Giant cephalopods from the Upper Cretaceous of the ...

Beneath Wyoming’s waves: marine paleontology, Cavagelli, J.P. (ed.), Tate Geological Museum 16th Annual Tate Conference, Casper, Wyoming, June, 2010: 66-78.

Enchoteuthididae: Giant cephalopods from the Upper Cretaceous of the Western Interior Neal L. Larson Black Hills Institute of Geological Research & Black Hills Museum of Natural History PO Box 643, 117 Main Street, Hill City, South Dakota 57745 email: [email protected]; fax: 605-574-2518 Abstract: Giant squids and octopi have captivated the imagination of researchers and the public for more than a century. From books to scientific articles to new discoveries on the web, our knowledge of these recent giants is growing but what we know of giant fossil coleoids is limited to only a few scientific papers. The Krakens of the Cretaceous, like their modern counterparts, were formidable giants. Recent discoveries of these giants have provided new information to the size and distribution of these incredible creatures.

Introduction: Giant squids and octopus were a thing of mystery and fear to early sailors. For centuries, men at sea reported seeing monstrous cephalopods that could swallow ships whole. Anyone who set sail on the ocean was in fear that a giant squid or octopus was waiting to pull their ship under the waves and devour the crew. Jules Verne’s 1869 classic novel “20,000 leagues under the Sea” pitted Captain Nemo and his crew of the Nautilus in a life and death battle against a giant cephalopod. Some of these giant squids were enormous, and according to Jacques Cousteau (1973) a specimen of Architeuthis found in 1878 near Newfoundland had a sixmeter long body (mantle approximately three meters long) and nine-meter long tentacles for a total length of 15 meters (five times the length of the mantle)! Throughout much of this last two decades Architeuthis has captivated the imagination of researchers and the public. Books and documentaries have presented quite a bit of information regarding these giants. As recently seen on PBS and NOVA television programs, scientists and cameramen have set out on expeditions in search of the giant squid to view them in their own environment. However, it is usually the fishermen who catch them and as a result some of these specimens have found their way into photographs and public institutions. We have a growing knowledge of these living giants but what we know about monster fossil squids are limited to only a few reports (Nicholls and Isaak, 1987; Martin, 1990; Everhart, 2005, Larson, 2010). The Krakens of the Cretaceous

(Fig. 1), like their modern counterparts, were formidable giants reaching sizes comparable with Architeuthis. Recent discoveries of Enchoteuthididae Larson (2010) have shown that members of this family also achieved this monster-size status. In 1898, Logan described Tusoteuthis longa, the first ‘large’ squid discovered in the Western Interior. The remains of that specimen consisted of only a poorly preserved, incomplete, spoonshaped gladius. This was not a large squid; its gladius measured only 40 cm by 16 cm wide with an incomplete rachis only 1.5 cm in diameter. Based on the proportions of a nearly complete gladius, MDM Q84.03.18 (Nicholls and Isaak, 1987), the entire gladius length of Logan’s type would have measured about 120 cm. If the arms and body of these ancient squids were proportioned similar to Architeuthis, where the combined arm and mantle length are more than twice the length of the gladius, and if they had tentacles, this living animal would have measured approximately 6 meters in length! Green (1974) described several new genera and species of teuthids that lived during the deposition of the Niobrara Formation and also illustrated these different Coniacian, Santonian and Campanian teuthids. Most researchers since Green synonymized all species and genera under Tusoteuthis longa (Stewart, 1977; Nicholls and Isaak, 1987), this was based on the belief that the differences in gladius shape were simply variations in sex, age and size without comparing those characters to similar differences between genera and species of extant squids.

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Fig. 1. A fight between Enchoteuthis and Elasmosaurus (illustration courtesy of Tracy Ford. Geological Setting: Enchoteuthididae Larson (2010) has been discovered in the Late Cretaceous marine sediments of the Western Interior from the Campanian Pierre Shale of Colorado, Kansas, North Dakota, South Dakota, Wyoming, and Manitoba and from the Coniacian through the lower Campanian Niobrara Formation (also known as the Niobrara Chalk or Smoky Hill Chalk) in Colorado and Kansas and probably existed also in the Niobrara Formation in Wyoming and South Dakota (Table 1), though none have yet been reported or recognized. Several authors have published on the biostratigraphic zones of the Niobrara Formation and Pierre Shale, most notably Gill & Cobban (1966), Gill et al. (1972), Hattin (1982), Stewart (1990), Carpenter (1996 & 2003), Larson, et al. (1997) and Cobban et al. (2006). While the invertebrate biostratigraphy of the Pierre Shale is well documented (see previous citations) the invertebrate biostratigraphy of the Niobrara Formation is difficult to correlate and zone comparisons are almost impossible to

