Pycnodonts were small to medium-sized, deep-bodied bony fish with round, flattened teeth that are well adapted for crushing food items. While it is possible that these fish "nibbled" on the invertebrates and algal growths (epifauna) that were attached to inoceramid shells at the bottom of the Western Interior Sea, it is far more likely that they preferred shallower water nearer to shore (Manning, pers. comm., 2004). They may have been much like the modern parrot fish in that regard. (More information here) It is quite possible that the scattered remains that we find in the Smoky Hill Chalk are from individuals that strayed too far from the shore and died in deep water.
Cragin (Colorado College Studies, V, 1894) described Macromesodon abrasus (Cragin) based on isolated teeth taken from his "No. 3 of the Belvidere section," of the Kiowa Shale, Lower Cretaceous. Williston (Kan. Univ. Quart. IX, No. 2, 1900a, pp. 28-29 [see also Williston, 1900b]) reported a fragment of the left lower jaw containing two rows of teeth of Coelodus brownii Cope and a fragment of the lower right jaw of Coelodus stantoni Williston from the Kiowa Shales of Kansas. Hibbard and Graffham (1941) wrote: "The remains of Pycnodont fish have rarely been found in the Cretaceous of Kansas." While they are no longer considered to be rare, they are certainly uncommon discoveries.
LEFT: (Click to
enlarge) Fragments of pycnodont tooth plates from the Kiowa Shale (Early Cretaceous,
Albian age), of south-central Kansas (Adapted from Williston 1900b, Plate XXIV): 11)
Right splenial of Coelodus stantoni Williston, and; 12) Left splenial of Coelodus
brownii Cope, Kiowa County. Note that "Coelodus" brownii and "Coelodus" stantoni are probably not closely related to the type species of Coelodus, C. saturnus, from the Turonian-Santonian of Slovenia (see Poyato-A. & Wenz, 2002, p. 8). It is difficult to accurately identify species from the isolated tooth plates that are most commonly collected. RIGHT: A single tooth from a Coelodus sp. splenial in occlusal, lateral and basal views. Kiowa Shale, Clark County, KS. Scale = mm. |
You can now download a copy of this early article on Kansas sharks and pycnodonts by S.W. Williston - Provided by the Kansas Geological Survey:
Williston, S. W. 1900. Cretaceous fishes: Selachians and Pycnodonts. University Geological Survey Kansas VI pp. 237-256, with pls.
Systematic Paleontology: Class Osteichthyes Actinopterygii Neopterygii Pycnodontiformes |
Hibbard and Graffham (1941) described a new species of pycnodont ("Pycnomicrodon" kansasensis - KUVP 1019) from the Niobrara of Rooks County. However the genus name was preoccupied, and they changed the genus name to Micropycnodon (Hibbard and Graffham, 1945).
Over the last hundred years, a relatively small number pycnodont specimens have been collected from Cretaceous rocks in Kansas, ranging from the Albian Kiowa Shale (Early Cretaceous) through at least the end of the Coniacian in the Smoky Hill Chalk (See Stewart, 1990). Most of these specimens consist of only a tooth bearing element from the skull. This page will illustrate a variety of specimens found in Kansas, beginning with the Early Cretaceous.
Albian (Early Cretaceous) Kiowa Shale:
LEFT AND RIGHT: Two views of a partial vomerine toothplate (KUVP 16197), possibly from a juvenile pycnodont (Kiowa Shale of Clark County, Kansas). Collected by Orville Bonner in 1969 - possibly Coelodus brownii. (Scale = mm) | ||
LEFT: A fragment of a pycnodont vomer (KUVP 16188) from the Kiowa
Shale of Clark County, Kansas. (Scale = mm) RIGHT: A second pycnodont vomer fragment (KUVP 17408), also from the Kiowa Shale of Clark County, Kansas. (Scale = mm) Note that the row of largest teeth is on the midline of the roof of the mouth, and supported above by the vomer bone. |
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LEFT: Three views of a single tooth crown (Coelodus sp.),
probably vomerine, that I collected from near the base of the Kiowa Shale (Albian)
in Kiowa County, KS in 2002. (Scale = mm) RIGHT: A weathered, partial right pre-articular toothplate, with anterior at left, and lateral at top of Coelodus stantoni in the collection of the Sternberg Museum (FHSM VP-7280). It is missing both the smaller medial and lateral teeth. (Scale = mm) |
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LEFT: Close-up of a small pycnodont tooth crown discovered in a
shelly mudstone matrix in the Kiowa Shale, about 6 m above the base, in Kiowa County,
Kansas, July 14, 2006. The greenish-white shapes around the tooth are lichens on the
surface of the rock. The whitish color of the tooth crown is due to weathering and
exposure to sunlight. RIGHT: A second pycnodont tooth (circled) in another piece of shelly mudstone from the Kiowa Shale, Kiowa County, Kansas. There are several other small shark and fish teeth visible in this piece of matrix. (Scale = mm) |
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LEFT: Three isolated toothplate teeth collected from the Kiowa
