sp.
Protacrodus sp.
Xenacanthus sp.
Petalodont teeth are compressed and usually elongated compared to other Pennsylvanian and Permian shark teeth. The crown and root are commonly about equal length and there are commonly distinct ridges on the lingual (inner) side of the tooth where the crown and root meet. Few petalodont teeth have been found associated with other fish parts or as preserved cartilaginous imprints in black shale. Thus, little is known about the morphology of the petalodont fishes.
Petalodus sp cf. destructor (Newberry & Worthen)
Janassa sp. cf. maxima (Eastman)
The teeth of Janassa are characterized by their “S-shaped” (sigmoid) outline when viewed laterally. Only a few examples of teeth attributable to Janassa have been found in Nebraska, but some more or less complete examples of janassiform fishes that superficially resemble skates or rays have been recovered from the Permian of Germany. Their teeth appear to be designed for crushing shells, and the stomach contents of specimens of Janassa bituminosa (Malzahn) from the Permian of Germany contained fragments of brachiopods, crinoids, foraminifers, and crabs.
- Serratodus? sp. (no image)
- Chomatodus sp.
Dentition in the pristodonts is reduced to a single tooth in the upper and lower jaw.
Peripristis “Ctenoptychius” semicircularis (Newberry and Worthen, 1866)
Pavement Teeth
Cochliodus sp. cf. contortus (Agassiz)
Cochliodus tooth (no image)
Deltodus sp.
?Sandalodus sp.
Paleoniscus? sp.
Chirodus? sp.
Miscellaneous Shark and Fish Remains
Shark SpinesCtenacanthus? sp.
“Physonemus” sp.
Listracanthus sp.
Petrodus sp.
Gastric residue spatter
Coprolites
Bite Marks
- Cope, E. D., 1871, Observations on the extinct batrachian fauna of the Carboniferous of Linton, Ohio. Proceedings of the American Philosophical Society, v. 12, p. 177.
- -----, 1875, Synopsis of the extinct batrachia from the Coal Measures. Report of the Geological Survey, Ohio, v. 2, p. 350 – 411.
- -----, 1877, Descriptions of extinct Vertebrata from the Permian and Triassic Formations of the United States: Proceedings of the American Philosophical Society, v. 17, p. 182 – 193.
- -----, 1883, Fourth contribution to the history of ther Permian formation in Texas: Proceedings of the American Philosophical Society, v. 20, p. 628 – 636.
- -----, 1889, Synopsis of the families of Vertebrata: American Naturalist, v. 23, p. 849 – 877.
- -----, 1891, On the characters of some Paleozoic fishes, I. On a new elasmobranch from the Permian, Styptobasis knightiana gen. Et sp. nov.: Proceedings of the U. S. National Museum, v. 14, p. 447.
- -----, 1894, The fossil vertebrates from the Fissure at Port Kennedy, Pennsylvania: Proceedings of the Academy of Natural Sciences of Philadelphia, p. 446 – 451.
- Eastman, C. R., 1896, Remarks on Petalodus allegheniensis Leidy: Journal of Geology, v. 4, p. 174 – 176.
- -----, 1897, On the character of Macropetalichthys: American Naturalist, v. 31, p. 493 – 499.
- -----, 1899, Some new American Fossil Fishes: Science, v. 9, p. 642 – 643.
- -----, 1900, Karpinsky’s genus Helicoprion: a review: American Naturalist, v. 34, p. 579.
- -----, 1901, On Campodus, Edestus, Helicoprion, Acanthodes, and other Permo-Carboniferous sharks [abstract]: Science, new series, v. 14, p. 795.
- -----, 1902a, The Carboniferous fish fauna of Mazon Creek, Illinois: Journal of Geology, v. 10, p. 535 – 541.
- -----, 1902b, Campyloprion, a new form of Edestus-like dentition: Geological Magazine, v. 4, no. 9, p. 148 – 152.
- -----, 1902c, On the genus Peripristis St. John: Geological Magazine, v. 4, no. 9, p. 388 – 391.
- Romer, A. S., and Smith, H. J., 1934, American Carboniferous dipnoans: Journal of Geology, v. 42, p. 700 - 719.
- -----, 1902d, Some Carboniferous cestraciont and acanthodian sharks: Harvard College, Museum of Comparative Zoology Bulletin, v. 39, p. 55 – 99.