make. Within the Niobrara Formation, diagenesis has destroyed the aragonitic shell of ammonites and other mollusks, leaving only the calcitic species. Within the Pierre Shale aragonite is easily preserved while calcite is often dissolved during the formation of concretions. Because ammonites had aragonitic shell, we have a good record of ammonites from the Pierre Shale (Larson, et al. 1997; Cobban 2006), however there is only a poor to incomplete record from the Smoky Hill Chalk (Miller, 1968). These obvious differences often make correlation of the two formations very difficult since fauna is often differentially preserved within each formation because of the chemistry of the deposition of the rocks. The genera within the family Enchoteuthididae as reported by Larson (2010) include: Tusoteuthis Logan, 1898; Niobrarateuthis Miller, 1957; Enchoteuthis Miller & Walker, 1968; and Kansasteuthis Miller & Walker, 1968. All of these genera have been reported as occuring from the Smoky Hill Chalk (or Niobrara Formation) of western Kansas and only

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Tusoteuthis and Enchoteuthis have been reported from the Pierre Shale of Wyoming (Larson, 2010). The type of Tusoteuthis was collected from the Hesperornis beds of the Niobrara Formation; the type of Enchoteuthis was collected just above the Uintacrinus socialis Zone of the Niobrara Formation. Carpenter (2003) placed these beds in the lower Campanian. Both Niobrarateuthis and Kansasteuthis were collected from lower zones in the Niobrara Formation and they are known only as a few isolated specimens from the lower Santonian and upper Coniacian. This paper addresses the relationships between the different genera of Enchoteuthididae from the Western Interior and describes the characters that make them unique. Previous studies: Logan (1898) described Tusoteuthis longa from the Niobrara Chalk (or Niobrara Formation) of western Kansas. This was only the third teuthoid gladii discovered within the Western Interior, the first being Belemnitella bulbosa (Meek and Hayden, 1856) and the second, Actinosepia canadensis (Whiteaves, 1897). Meek and Hayden (1860) also described what they believed to be another cephalopod gladii: Phylloteuthis subovatus from the Fox Hills Formation but this was determined to be nothing more than a plant (Green 1977 and Larson 2010). Miller (1957) described Niobrarateuthis bonneri from the Niobrara Formation based on a nearly complete gladius that was much larger and much more complete than Tusoteuthis. Miller & Walker (1968) described Enchoteuthis melanae and Kansasteuthis lindneri from the Niobrara Formation of Kansas. Miller (1968) compiled a landmark publication on the environment and the known invertebrate fauna of the Niobrara Formation. Green (1977) described another new species, Niobrarateuthis walkeri from Niobrara Formation of western Kansas, based on a very different and nearly complete gladius. Green (1977) published, described and illustrated the differences of all known ‘teuthids’ from the Niobrara Formation. In a short abstract, Stewart (1977) noted that some of the previous researchers had confused the dorsal and ventral views of the gladii in the Niobrara teuthids; he also was the first to report

these teuthids had been found in the overlying Pierre Shale and the underlying Carlile Formation. Nicholls & Isaak (1987) published a major paper on giant Tusoteuthis longa occurring in the Pembina Member of the Pierre Shale (lower, middle Campanian) of southern Manitoba. Larson (2010) illustrated and redescribed nearly all known Tusoteuthis and Enchoteuthis specimens from the Niobrara Formation and Pierre Shale and erected the Family Enchoteuthididae for these unique cephalopod forms. Repositories: BHI Black Hills Institute of Geological Research Collection, Black Hills Museum of Natural History, Hill City, South Dakota FHSM

Fort Hays State University, Sternberg Museum of Natural History, Hays, Kansas

KU

University of Kansas, Natural History Museum, Lawrence, Kansas

MDM

Canadian Fossil Discovery Centre (previously named the Morden and District Museum), Morden, Manitoba

MMMN

Manitoba Museum of Man and Nature, The Manitoba Museum, Winnipeg, Manitoba

UCM

University of Colorado Museum, Boulder, Colorado

Review of known taxa: Subclass Coleoidea Bather, 1888 Order Teuthida Naef, 1916 Family Enchoteuthididae Larson, 2010 Larson (2010) described the family Enchoteuthididae based upon the unique shape of the gladius in conjunction with its proportional length, conus shape and the complexity of its free rachis. All that has been found of enchoteuthoids to date is the pen, or gladius. To date no one has recognized or discovered their jaws or radula, nor do we know how many arms they had, how long they were and whether or not they had tentacles.