Shale in McPherson County, Kansas. Note the evidence of wear on the tooth in the upper
right of the picture. (Scale = mm) RIGHT: Three isolated pycnodont and two gar (Lepidotes sp.) teeth from the Kiowa Shale of McPherson County, Kansas. Pycnodont teeth were among the most common vertebrate remains found at this site: (See shark remains from the Kiowa Shale here.. near bottom of page) (Scale = mm)
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Middle Cenomanian (Late Cretaceous) Upper Dakota Sandstone (at the transition to basal Graneros Shale)
Middle Cenomanian (Late Cretaceous) Basal Lincoln Limestone Member, Greenhorn Limestone Formation
LEFT and RIGHT: Two views of a pycnodont partial juvenile right prearticular toothplate (FHSM VP-15548) collected in 2003 by Keith Ewell from the basal Lincoln Limestone Member of the Greenhorn Limestone, in Russell County, Kansas (probably Micropycnodon kansasensis). (Scale = mm) | ||
LEFT: A very large pycnodont toothplate from a roadcut south of
Belleville, Kansas (Republic County). The specimen is probably from the upper Lincoln
Member of the Greenhorn Limestone (FHSM VP-16865). RIGHT: The same specimen after cleaning. Based on size alone, this toothplate is probably from a larger pycnodontid fish like Hadrodus priscus. Click here for a picture of an incisor tooth from Hadrodus sp. (Fairport Chalk Member, Carlile Shale) - FHSM VP-16865 |
Middle Turonian (Late Cretaceous) Carlile Shale
LEFT: An occlusal view of the type specimen of Coelodus
streckeri (KUVP 946) from the Carlile Shale of Russell County, as figured by Hibbard
(1939). (Photo of actual specimen) (Anterior view) RIGHT: The type specimen of Coelodus streckeri (KUVP 946) in left lateral view, as figured by Hibbard (1939). (Photo of specimen) Both figures modified from: Hibbard, C.W. 1939. A new pycnodont fish from the Upper Cretaceous of Russell County, Kansas. Quarterly Bulletin University of Kansas 26: 373-375, 1 pl. |
Middle Turonian (Late Cretaceous) Blue Hill Shale Member of the Carlile Shale
Late Coniacian (Late Cretaceous) Smoky Hill Chalk Member of the Niobrara Chalk
There is some confusion regarding the stratigraphic occurrence of the type specimen and a more complete specimen (KUVP 7030) shown below. While Hibbard & Graffham (1941, p. 72) noted that the type specimen was from the Niobrara, this could mean the Fort Hays Limestone or the Smoky Hill Chalk. However, Dunkle & Hibbard (1946, p. 162) said the type, and a new specimen (KUVP 7030), was from the basal Ft. Hays Limestone Member, basal Niobrara Formation. This was maintained by both Schultze, et al. (1982, p. 22) and Stewart (1990, p. 21). The type locality is now beneath Webster Reservoir (Stewart, 1990, p. 21) and is no longer accessible. Vertebrate fossils, especially articulated ones, are usually rare in the Fort Hays but may be more common near the base (pers. obs.). My examination of KUVP 7030 indicates that the matrix was more like the chalk than the Fort Hays Limestone, but again, much of the basal Fort Hays is a chalky limestone. In any case, the species does occur in the lower part (late Coniacian) of the Smoky Hill Chalk, and would also be expected to be found in the underlying Fort Hays Limestone. The two specimens in the lower photos are definitely from the Smoky Hill Chalk.
LEFT: Skull and tooth plate elements of the type specimen
of Micropycnodon kansasensis (KUVP 1019) in the collection of the University of
Kansas Museum of Natural History. RIGHT: The tooth bearing vomer from the roof of the mouth of the same fish, attached to the specimen at left. |
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LEFT: KUVP 7030 (Micropycnodon kansasensis) is
probably the most complete specimen of a pycnodont ever found in Kansas. It was collected
and prepared by by G. F. Sternberg in Trego Co. Kansas about 1935 and then described by
Dunkle and Hibbard (1946). Anterior is to the left, dorsal is to the top in this picture. (Scale
= mm) RIGHT: Photograph (circa 1935) of the KUVP 7030 specimen by G.F. Sternberg. Note that Sternberg had originally plastered the lower (right) side of the fish; the plaster was later removed from the right side of the skull to allow further study, probably by Dunkle and Hibbard. |
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LEFT AND RIGHT: Details of the lower jaws of KUVP 7030. Micropycnodon kansasensis. (Scale = mm) | ||
LEFT: KUVP 75043 - Collected from Rooks County near the
contact between the Fort Hays Limestone and Smoky Hill Chalk. RIGHT: A left prearticular toothplate (FHSM VP-15732) of a juvenile Micropycnodon kansasensis collected by Keith Ewell in 2004 from below MU2 in southwestern Trego County. The white color of some of the teeth indicates oxidation of the enamel due to weathering. (Scale = mm) |
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LEFT: A right prearticular tooth plate (FHSM VP-16584)
collected by Pam Everhart from southeastern Gove County in 1991. (Scale = mm).