- -----, 1902e, Some hitherto unpublished observations of Orestes S. John on Paleozoic fishes: American Naturalist, v. 36, p. 653 – 659.
- -----, 1902f, Notice of interesting new forms of Carboniferous fish remains: American Naturalist, v. 36, p. 849 – 854.
- -----, 1903a, Carboniferous fishes of the central western states: Harvard Collections, Museum of Comparative Zoology Bulletin, v. 39, p. 163 – 226.
- -----, 1903b, On the nature of Edestus and related forms: Mark Anniversary Volume, Harvard University, p. 279 – 289.
- -----, 1904, A brief general account of fossil fishes: New Jersey Geological Survey, Annual Report, p. 27 – 66.
- -----, 1917, Fossil fishes in the collection of the United States National Museum: Proceedings of the U. S. National Museum, v. 52, no. 2177, p. 235 – 304.
- Eastman, C. R., and Barbour, E. H., 1902, Synopsis of the Missourian and Permo-Carboniferous fish fauna of Kansas and Nebraska [abstract] : Science, new series, v. 16, p. 266 – 267.
- Hansen, M. C., 1968, the Upper Paleozoic genus Petalodus (Bradyodonti) from North America [abstract]: Nebraska Academy of Sciences Proceedings, 78th Annual Meeting, p. 19 – 20.
- -----, 1977, Origin of phosphatic black shale in Pennsylvanian cyclothems of Mid-Continent North America: American Association of Petroleum Geologists Bulletin 61, no. 5, p. 1045-1068.
- Heckel, P. H., and Baesemann, J. F., 1975, Environmental interpretation of conodont distribution in Upper Pennsylvanian (Missourian) megacyclothems in eastern Kansas: American Association of Petroloeum Geologists Bulletin, v. 59, no. 3, p. 486-509.
- Leidy, J., 1857, Notices of some remains of extinct fishes: Proceedings of the Academy of Natural Sciences of Philadelphia, 1857:167-168.
- Maisey, J., 1983, Some Pennsylvanian chondrichthyian spines from Nebraska: Transactions of the Nebraska Academy of Sciences, v. 11, p. 81 – 84.
- Martin, L. D., 1969, A vertebrate assemblage from the early Permian of Nebraska [abstract]: Nebraska Academy of Sciences Proceedings, 79th Annual Meeting, p. 26 – 27.
- -----, 1972, Coelocanth fishes from the Pennsylvanian and Permian of Nebraska and Kansas: Nebraska Acedemy of Sciences Proceedings, 82nd Annual Meeging, p. 40, 41.
- Newberry, J. S., and Worthen, A. H., 1866, Geological Survey of Illinois. Paleontology of Illinois, Section 1, Descriptions of new species of vertebrates, mainly from the sub-Carboniferous Limestone and Coal Measures of Illinois, v. 2, p. 1 – 141.
- -----, 1870, Description of fossil vertebrates: Geological Survey of Illinois, v. 4, p. 347 – 374.
- Ossian, C. R., 1974, Paleontology, paleobotany and facies characteristics of a Pennsylvanian delta in southeastern Nebraska: University of Texas, unpublished phD dissertation, 393 p.
- Romer, A. S., and Smith, H. J., 1934, American Carboniferous dipnoans: Journal of Geology, v. 42, p. 700 - 719.
- St. John, O. W., and Worthen, A. H., 1875, Description of fossil fishes: Illinois Geological Survey, v. 6, p. 245 – 488.
- -----, 1883. Description of fossil fishes: Illinois Geological Survey, v. 7, p. 55 – 264.
- Zangerl, R., and Case, G. R., 1973, Iniopterygia, a new order of Chondrichthyian fishes from the Pennsylvanian of North America: Fieldiana Geology Memoirs, 67 p.
For information about Nebraska's Invertebrate Fossils, please see our Range and Distribution of Nebraska's Invertebrate Fossils, For information about vertebrate paleontology, visit Discover Your Nebraska County Fossils, by Greg Brown, University of Nebraska State Museum.
Fossil Fish from Nebraska was compiled by
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Roger K. Pabian Research Geologist, Emeritus 610 Hardin Hall 3310 Holdrege Streets University of Nebraska-Lincoln Lincoln, Nebraska 68583-0996 Phone 402-472-7564 Fax 402-472-2946 rpabian1@unl.edu |