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Figure 2. A basic diagram of the enchoteuthoid gladius. In Enchoteuthididae, the gladius shape (Fig. 2) is characteristically spoon, spatula, shovel (spade) or spear shaped. It consists of a long, cylindrical, free rachis extending into and terminating anywhere from one/fifth, to one/half, to two/thirds, to all of the way into the blade at the end of its two large vanes (lateral fields) depending on which genera it is. The rachis always forms a dorsal ridge above the vanes that are dorsally concave. The conus and anterior vanes are dorsally convex at the termination of the rachis in the middle portion of the blade. The blade, (a combination of the vanes, non-free rachis and conus) is generally two to three times longer than it is wide and the free rachis length is generally two to two and one-half times the

blade length. As in all squids, the rachis points forward, the conus lies at the end of the rachis and lateral fields are in the rear of the mantle (Fig. 3). The vanes most-likely helped anchor their fins. The teuthoid gladius is a fascinating structure composed of many different parts whose same characteristics are used by modern coleoid researchers for the separation of genus and families. According to Toll (1998), some of these different characters include the size, complexity, length, and position of the rachis; the number and position of the vanes; the relative width and length of the vanes and the rachis; and the presence and type of conus.

Figure 3. An illustration showing where the gladius lies within the mantle of the squid. Even though there are relatively few complete enchoteuthoids from the Western Interior, their

conus is quite different than modern coleoids. The conus in these ancient forms lies near the

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junction of the rachis in the blade, surrounded by the lateral and anterior vanes; whereas in modern teuthids the conus makes up the posterior of the gladius and is often cone shaped (thus the name). Even with this major difference, the complex rachis and the broad vanes of enchoteuthoids much more resemble the gladius of many modern squids than any other extinct forms. The genera included in this family are: Tusoteuthis Logan, 1898; Niobrarateuthis Miller, 1957; Enchoteuthis Miller & Walker, 1968; and Kansasteuthis Miller & Walker, 1968. Genus Enchoteuthis Miller & Walker, 1968 Type Species: Holotype is FHSM 13049 Enchoteuthis melanae Miller & Walker 1968 (p. 176, 179-180), reposited within the collection of the Fort Hays State University, Sternberg Museum of Natural History, Hays, Kansas. The type (Fig. 4) is incomplete, missing its entire free rachis, measures 10.5 cm wide by 21.5 cm long. It was collected from the Niobrara Formation, Smoky Hill Member, near Russell Springs, Logan County, Kansas.

Description: The gladius of Enchoteuthis melanae is characterized by a shovel or spade shape. The rachis is attached to-and extends into broad vanes and the median field and conus. The type of Enchoteuthis is lacking its free rachis but other more complete specimens confirm that the rachis is long. Gladius composed of corneous and chitinous material consisting of a long, freerachis extending from one-half to two-thirds of the way into the broad blade. The rachis is often complex and can be made up of many rod-like and wavy structures in a complex cross-section. The blade is two times longer than wide and consists of two parts: paired anterior vanes that are dorsally concave with the lateral fields and separated by the rachis. The vanes terminate one-half to two-thirds of the way into the blade. The posterior of blade is made up of a large conus that is seemingly a continuation to and adjacent to the vanes. The dorsal view of the conus is moderately convex and rounded to bluntly acute. The blade is widest near the anterior portion.

Figure 4. Holotype of Enchoteuthis melanae FHSM 13049, dorsal view (Mike Everhart photo). Additional specimens: Enchoteuthis melanae BHI 5873 (Fig. 5) is a large specimen from the

Niobrara Chalk of Gove County, Kansas. Its blade measures 48 cm long by 31 cm wide and

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is very spade shaped. The rachis is very incomplete and missing most of its free rachis due to weathering. The rachis is complex in cross section and measures 3.5 cm wide. The entire gladius would have been approximately 150 cm in length, or more, if complete. While most squid from the Santonian-lower

Campanian Niobrara Formation are considered large, (Everhart, 2005) the largest gladius is only about 1.5 meters. It is interesting to note, however, that later specimens from the lower middle Campanian Pierre Shale grew much larger.

Figure 4. Enchoteuthis melanae BHI 5873, dorsal view. Nicholls and Isaak (1987) reported on six specimens of Enchoteuthis, referred to as Tusoteuthis longa, from the Pembina Member of the Pierre Shale (lower middle Campanian) in Manitoba. They collected three very notable specimens. MDM Q84.03.18 has a nearly complete rachis, almost three times longer than its blade. Since this is the only large specimen of Enchoteuthis with a complete (undamaged) rachis, proportions from this specimen were used to calculate the sizes of the other specimens with incomplete rachii. MDM Q77.02.77 has a complete blade that measures 64.6 cm x 32.5 cm. based on the previous specimen, its entire gladius length would have measured about 180 cm. Their largest specimen, MMMN I 794, has an incomplete blade measuring 68 cm long by 35 cm wide with a partial rachis 5 cm wide. Its

rachis width is nearly 40% wider than the largest recorded from the Niobrara Formation. Based on previous estimates its entire gladius would have been 210 - 250 cm in length! If this specimen were proportioned like Architeuthis (total length about four times the gladius length) it would have had been approximately 12 meters long or larger! KU 314494 (Fig. 6A) is a large, nearly complete Enchoteuthis melanae, collected from the Baculites obtusus Range zone of the Pierre Shale in eastern Wyoming by the University of Kansas. Its blade (Fig. 6B) measure 66 cm long by 38 cm wide. The nearly complete rachis is 107 cm long, its free rachis measures 73 cm long by 5 cm wide and the entire length of its gladius is 141 cm in length. The rachis terminates

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anteriorly with an apparent pathology (see Fig.

