Dakotasuchus kingi  

and other crocodiles from Kansas 

Life along the shores of the Late Cretaceous Western Interior Sea 

Copyright ?2011-2016 by Mike Everhart 

Page created 05/10/2011 - Last updated 12/30/2016

  

  

  

  

LEFT: Primitive toothed birds called Ichthyornis dispar rest near the large crocodile Deinosuchus while a herd of hadrosaurs (Claosaurus agilis Marsh) passes by in the background  in this paleo-life art by Doug Henderson. Copyright ?Doug Henderson; used with permission of Doug Henderson. While Deinosuchus remains have not yet been found in Kansas , another similar but smaller crocodile called Dakotasuchus kingi is found here.  See David Schwimmer's book, "King of the Crocodylians" for more information on Deinosuchus.

The remains of Cretaceous crocodiles are rare in Kansas, mostly because much of the state was completely underwater much of the time, but some remains have been found here. The first one, Hyposaurus vebbii, was described from a single cervical vertebra recovered during the construction of a water well in the Dakota Sandstone near Brookville, Kansas. Most of the rest are known only from single bones, teeth or dermal scutes.  The only reasonably complete specimen is that of Dakotasuchus kingi, discovered by a geologist (A. Wheeler Jones) around 1910 in the Dakota Formation west of Salina, Kansas. Crocodile remains occur in the Kiowa Formation (Albian, Early Cretaceous) and the Dakota Formation (Cenomanian, Late Cretaceous). Both formations were deposited in shallow, near-shore environments. Lane (1946) reported that the only known crocodile specimens from Kansas were Cretaceous in age. However, Liggett (1997) has since reported finding crocodile remains (scutes and teeth)  in Tertiary deposits in southwest Kansas.

LEFT: E.D. Cope (1872, 1875) reported the first crocodile from Kansas, Hyposaurus vebbii, based on a single cervical vertebra recovered from from a well being dug in the Dakota Formation near Brookville, Kansas. It was collected and sent to him by a friend, William Webb of Topeka, KS., and named in his honor. 

Cope's (1872, repeated in Williston 1898) description of the vertebra:  揂n anterior cervical vertebra presents the following characteristics. It is that one in which the parapophysis occupies a position opposite the lower third of the vertical diameter. Its centrum is stout in form; the articular faces but little concave; the posterior a little more so than the anterior. The anterior is almost regularly hexagonal; the posterior subround, a little deeper than wide. The inferior surface possesses a strong, obtuse, median carina, which disappears in front of the posterior margin. Anteriorly, it terminates in a short, obtuse hypapophysis. The suture of the neural arch is very coarse. Surface of the bone smooth. ?As compared with the H. rogersii, of the New Jersey Cretaceous, this vertebra is shorter and stouter, and the extremities less concave; the suture for the neural spine is much coarser. This Crocodile was discovered in a bluish stratum, encountered in digging a well in Brookville , Kan. ?See also Everhart  (2016) for additional information

LEFT: Williston (1894)  reported a crocodile vertebra from the Kiowa Formatione near Ashland, in Clark County, Kansas. Although he provisionally attributed it to Cope's Hyposaurus, he noted several differences. While crocodile teeth and scutes have been reported from the Kiowa Shale in McPherson County (see below and Beamon, 1999), it is possible that this specimen is actually the vertebra of a plesiosaur. Originally numbered KUVP 829, the specimen is now curated as KUVP 66331.  

Williston's (1894, 1898) description: "A single vertebra, wanting the neural arch, but otherwise well preserved, I refer somewhat doubtfully to Hyposaurus or a closely allied form. It has the articular surfaces nearly flat, with the rims sharp; the body is gently concave on the sides and below, from in front back, and with stri?near each rim for about half an inch. The surface elsewhere is smooth and even, without venous foramina. A transverse section through the middle would give the greater part of an elliptical figure, with the lower side somewhat flattened. Only the base of the pedicels is present, and there is no indication of a sutural union. Springing from them, or possibly from the body itself produced above to meet the arch, there is, on each side, a stout transverse process, the base only of which is present, but which appears to be short. In shape and appearance the centrum agrees well with one of Hyposaurus rogersii, from New Jersey , except in its more cylindrical shape.?o:p> 

Dakotasuchus kingi

Dakotasuchus kingi was described  by Mehl (1941; see also Lane 1946) from the Dakota Formation from "west of Salina. The specimen was last reported (1946) to be in the collection of Kansas Wesleyan University of Salina, Kansas. The current whereabouts of the specimen is unknown. A second specimen (a single scute; KUVP 9971) was reported by Vaughn (1956) from along the Smoky Hill River in Ellsworth County. It came from either the upper Kiowa or lower Dakota formations.

