A Brief History of Fossil Fish Collecting in Kansas
Though not from Kansas, the first known fossil fish from the Niobrara Chalk was collected by the Lewis and Clark expedition in August of 1804 from the bank of the Missouri River in what is now Harrison County, Iowa. The fish jaw (ANSP 55 16) is currently in the collection of the Academy of Natural Sciences of Philadelphia and is the only fossil specimen surviving from that expedition (Spamer et al., 2000). The history of this fossil is somewhat confused, however, because it was originally misidentified by Dr. Richard Harlan (1824) as the jaw of an "Enalio Saurian" (a marine lizard thought to be somewhat like ichthyosaurs and plesiosaurs). Harlan described it and gave it the name Saurocephalus lanci-formis. It wasn't until six years later when Isaac Hays (1830) described a similar species of Cretaceous fish (Saurodon leanus) from New Jersey that the mistake was officially noticed and corrected. Leidy (1856, p. 3 0 2) noted that the Saurocephalus specimen was a fragment of a "maxillary bone with teeth of a peculiar genus of sphyraenoid fishes from the Cretaceous formation of the Upper Missouri." This group of fossil fishes would continue to give other paleontologists classification problems as more discoveries were made.
Joseph Leidy (1859) described a dorsal spine (Xystracanthus) and two teeth of two different species of Paleozoic sharks (Clado-dus and Petalodus) found in eastern Kansas two years before Kansas became a state. The teeth had been discovered in 1 858 by the U.S. Geological Survey expedition (Meek and Hayden) while traveling through Kansas during their exploration of several Midwestern states. This paper is important because it is the first description of vertebrate fossils from Kansas and is one of the first descriptions of North American vertebrates from the Permian.
Professor Benjamin Mudge (1 81 7- 1879) was one of the first paleontologists in Kansas. He began collecting fossils in the central and western parts of the state several years before Marsh and Cope arrived. As was customary for the times, he sent many of his specimens to the scientists "back East" for identification. For the most part, he was communicating with E. D. Cope during the late 1860s and early 1870s. In an 1 870 letter (Williston, 1 898, pp. 29-30),
Cope complimented Mudge on the scientific value of the material he had sent. In fact, many of the new species of fish and mosasaurs described by Cope were from the specimens sent to him by Mudge (Everhart, 2002) . During his only trip to Kansas in late 1871, Cope (1872a) visited Mudge in Manhattan, Kansas, and examined his collection. By then, however, Mudge had begun sending some specimens, including the remains of the first known toothed bird (Ichthyornis) to Cope's rival, O. C. Marsh (see Chapter 11). In 1874 he began collecting fossils solely for O. C. Marsh and Yale College. Unfortunately, Mudge died in 1879.
In late 1867, Dr. Theophilus Turner, the assistant surgeon assigned to Fort Wallace in western Kansas, also began communicating with Cope about his discovery of a huge plesiosaur. Cope (1868) reported on finding the remains (scales, vertebrae, and teeth) of six species of fish, including Enchodus, that he believed to be stomach contents from the new plesiosaur (Elasmosaurus platyums) found by Turner (See Chapter 7). When I examined the remains that had been collected by Turner (ANSP 10081) in 2002, there were still fish scales, teeth, and bone fragments visible in some of the concretionary matrix that was associated with the plesiosaur bones. However, I consider them more likely to be the normal detritus that might be expected to accumulate on the sea bottom rather than evidence of the plesiosaur's last meal. In any case, they did provide evidence of several species of fish that were living at the same time (middle Campanian) as the elasmosaur.