6C), perhaps the result of a healed bite.

Figure 6A. Enchoteuthis melanae KU 314494 with Placenticeras sp., dorsal view (Corinne Meyers photo).

Figure 6B. Enchoteuthis melanae KU 314494, close up of the ‘blade’ (Corinne Meyers photo).

Figure 6C. Enchoteuthis melanae KU 314494, close up of the rachis (Corinne Meyers photo). Neil Landman of the American Museum of Natural History collected a giant Enchoteuthis from the Baculites obtusus zone of the Pierre Shale in eastern Wyoming. That specimen was larger than KU 314494, measuring well over 150 cm in length with an incomplete rachis. It is

estimated to have been at least 210 cm in length if complete. During that same collecting expedition, Black Hills Institute of Geological Research collected a portion of a giant Enchoteuthis (Fig. 7A). BHI 5812 is larger than any other known specimen to

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date. The specimen is missing most of its gladius due to weathering and preservation (Fig. 7B). The partial blade measures 46cm long by 27cm wide. It was found in a concretion, that when broken open, split between the two halves. The width of BHI 5812’s uncrushed rachis is 7.2 cm across (Fig 7C & 7D), or 40% larger than any other known enchoteuthoid. As seen in its

cross section (Fig 7C), there is no crushing. The absence of crushing in the rachis is common in enchoteuthoids found within the Baculites obtusus zone of the Pierre Shale. The complexity of the rachis (as seen in Fig. 7C) is similar to what is observed in Architeuthis and quite different than any other extant form.

Figure 7A. Enchoteuthis melanae BHI 5812, split view; scale = 10 cm.

Figure 7B. Enchoteuthis melanae BHI 5812 illustrating missing blade portions, scale = 10 cm.

Figure 7C & 7D. Rachis of Enchoteuthis melanae BHI 5812, scale in cm.

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If BHI 5812 had been complete, by comparison with other specimens, the blade of BHI 5812 would have measured nearly a meter long by 0.6 meter wide and its entire gladius would have been 3 meters or more in length. Using previous estimates, BHI 5812 then would have had a body length more than 6 meters and if it had tentacles proportioned as in living squids, it would have been more than 15 meters in length, or about the same size as the Newfoundland Architeuthis reported by Jacques Cousteau (1878). This monster squid would have rivaled many of the large vertebrate giants (such as mosasaurs, plesiosaurs and Xiphactinus) as top predator.

Remarks: Enchoteuthis attains a large size unseen in any other teuthid. Several other specimens of the species have been reported (see Larson, 2010). Because the complexity of the rachis of Enchoteuthis is so similar to some of the extant forms, it may help us speculate if Enchoteuthididae had any descendants. Enchoteuthis has been found from the lower Campanian to lowermost middle Campanian of the Western Interior (see Table 1) and has been reported from western Kansas, eastern Wyoming, western South Dakota, eastern North Dakota and southern Manitoba.

Fig. 8. Holotype of Tusoteuthis longus, KU 113463, dorsal view; see description for size. Genus Tusoteuthis Logan, 1898 Species included: Tusoteuthis longus Tusoteuthis cobbani.

and

Type Species: Holotype is KU 113463 Tusoteuthis longus Logan, 1898 (p. 497-498, Pl. 110, Fig. 1). The type is very incomplete (see Fig. 8), missing most of its blade and nearly all of its rachis. The specimen has enough of its lateral vanes, conus and the anterior portion of the blade preserved to give its shape. The blade is 35.5 cm long and 13.5 cm wide (based on evidence present on the type) or approximately

twice as long as it is wide. It is unknown how far into the blade the rachis extended. Description: Gladius characterized by spearlike shape. Rachis is long, attached to-and extending into vanes with large, primary conus and extends about one-half of the way into the blade. The rachis is cylindrical with small rods and cones may become more complex in larger specimens. The blade is two to three times longer than wide and consists of two parts: paired anterior vanes that are dorsally concave with the lateral fields (vanes) separated by the rachis and the conus. The vanes terminate one-

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half way into the blade at the conus. The posterior of blade is made up of large anterior vanes that are moderately convex and acutely blunted. The lateral fields are widest in the central portion of the blade; the rachis points anteriorly, the anterior vanes point posteriorly. Gladius composed of corneous and chitinous material. Tusoteuthis occurs from the upper

Santonian to upper Campanian in age (see Table 1) and is known only from Kansas. Additional specimens: Tusoteuthis BHI 7010 (Fig. 9) is a nearly complete specimen from the lower Campanian of the Niobrara Chalk. The blade measures 23.3 cm long by 10 cm wide. The rachis is incomplete and measures 36.5 cm long by 1.5 cm in width. The entire gladius length measures 49 cm in length.