Mehl was able to make a cast of the last exposed dorsal vertebra;

LEFT: Dakotasuchus kingi Mehl. A-C  anterior, left lateral, and posterior views respectively of the last dorsal vertebra. (Mehl, 1941, Figure 1)

LEFT: Dakotasuchus kingi Mehl. Diagrammatic figures of pelvic girdle and ventral ribs. A. ventral view of pelvis, ischia foreshortened and ilia omitted, showing the relationship of 損ubic guard?and the position of ventral ribs. B. left lateral view of pelvis to show development of sacral ribs and pubis. (Mehl, 1941, Figure 3)
LEFT: Dakotasuchus kingi Mehl. A-C lateral views of right scapula, right coracoid, and direct posterior view of right scapula and coracoid respectively.  (Mehl, 1941, Figure 2) 
LEFT: Dakotasuchus kingi Mehl. Sketches showing details of dorsal and ventral armor. A. left lateral view of dorsal plates (anterior end toward the top) with underlap indicated by dotted outlines. B.  arrangement of plates of ventral shield (anterior end toward the top) with transverse section, C, at mid-length. D, E, and F are cross sections of plates 1, 9, and 18 respectively, of the dorsal shield.  (Mehl, 1941, Plate II) 
LEFT: Dakotasuchus kingi Mehl. Photographs of the concretion containing the type material of the genus and species. A. dorsal view showing the impression and some of the plates of the dorsal armor. B. ventral view showing the impression of the ventral shield and parts of pectoral and pelvic girdles. In each case the anterior end is up. (Mehl, 1941, Plate III)

Note that casts of some of the vertebrae from the specimen are currently curated in the Texas Memorial Museum (Austin, TX) as TMM-41379). 

ANOTHER LARGE CROCODILE FROM THE DAKOTA FORMATION:

LEFT: This is a dorsal view of the posterior portion of the the skull of a large crocodile tentatively identified as Terminonaris sp. (FHSM VP-2079) from the Dakota Formation of Russell County, Kansas. It was discovered in 1959 by Timmy Harbaugh of Russell, and collected by Myrl Walker.

RIGHT: Two of the limb bones of FHSM VP-2079. Other remains include vertebrae and possible elements of the pectoral or pelvic girdles. 

CROCODILE REMAINS FROM THE KIOWA SHALE:

LEFT: FHSM VP-2989 - A portion of the lower jaw (dentary) and two patches of dermal scutes from a crocodile in the Kiowa Formation of Clark County, Kansas. The specimen was collected by Myrl Walker.

RIGHT: The proximal end of an unusual bone  (KUVP 1199) collected by S.W. Williston (1894) from the Kiowa Formation (Clark County): 
Williston's (1894, 1898) description: 揟he upper end of a femur found in the same region, and from near the Red Beds, appears to belong to the same kind  of an animal as does the vertebra described above. The shape is not unlike that of a human femur, with the trochanters evidently small and placed much below the level of the head. The neck is stout, the head gently convex, with an angular border. The shaft below the trochanters is somewhat flattened from be fore back, but becomes more transverse below. The shaft is hollow, with firm walls, not more than one third of an inch in thickness. The portion preserved measures 210 mm.?/span>

Williston (1903) later described KUVP 1199 as the femur of a new species of giant pterosaur ("Apatomerus mirus"). It is most likely the upper end of a plesiosaur propodial. 

MORE RECENT DISCOVERIES:

More recently, Joe Beamon, a Fort Hays graduate student, reported (1999) crocodile teeth and scutes from a quarry in the Early Cretaceous Kiowa Formation (McPherson County) in his 1999 Masters thesis.Since then, I have collected crocodile teeth from the same shale quarry and teeth, scutes and bone fragments(?) from the Dakota Formationnear Wilson Lake in Russell County. (See also Everhart, 2004, 2011)

LEFT:  A broken crown of a crocodile tooth (FHSM VP-13544) collected by Joseph Beamon from the Kiowa Formation in McPherson County. 

RIGHT:  Two crowns of  crocodile teeth (FHSM VP-13547) collected by Joseph Beamon from the Kiowa Formation in McPherson County. 

LEFT:  Four crowns of  crocodile teeth (FHSM VP-13548) collected by Joseph Beamon from the Kiowa Formation in McPherson County. 

RIGHT:  Two crowns of  crocodile teeth (FHSM VP-13559) collected by Joseph Beamon from the Kiowa Formation in McPherson County. 

LEFT: A small crocodile scute (FHSM VP-15723) collected by Keith Ewell in 2004 from the Dakota Formation in Russell County.

RIGHT:  Fragments of crocodile scutes (FHSM VP-13554) collected by Joseph Beamon and others in 1998 from the Kiowa Formation in McPherson County, Kansas. A large number of small fragments of crocodile teeth were also collected.

LEFT:  An well-polished crocodile scute collected by Keith Ewell in 2004 from the Dakota Formation in Russell County. Many of the bones, scutes and teeth found in this part of the Dakota Formation were worn smooth by abrasion from the river or beach sand.  

RIGHT:  Two crowns of  crocodile teeth (FHSM VP-15724) collected by Keith Ewell in 2004 from the Dakota Formation in Russell County. 

LEFT:  Four views of a small crocodile tooth collected from the Dakota Formation, Russell County, Kansas collected by Keith Ewell in 2005.  More here.

RIGHT: A crocodile tooth (FHSM VP-2250) collected from the Dakota Formation in 1967, still embedded embedded in the iron-stained, sandy matrix. 