This specimen occurred near marker unit 4 (Late Coniacian). (New picture 1) (New # 2) RIGHT: A small fragment of a pycnodont toothplate (private collection) compared to FHSM VP-16584. |
About Hadrodus: (Earl Manning, pers. comm. 2004) There are several things you can say about Hadrodus. Although it's not a pycnodontiform (Poyato-Ariza, F.J., and S. Wenz, 2002), it is very likely closely related to them, as shown by its deep-bodied form (seen in a partially-described Alabama specimen), the increased number and enlarged size of the vomerine and prearticular teeth, and the incisor-like anterior teeth (they're more like human incisors in pycnodonts, not as broad as in Hadrodus). Unlike pycnodontiform toothplate teeth, the teeth of Hadrodus are not arranged in regular rows, nor are some teeth especially enlarged and elongate. Hadrodus doesn't really have regular toothplates, the way pycnodonts do. The mandibular symphysis is oriented differently in the two taxa - it's nearly vertical, and anteriormost in Hadrodus, but nearly horizontal and largely medial in pycnodonts. Thurmond is probably correct to place Hadrodus in a separate family, the Hadrodontidae Thurmond, in Thurmond and Jones (1981, p. 82). Both likely ate hard-shelled prey. Both Hadrodus and the pycnodonts probably derive from the Late Jurassic/Early Cretaceous lepidotids, which were also deep-bodied bony fish, and had enlarged oral cavity teeth. The type specimen of the type species, H. priscus Leidy, 1858 (figured in Leidy, 1873, pl. 19, figs. 17-20) is an adult left premaxilla, likely from the Late Santonian of northeast Mississippi. Adult specimens have been found in the deep water chalks of Alabama (Applegate, 1970 [partly under the name "Propenser"]; Thurmond & Jones, 1981, pp. 82-3; and Bell, 1986 - the last a partially-described nearly complete skeleton) and Kansas (a lower jaw collected in Logan Co. by the Marsh party in 1872, and described by Gregory, 1950). It is also known from far more abundant, and far smaller, isolated juvenile teeth (ant., oral cavity, and distinctive hook-like pharyngeal teeth [sometimes called "Ancistrodon" or "Stephanodus"] - which are associated with the oral cavity teeth in some Alabama specimens [Thurmond & Jones, 1981; and Bell, 1986]), which are almost always found in far shallower marine water (Manning and Dockery, 1992, p. 12, pl. 9, figs. 5-6). How the comb-like pharyngeal tooth structure (Thurmond and Jones, 1981, fig. 39, nos. 1,2, 5, and 6) was used is uncertain, but it may have strained out small food particles from crushed prey, going down the throat. It appears that the young lived in protected inner waters, while the adults lived in deeper, open water. On the Gulf and Atlantic Coastal Plain, Hadrodus isolated teeth, especially the small juvenile teeth, are known from Late Cretaceous marine beds from Texas to New Jersey. In Kansas, Hadrodus has a long range (nearly as long as its Late Cretaceous beds), from the Middle Cenomanian up. Dakota / lower Graneros shales to the Early Campanian upper Smoky Hill Chalk. They are commonly found as juveniles in shallow-water deposits, and rare adults in deep-water deposits. |
LEFT: FHSM VP-14006 - An adult Hadrodus upper
second incisor from the Carlile Shale (probably Blue Hill Shale Member).
(Scale = mm) RIGHT: The same incisor, multiple views. |
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LEFT: Multiple views of another incisor from the Blue
Hill Shale Member of Mitchell County, KS. (Private collection) RIGHT: The same adult incisor and 4 large pharyngeal teeth (unassociated) from the Blue Hill Shale Member of Mitchell County, KS. (Private collection) |
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Bell (1986) described a reasonably complete Hadrodus specimen (RMM 1950) that he
had collected from the Mooreville Chalk of Greene County, Alabama in 1979. The remains
were identified by Bell as Hadrodus hewletti. I was able to examine and
photography the specimen in late 2007. These pictures are similar to the line drawings
published as figures in Bell (1986). LEFT: Lateral view of the right splenial and dentary. RIGHT:Lateral view of the right premaxilla. |
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LEFT:Dorsal view of neurocranium. RIGHT: Pharyngeal teeth - Gill rakers are HERE |
Other Oceans of Kansas webpages on Late Cretaceous fish:
Field Guide to Sharks and Bony Fish of the Smoky Hill Chalk
Sharks:
Bony Fish
Plethodids:
REFERENCES:
Bell, G. L., Jr. 1986. A pycnodont fish from the upper Cretaceous of Alabama. Journal of Paleontology 60(5):1120-1126, 2 figs.