Fig. 9. Tusoteuthis longus, BHI 7010, split-dorsal view of nearly complete gladius in matrix; scale = 10 cm. Remarks: The holotype of Tusoteuthis longus (Fig. 8) is fragmentary at best. As a result of its incompleteness, several genera and species of coleoids from the Niobrara Chalk have been designated. The types of Niobrarateuthis, Enchoteuthis, Kansasteuthis and Niobrarateuthis were all described as differing from Tusoteuthis in regards to the shape of their blade (spoon, spear or shovel), how far the rachis extends into the lateral fields, and even from the shape and cross-section of the rachis; even though the type of Tusoteuthis lacks nearly all of these defining attributes. Tusoteuthis cobbani: Type species (Fig. 10) was described by Larson, 2010 (p. 31-32 fig. 1718) and is from the Baculites cuneatus zone of the upper Campanian (see Table 1), Pierre Shale, Pennington County, South Dakota. Both the

holotype and paratype are reposited in the Black Hills Museum of Natural History, Hill City. Description: The gladius of Tusoteuthis cobbani is characterized by a long, free-rachis and spear to spoon shaped blade. Gladius is composed of corneous to chitinous-like material. The blade is narrow, two and one-half times as long as it is wide, with dorsally concave lateral fields (vanes), and dorsally convex conus and is widest at the central portion of the vanes. The rachis extends into the blade, and terminates near the middle of the blade at the conus. On the dorsal side, the rachis forms a tall, thin ridge above the depressed lateral fields before it terminates near mid-blade. The rachis consists as a single shaft. The species was included under Tusoteuthis based on overall shape of the blade and complexity of the rachis.

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Fig. 10: Tusoteuthis cobbani, holotype, BHI 4138, dorsal view; scale = 5 cm Genus Niobrarateuthis Miller, 1957 Species included: Niobrarateuthis bonneri and Niobrarateuthis walkeri. Type Species: Holotype FHSM 7959 Niobrarateuthis bonneri Miller, 1957 (p. 809814, Fig. 1 & 2) reposited within the collection of the Fort Hays State University, Sternberg Museum of Natural History, Hays, Kansas. There is only one specimen attributed to the species. Description: The type of Niobrarateuthis bonneri (Fig. 11) has an unusual spatula-like shape. Rachis is broad, long, attached to-and extending into lateral vanes. Gladius composed of corneous and chitinous material with a long, free-rachis extending four-fifths of the way into the blade. According to Miller (1957), the rachis

does not seem to be complex but rather single rods (very different than Enchoteuthis). The blade is as long as wide and consists of two parts: paired anterior vanes that are dorsally concave with the lateral fields separated by the rachis. As in other enchoteuthoids, the conus lay at the termination of its rachis. The anterior of blade is made up of large vanes that are moderately convex and rounded. It is unknown if the posterior of the gladius is complete or incomplete, it does not appear to be folded. The vanes are wide throughout the central portion of the blade and as in all enchoteuthoids, the rachis points anteriorly. The gladius is 50 cm in length. The blade is 19 cm long by 13.3 cm wide. The free rachis is 31 cm long, the entire rachis is 47 cm long terminating at the conus; and maximum diameter of the rachis is 2.2 cm.

Fig. 11: Niobrarateuthis bonneri FHSM 7959, dorsal view; scale in cm (Mike Everhart photo).

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Niobrarateuthis walkeri: Type species of FHSM 13901 Niobrarateuthis walkeri Green, 1977 (p. 993-995, Fig. 1 & 2) consists of a single specimen with a well-inflated, nearly complete gladius from the Smoky Hill Chalk of Logan County Kansas and is reposited within the collection of Sternberg Museum of Natural History in Hays, Kansas. Description: The gladius is paddle-like in shape with a blade 23.5 cm long, by 8.8 cm wide and a total length of 58.3 cm. Rachis is 44.8 cm long with the anterior end broken off and 2.2 cm wide at maximum diameter. The rachis extends into the blade about two-fifths the length, much different than N. bonneri which extends into the blade nearly four-fifths the length. Its conus is very convex, begins at the termination of the rachis and makes up most of the posterior of the gladius. Maximum diameter is beyond midway of the blade. The posterior of the gladius terminates with a somewhat blunted apex. Remarks: Both types of Niobrarateuthis are quite different from each other and this author feels they should not be included within the same genus. Niobrarateuthis walkeri seems to resemble Enchoteuthis melanae more than Niobrarateuthis bonneri. Evaluations are based on shape of the blade (vanes and conus), proportions of blade width versus length, conus size and shape, anterior vane shape, distance of the rachis into the vanes and complexity of the