LEFT: Partial rostrum of Terminonaris cf. T. browni Osborn, 1904 (FHSM VP-4387) in dorsal and ventral views from the Fairport Chalk Member (Middle Turonian), Carlile Shale, Russell County, Kansas.

RIGHT: Possible crocodile bone fragments collected by Keith Ewell in 2004. from the Dakota Formation, Russell County, Kansas. 

In 2007, Kenshu Shimada and David Parris reported on the snout (above) of a long-snouted crocodyliform (Terminonaris) from the Fairport Chalk (Carlile Formation) of Russell County. This is an unusual specimen because the snout came from a shore-dwelling crocodile, but it was found in marine sediments (chalk) deposited far off-shore. It is also the only known crocodile from the the Carlile Formation.  The most likely explanation was that the bloated carcass floated out to sea where it fell apart and was buried. This genus was originally named Teleorhinusbut that name was pre-occupied (See Wu,, et al., 2001). 


Literature Cited: 

Beamon, J.C. 1999. Depositional environment and fossil biota of a thin clastic unit of the Kiowa Formation, Lower Cretaceous (Albian), McPherson County, Kansas. Unpublished MS Thesis, Fort Hays State University, Hays, KS, 97 pp. 

Cope, E.D. 1872. On the geology and paleontology of the Cretaceous strata of Kansas. Annual Report of the U.S. Geological Survey of the Territories 5:318-349.  

Cope, E.D. 1875. The Vertebrata of the Cretaceous formations of the West. Report, U. S. Geological Survey Territories(Hayden) 2, 302 pp., 57 pls. 

Everhart, M.J. 2004. First record of the hybodont shark genus, ?i>Polyacrodus? sp., (Chondrichthyes; Polyacrodontidae) from the Kiowa Formation (Lower Cretaceous) of McPherson County, Kansas. Kansas Academy of Science, Transactions 107(1/2):39-43. 

Everhart, M.J. 2011. Occurrence of the hybodont shark genus Meristodonoides (Chondrichthyes; Hybodontiformes) in the Cretaceous of Kansas. KansasAcademy of Science, Transactions 114(1-2):33-46.

Everhart, M.J. 2016. William E. Webb ?Civil War correspondent, railroad land baron, town founder, Kansas legislator, adventurer, fossil collector, author. Kansas Academy of Science, Transactions 119(2):179-192. (Hyposaurus vebbi). 

Garcia, W.J. 1999. Teleorhinus (Crocodylimorpha) from the Dakota Formation (Cretaceous) of Kansas, with a discussion of its paleoecology. Unpublished Masters Thesis, Fort Hays State University, Hays, Kansas, 97 pp.

Lane, H.H. 1946. A survey of the fossil vertebrates of Kansas, Part III, The Reptiles, Kansas Academy Science, Transactions 49(3):289-332, 7 figs. 

Lee, Y.-N. 1997. The Archosauria from the Woodbine Formation (Cenomanian) in Texas. Journal of Paleontology 71(6):1147-1156.

Liggett, G.A. 1997. The Beckerdite local biota (Early Hemphillian) and the first Tertiary occurrence of a crocodilian from Kansas. Kansas Academy of Science, Transactions 100(3-4):101-108.

Mehl, M.G. 1934. Crocodilian remains Dakota sandstone of western Kansas. Proceedings of the Geological Society of America. (Meeting abstract, 1933, p. 368).

Mehl, M.G. 1941. Dakotasuchus kingi, a crocodile from the Dakota of Kansas. Denison University Bulletin, Journal of the Scientific Laboratories 35:47-65.  

Schwimmer, D.R. 2002. King of the Crocodylians - The Paleobiology of Deinosuchus. Indiana University Press, 220 pages. 

Shimada, K. and Parris. D.C. 2007. A long-snouted Late Cretaceous crocodyliform, Terminonariscf. T. browni, from the Carlile Shale (Turonian) of Kansas. Kansas Academy of Science, Transactions 110(1/2): 107-115. 

Vaughn, P.P. 1956. A second specimen of the Cretaceous crocodile Dakotasuchusfrom Kansas. Kansas Academy of Science,  Transactions 59(3):379-381.  

Williston, S.W. 1898. Crocodiles. The University Geological Survey of Kansas, Part IV, 4:75-78, pl. 9.

Williston, S.W. 1894. On various vertebrate remains from the lowermost Cretaceous of Kansas. Kansas University Quarterly 3(1):1-4, pl. I.

Williston, S.W. 1903. On the osteology of Nyctosaurus (Nyctodactylus), with notes on American pterosaurs. Field Museum Publications (Geological Series ) 2(3):125-163, 2 figs., pls. XL-XLIV. (includes description of Apatomerus mirus, KUVP 1199)

Wu, X.-C., Russell, A.P. and Cumbaa, S.L. 2001. Terminonaris(Archosauria: Crocodyliformes): new material from Saskatchewan, Canada, and comments on its phylogenetic relationships. Journal of Vertebrate Paleontology 21:492-514.


  

  

 

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