Everhart, M. J. 2007. Remains of a pycnodont fish (Actinopterygii: Pycnodontiformes) in a coprolite; An upper record of Micropycnodon kansasensis in the Smoky Hill Chalk, western Kansas. Kansas Academy of Science, Transactions 110(1/2): 35-43.
Everhart, M. J., P. A. Everhart and K. Ewell. 2004. A marine ichthyofauna from the Upper Dakota Sandstone (Late Cretaceous). Abstracts of oral presentations and posters, Joint Annual Meeting of the Kansas and Missouri Academies of Science, p. 48.
Everhart, M. J., P. Everhart, E. M. Manning, and D. E. Hattin. 2003. A Middle Turonian marine fish fauna from the Upper Blue Hill Shale Member, Carlile Shale, of north central Kansas. Journal of Vertebrate Paleontology, Volume 23 (Supplement to Number 3): 49A.(Abstract)
Dunkle, D.H. and Hibbard, C.W. 1946. Some comments upon the structure of a pycnodontid fish from the upper Cretaceous of Kansas. University Kansas Science Bulletin 31 (8):161-181, pt. 1.
Gidley, J. W. 1913. Some new American pycnodont fishes. Proc. U. S. National Museum, No. 2036, 46:445-449.
Gregory, J. T. 1950. A large pycnodont from the Niobrara Chalk. Postilla (5):10 p. (Hadrodus)
Hattin, D. E. 1962. Stratigraphy of the Carlile Shale (Upper Cretaceous) in Kansas. State Geological Survey of Kansas, Bulletin 156, (University of Kansas pub.) 155 p. 2 pl.
Hibbard, C. W. 1939. A new pycnodont fish from the Upper Cretaceous of Russell County, Kansas. Quarterly Bulletin University of Kansas 26: 373-375, 1 pl.
Hibbard, C. W. and A. Graffham. 1941. A new pycnodont fish from the Upper Cretaceous of Rooks County, Kansas. Quarterly Bulletin University of Kansas 27:71-77, 1 fig., 1 pl.
Hibbard, C. W. and A. Graffham. 1945. Micropycnodon, new name for Pycnomicrodon Hibbard and Graffham not Hay. Kansas Academy of Science, Transactions 47(3):404.
Hussakof, L. 1947. A new pycnodont fish from the Cretaceous of Arkansas. Fieldiana - Geology 10(4):23-27.
Manning, E. M. and D. T. Dockery III. 1992. A guide to the Frankstown vertebrate fossil locality (upper Cretaceous), Prentiss County, Mississippi. Mississippi Department Environmental Quality, Office of Geology, Circular 4, 43 p. 2 pl.
Poyato-Ariza, F.J. and S. Wenz. 2002. A new insight into pycnodontiform fishes. Geodiversitas, 24(1):139-248. (PDF File)
Shimada, K. and Everhart, M.J. 2009. First record of Anomoeodus (Osteichthyes: Pycnodontiformes) from the Upper Cretaceous Niobrara Chalk of western Kansas. Kansas Academy of Science, Transactions 112(1/2):98-102.
Stewart, J. D. 1990. Niobrara Formation vertebrate stratigraphy, pages 19-30, In Bennett, S. C. (ed.), Niobrara Chalk Excursion Guidebook, The University of Kansas Museum of Natural History and the Kansas Geological Survey.
Thurmond, J. T. and D. E. Jones. 1981. Fossil vertebrates of Alabama. University of Alabama Press. Tuscaloosa, ix + 244 p., 88 text figs. (Family Hadrodidae)
Williston, S. W. 1900a. Some fish teeth from the Kansas Cretaceous. Kansas University Quarterly 9( 2):28-29.
Williston, S. W. 1900. Cretaceous fishes [of Kansas]. Selachians and Pycnodonts. University Geological Survey Kansas VI pp. 237-256, with pls.
Zielinski, S. L. 1994. First report of Pycnodontidae (Osteichthyes) from the Blue Hill Shale Member of the Carlile Shale (Upper Cretaceous; Middle Turonian), Ellis County, Kansas. Kansas Academy of Science, Abstracts 13(44).