rachis. Both are dorsal views of the gladius. Both specimens are Santonian age, Niobrara Formation of western Kansas (see Table 1). Genus Kansasteuthis Miller & Walker 1968 Type Species: Holotype FHSM 13062 Kansasteuthis lindneri Miller & Walker, 1968 (p. 179-180, Pl. 3, Fig. 2), reposited within the collection of the Fort Hays State University, Sternberg Museum of Natural History, Hays, Kansas. Description: The type of Kansasteuthis lindneri (Fig. 12) was described based upon a very unusual ‘split’ rachis and is an anomaly consisting of a single specimen. Description is simple: a ‘split’ or ‘double’ rachis that extends only slightly into very incomplete, tapered vanes. Because the specimen is so incomplete it is difficult to determine how unique it truly is. However, its rachis does not extend very far into the vanes and this is quite different than any other species. Its age is upper Coniacian (see Table 1). There are no other specimens, other than the type, assigned to the genus. This author believes its status as a distinct genus and species to be doubtful. The specimen is from the Niobrara Formation, Smoky Hill Member, Rooks County Kansas.

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Fig. 12: Kansasteuthis lindneri FHSM 13062, ventral view? scale in cm (Mike Everhart photo). Predation and Pathologies: Some enchoteuthoid cephalopods show signs of predation and pathologies. Carpenter (2006, p. 139, Fig. A) illustrated a partial enchoteuthoid gladius inside the stomach region of a Cimolichthys (UCM 29667 & 29556). In the

same paper, Carpenter (2006, p. 139, Fig. B & C) also illustrated a nearly complete gladius of an Enchoteuthis melanae from the Sharon Springs Member, Pierre Shale (UCM 29668) with tooth punctures on the rachis that he attributed possibly from a Tylosaurus.

Fig. 12. A bitten rachis from the Niobrara Chalk; note the regular spacing of the tooth marks on the rachis (specimen courtesy of Glenn Rockers). Another specimen collected from the Smoky Hill Member of the Niobrara Chalk was noted in the collections of Glenn Rockers (Paleosearch) Hays, Kansas. This specimen (Fig. 12) is quite interesting in that it shows extreme predation with the blade completely gone yet a nearly complete rachis. There are four deep gouges on the rachis most likely attributed to the bite from a large mosasaur. Comments: Several other specimens of Enchoteuthididae are known to exist with more than one dozen other specimens located within the collections at the University of Kansas alone. Some of these were reported in Larson (2010) but there are other specimens that were not measured or photographed. Two specimens of Enchoteuthis from the Pierre Shale in eastern Wyoming (probably from the lower, middle Campanian) are located in the collections of the Colorado School of Mines Geology Museum at Golden (Carpenter, 2006). The one specimen within the collections of AMNH is also from the lower, middle Campanian, Pierre Shale of eastern Wyoming (Neil Landman, personal communication 2008). Another Enchoteuthis specimen from the Pembina Member of the Pierre Shale in northeast North Dakota is

reposited at North Dakota Heritage Center in Bismarck, ND (Hoganson, 2006). There are several specimens from the Pembina Member of the Pierre Shale (lower middle Campanian) in Manitoba as reported by Nicholls and Isaak (1987) located at the Canadian Fossil Discovery Centre in Morden, Manitoba and in the Manitoba Museum of Man and Nature in Winnipeg, Manitoba. Finally there are a couple of specimens from the Smoky Hill Member of the Niobrara Chalk in the collection of the Rocky Mountain Dinosaur Resource Center, Woodland Park, CO. Further study on these specimens will undoubtedly add to our knowledge of these wonderful creatures. Conclusions: Enchoteuthis was a giant invertebrate possibly the size as the largest reported Architeuthis. Because of its size and weapons (arms and jaws), Enchoteuthis would have rivaled most of the large Cretaceous vertebrates (mosasaurs, plesiosaurs and fish) for dominance in the Western Interior Seaway. As in extant squids enchoteuthoids were predators with a diet most likely like that of extant squids. Just as larger vertebrates and cephalopods prey upon living squids, so mosasaurs, plesiosaurs, turtles, fish