In addition to performing his military duties during the late 1860s, Dr. George M. Sternberg (older brother of Charles H. Sternberg) collected and sent fossils from western Kansas to the Army Medical Museum in Washington, D. C. The fossils were then forwarded to the Smithsonian Institution, where they were more readily available for study by the paleontologists of the day. Leidy (1870) described a new species of fish (Xiphactinus audax) from a large (40 cm [16 in.]) fragment of a pectoral fin ray (USNM 52) that Dr. Sternberg had found. After examining the same specimen, however, Cope (1871) disagreed with his mentor and renamed it Saurocephalus audax Leidy. Apparently, Cope's name change was not recognized by anyone else. Later that year, Cope (1872b) described a "new" genus and species from the remains of several relatively complete specimens of fish he had found near Fort Wallace on his visit to western Kansas. He called the fish Portheus molossus without recognizing that it was the same species that Leidy had named almost two years earlier. It is not known if Leidy recognized that it was the same species or not. Almost thirty years later, O. P. Hay (189 8) published a short note in Science suggesting that Xiphactinus Leidy was the correct genus, but by then it was too late. Portheus Cope was too well established to be banished that easily. Even the prominent paleontologist H. F. Osborn (1904) was unaware or, even worse, ignored Leidy's name in favor of Cope's when he wrote about a newly acquired "Portheus molassus" specimen (AMNH 322 1 99) at the American Museum of Natural His tory. Since that time, even though it is widely known to be a junior synonym of Xiphactinus audax Leidy, the name Portheus molossus Cope is much better recognized, and many museum collections still have their specimens mislabeled.
There is one further unusual twist to this story. Xiphactinus (Polygonodon) vetus is a sister species of X. audax that was named by Leidy (1856) on the basis of teeth found in the Cretaceous of New Jersey. In naming them, Leidy believed that the teeth were those of a reptile (Schwimmer et al., 1997) and apparently didn't consider that they might be from a large fish. So if you really wanted to confuse the issue, the scientific name of the big fish found in the Kansas chalk should be "Polygonodon" audax Leidy 1870.1 don't think that is likely to happen, however.
Following the discovery of Elasmosaurus platyurus in 186 7 and the first Kansas mosasaur, Tylosaurus proriger, in 1868, Kansas quickly became a popular place to search for fossils. In 1870, O. C. Marsh mounted the first of four organized fossil-collecting trips to the western states, including Kansas, with his students. Although they spent less than two weeks in Kansas, the Yale College scientific expedition of 1870 was an immediate success, recovering dozens of specimens, including several mosasaurs, part of the wing of a previously unknown giant pterodactyl from Kansas (Marsh, 1871), and even a fragment of an unknown bird (Hesper-ornis). Strangely, Marsh was not at all interested in fish (Shor, 1971, p. 78) and instructed his field workers to ignore them. This allowed his rival, E. D. Cope, to describe and name many of the species from the Smoky Hill Chalk. Marsh's instructions may have been the source of a statement by B. F. Mudge (1876, p. 216) , who wrote, "the least interesting are the fish, which have, however, given many new species and some new genera. The small ones are near entire, but the larger are represented by well-preserved portions of the skeletons." Years earlier, Mudge had collected a number of fish specimens for Cope (see Cope, 1872a) and Cope, in turn, had credited Mudge with the discovery of a number of new species. After being hired by Marsh, however, Mudge's collecting was focused more on toothed birds, pteranodons, and marine reptiles. Chris Bennett (pers. comm., 2004) indicated that when he examined the Yale fish collection in the 1980s, "there were still unopened packages from Mudge."
Cope (1872b) published a list of the families of fishes found in the "Cretaceous Formation of Kansas" that included most of the common varieties that we are familiar with today, even though only limited collections had been made from the chalk at that time. Many of Cope's "species" were described from fragmentary remains or single teeth, and the family names would be changed again and again as more complete specimens were found. Cope (ibid, p. 357) also noted that twenty-four species had been described from the Kansas chalk and that the same genera had been found in the chalk of Europe (see Table 5.1 for an updated listing of fishes from the Smoky Hill Chalk). His list included:
1. Saurodontidae (Ichthyodectidae): Portheus (Xiphactinus), Ichthyodectes, Gillicus, and Saurocephalus
2. Pachyrhizodontidae: Pachyrhizodus and Empo (Cimolichthys)
3. Stratodontidae: Stratodus, Enchodus, and Apsopelix
The history of collecting, identifying, describing, and naming the many species of fish that have been found in the chalk is confusing at best. In most cases, the early paleontologists involved were working with scraps and seldom had the luxury of seeing even a large portion of the complete fish. Rather than try to relate the history of the discovery of each genus, I will go into the details of those I think are the more interesting ones.
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