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and other large cephalopods probably predated on enchoteuthoids; though because of its size it could have defended itself quite well. Because the rachis complexity in enchoteuthoids is so similar to some extant forms, further studies on the rachis may determine if Enchoteuthididae is related to any extant forms. Recognition and further collecting of Enchoteuthididae will result in more specimens and thus a better understanding of the family, genera and species. This may in turn help us to determine if there are any direct relationships between them and any extant coleoids. Acknowledgements: This paper could not have been completed without the cooperation and assistance of the following: Corinne Meyers, Larry Martin, David Burnham, Talia Karim and Amanda Falk from the University of Kansas at Lawrence who assisted the author with specimens, photographs and copies of hard-to-find publications; Mike Everhart of Oceans of Kansas Paleontology at Hays, KS provided photos of the Sternberg Museum specimens; Tracy Ford, San Diego, CA References: Bather F. A. 1888. -Shell-growth in Cephalopoda (Siphonopoda). Annals and Magazine of Natural History 6: 421-427. Carpenter K. 1996. Sharon Springs Member, Pierre Shale (lower Campanian): depositional environment and origin of its vertebrate fauna, with a review of North American Cretaceous Plesiosaurs. Ph.D. Thesis, University of Colorado, Boulder. Carpenter K. 2003. Vertebrate biostratigraphy of the Smoky Hill Chalk (Niobrara Formation) and the Sharon Springs Member (Pierre Shale): 421437, in Harries P.J. (ed.), Approaches in HighResolution Stratigraphic Paleontology. Kluwer Academic Publishers, Netherlands. Carpenter K. 2006. Comparative vertebrate taphonomy of the Pembina and Sharon Springs Members (Middle Campanian) of the Pierre Shale, Western Interior. Rochester Institute of Vertebrate Paleontology, Paludicola 5(4): 125149. Cobban W.A., Walaszczyk I., Obradovich J.D. & McKinney K.C. 2006. A USGS Zonal table

allowed me to use a photo of his drawing; Marion C. Bonner (deceased) and Dave Tanking currently in Assaria, KS collected most of our Kansas specimens; Luke Larson assisted in preparation and preparation on coleoid pens; Pete Larson and James Honert assisted in collecting; Tim Larson assisted me with some of the plates; Glenn Rockers of Hays, KS allowed me access to his pathological rachis; Dirk Fuchs of Berlin, Germany, Steve Jorgensen of Highlands Ranch, CO, Neil Landman of New York, NY and J. P. Cavigelli of Casper, WY kindly reviewed and helped edit the manuscript. Thanks to the landowners around the Black Hills and in western Kansas who allowed the collection of these fossils. A very special thank you to Dr. Dirk Fuchs of Berlin, Germany whose help on this project was immense; he attempted to help me understand the morphology of the enchoteuthoid gladius, the terminology involved, provided peer review and gave me much needed advice.

for the Upper Cretaceous middle CenomanianMaastrichtian of the Western Interior of the United States based on ammonites, Inoceramids, and radiometric ages. U.S. Geological Survey, Open-File Report 2006-1250: 46 p. Cousteau, J. 1973. Octopus and Squid, the soft intelligence. Doubleday & Company, New York, 304 p. Everhart M. J. 2005. Oceans of Kansas, Indiana Press, Bloomington, 322 p. Gill J.R. & Cobban W.A. 1966. The Red Bird section of the Upper Cretaceous Pierre Shale in Wyoming. U.S. Geological Survey Professional Paper 393-A, 73 p., Gill J.R., Cobban W.A., & Schultz L.G., 1972. Stratigraphy and composition of the Sharon Springs Member of the Pierre Shale in western Kansas. U.S. Geological Survey Professional Paper 728, 50 p. Green R. 1974. Teuthids of the Late Cretaceous Niobrara Formation in Kansas and some ecological implications. The Compass, Sigma Gamma Epsilon, 51(3): 53-60.

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Green R. 1977. Niobrarateuthis walkeri, a new species of teuthid from the Upper Cretaceous Niobrara Formation of Kansas. Journal Paleontology 51(5): 992-995. Hattin D. 1982. Stratigraphy and depositional environment of Smoky Hill Chalk Member, Niobrara Chalk, (Upper Cretaceous) of the type area, western Kansas, Kansas Geological Survey Bulletin 225, 108 p. Hoganson J. W. 2006. Dinosaurs, Sharks, and Woolly Mammoths: Glimpses of life in North Dakota’s prehistoric past. Journal of the Northern Plains, 73(1 & 2): 60 p. Larson, N. L. 2010. Fossil Coleoids from the Late Cretaceous (Campanian & Maastrichtian) of the Western Interior: 78-113, in Fuchs, D. (ed.), Proceedings of the 3rd International Symposium ColeoidCephalopods through Time, Ferrantia 59, Musée national d’hisoire naturelle, Luxembourg. Larson N.L., Jorgensen S.D., Farrar R.A. & Larson P.L. 1997. Ammonites and the other cephalopods of the Pierre Seaway. Geoscience Press, Tucson: 144 p. Logan, W. 1898. The invertebrates of the Benton, Niobrara and Fort Pierre Groups. University Geological Survey of Kansas, Topeka. Vol. 4. Paleontology. Part 1. Cretaceous: 431-518. Martin, L.D. 1990. Sea Monsters of the Midwest. Bright Child Books, 27 p. Meek F. B. & Hayden F. 1856. -Description of new fossil species of Mollusca collected by F. V. Hayden, in the Nebraska Territory: together with a complete catalogue of all the remains of Invertebrata hitherto described and identified from the Cretaceous and Tertiary formations of that region. Proceedings of the Academy of Natural Sciences, Philadelphia, 8: 256-286. Meek F.B. & Hayden F. 1860. Description of new organic remains from the Tertiary, Cretaceous and Jurassic rocks of Nebraska.

Proceedings of the Academy of Natural Sciences, Philadelphia, 12: 175-185. Miller H.W. Jr. 1957. Niobrarateuthis bonneri, a new genus and species of squid from the Niobrara Formation of Kansas. Journal Paleontology 31(5): 809-811. Miller H.W. Jr. 1968. Invertebrate fauna and environment of deposition of the Niobrara (Cretaceous) of Kansas. Fort Hays Studies, n. s., science series no.8, 90 p. Miller H.W. Jr. & Walker M.V. 1968. Enchoteuthis melanae and Kansasteuthis lindneri, new genera and species of teuthid and a sepiid from the Niobrara Formation of Kansas. Transactions of the Kansas Academy of Science, 71(2): 176-183. Naef A. 1916. Sysematische übersicht der Mediterranan Cephalopden: Pubblicazioni della Stazione Zoologica di Napoli: 11-19. Nicholls E.L. and Isaak H. 1987. Stratigraphic and taxonomic significance of Tusoteuthis longa Logan (Coleoidea, Teuthida) from the Pembina Member, Pierre Shale (Campanian) of Manitoba. Journal of Paleontology, 61(4): 727-737. Stewart J.D. 1977. Teuthids of the North American Late Cretaceous (abstract). Transactions of the Kansas Academy of Science, 79(3 & 4): p. 94. Stewart J.D. 1990. Niobrara Formation vertebrate stratigraphy: 19-30, in Bennett S. C. (ed.), Niobrara Chalk excursion guidebook. University of Kansas Museum of Natural History and Kansas Geological Survey, Lawrence. Toll R.B. 1998. The gladius in Teuthoid systematics: 55-67, in Voss N.A., Vecchione M, Toll R.B. & Sweeney M.J. (eds.), Systematics and biogeography of cephalopods, Volume 1. Smithsonian Institute Press, Washington, D.C. Whiteaves J. F. 1897. On some remains of a Sepia-like Cuttlefish from the Cretaceous rocks of the South Saskatchewan. The Canadian Record of Science, 7: 459-460.

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Beneath Wyoming’s waves: marine paleontology, Cavagelli, J.P. (ed.), Tate Geological Museum 16th Annual Tate Conference, Casper, Wyoming, June, 2010: 66-78. TABLE 1 The Western Interior Ammonite Range Zones with recognized specimens of Enchoteuthididae Upper Campanian Baculites eliasi Range Zone (lower) Baculites jenseni Range Zone Baculites reesidei Range Zone ~ 72.94 ± 0.45 Baculites cuneatus Range Zone

___________________________________________Tusoteuthis cobbani

Baculites compressus Range Zone ~ 73.52 ± 0.39 Didymoceras cheyennense Range Zone ~ 74.67 ± 0.15 Exiteloceras jenneyi Range Zone ~ 75.08 ± 0.11 Didymoceras stevensoni Range Zone Didymoceras nebrascense Range Zone ~ 75.19 ± 0.28 Middle Campanian Baculites scotti Range Zone ~ 75.56 ± 0.11 Baculites reduncus Range Zone Baculites gregoryensis Range Zone Baculites perplexus Range Zone Baculites sp. (smooth species) Range Zone Baculites asperiformis Range Zone: Baculites mclearni Range Zone Baculites obtusus Range Zone ~ 80.58 ± 0.55_____________________________________Enchoteuthis melanae Lower Campanian Baculites sp. (weak flank ribs) Range Zone Baculites sp. (smooth) Range Zone Scaphites hippocrepis III Range Zone ________________________________________Enchoteuthis melanae Scaphites hippocrepis II Scaphites hippocrepis I Scaphites leei

______________________________________________________Tusoteuthis longa? _________________________________________________Enchoteuthis melanae ?

Upper Santonian Desmoscaphites bassleri Range Zone ~ 84.30 ± 0.34__________________________________ Tusoteuthis longa Desmoscaphites erdmanni Range Zone Clioscaphites choteauensis Range Zone ______________________________________Niobrarateuthis bonneri ? Lower Santonian Clioscaphites vermiformis Range Zone Clioscaphites saxitonianus Range Zone _________________________________________Niobrarateuthis walkeri Coniacian Scaphites depressus Range Zone ~ 87.14 ± 0.39 __________________________________Kansasteuthis lindneri Scaphites ventricosus Range Zone Scaphites preventricosus Range Zone ~ 88.55 ± 0.59 All data for Ammonite Range Zones and radiometric dates in this table were taken from Cobban et al. 2006.

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