The sclerorhynchids (extinct family of pristid-like sawfishes) are known from skeletons as well as teeth and rostral spines; the ptychotrigonids have been reported on the basis of oral teeth with a few speculations as to rostral spines (Case 1987, Kriwet 1999 & Manning 2006, Bourdon et al 2011). Cappetta (pers. com. 2009) is not convinced of this connection, suggesting another taxon with very small oral teeth that have not been found. Ptychotrygon oral teeth have been reported from Europe, North Africa and particularly, North America. The design of the crown and root strongly point to as the proper family.
North American Record
Many species have been described from Late Cretaceous waters of eastern, gulfian and interior North America, particularly Texas, Some of the more relevant / recent papers include:
Leriche (1940) erected Raja texana for a single tooth from the Midway Fm (Paleogene, ?reworked), Bastrop Co., TX; the images (1942 pl 1 fig 5) were ambiguous but appear to represent a high-domed crown lacking transverse ridges on the labial face. Welton & Farish (1993: 150) included this tooth-design as Ptychotrygon texana with specimens not particularly close. In addition to a questionable horizon and poor description, Chandler (1921) had already used Raja texana for an extant skate -- it will not be deemed valid on this webpage.
McNulty & Slaughter (1972: 650) erected P. hooveri for a tooth-design (labial face lacking transverse ridge) from the Turonian of Texas (subsequently moved to Texatrygon).
Cappetta (1973a) erected P. ledouxi from the Turonian of South Dakota.
Meyer (1974: 113-137) reported or described multiple taxa in his unpublished thesis:
- P. triangularis (REUSS 1845)
(p115-117, fig. 31); Turonian-Coniacian of Texas; (synonymized P. ledouxi into triangularis)
- P. t. eutawensis (p118-120, fig. 32); Santonian, Mississippi; later described by Case et al (2001) as P. eutawensis
- P. aff triangularis (p121, fig. 33); Santonian-Maastrichtian, Mississippi;
- P. hooveri (p122-124, fig. 34); Turonian-Coniacian, TX; CC1999 moved to Texatrygon
- P. aff hooveri (p124-125, fig. 35); Sant., MS; likely Erguitaia benningensis of Case et al (2001)
- P. mcnultii (p126-127, fig. 36); Ceno., TX; CC1999 include as P. slaughteri
- P. ritchiei (p128-132, fig. 37-8); Turonian, Texas; CC1999 include figured specimens as I. schneideri (37b) and Kiestus texanus (37a).
- P. palaeformis (p132-135 fig. 39); Sant., MS; looks Ischyrhiza mira.
- P. sp or S sp (p136-137 fig. 40 ; ?Campanian, Texas; figure looks Borodinopristis or Sclerorhynchus.
Cappetta & Case (1975a: 32-35, fig 9, pl 4.23-28) reported P. triangularis and erected P. cuspidata from the Late Cretaceous of New Jersey. Later that year, Cappetta (1975b) erected P. vermiculata for those New Jersey teeth previously included as P. triangularis.
Cappetta & Case (1975b: 396, fig 5) erected P. slaughteri from the Cenomanian of Texas.
Schwimmer (1986: 121 plate 1:f) depicts a specimen (Campanian, GA) of the P. vermiculata-design.
Cappetta (1987:156-57) included in the NA inland sea:
P. agujaensis MCNULTY & SLAUGHTER, 1972 (Campanian),
P. blainensis CASE 1978 from the Judith River of Montana,
P. hooveri (Cenomanian-Coniacian),
P. ledouxi CAPPETTA 1973 from the Carlile Shale of South Dakota.
P. slaughteri (Cenomanian, TX), and
P. vermiculata (Campanian, NJ)
Case (1987) erects three species from the Late Campanian of Wyoming: Ptychotrygon boothi, ellae and greybullensis.
Williamson et al (1989) reports P. triangularis from the Santonian of New Mexico
Welton and Farish (1993: 147-51) included in the Texas fauna:
P. agujaensis (Campanian),
P. hooveri (Cenomanian-Coniacian),
P. slaughteri (Cenomanian),
P. texana (Maastrichtian), and
P. triangularis (Cenomanian-Maastrichtian).
Williamson et al (1993:462) included P. triangularis (fig. 12) in the middle Turonian of Arizona and noted its presence in the Cenomanian, Turonian, and Santonian marine deposits of New Mexico (Wolberg, 1985; Lucas et al., 1988 and Williamson et al., 1989). They went on to erect P. rubyae (fig 13) for a lateral tooth-design from the Calcareous shale member, Mancos Shale, (MNA locality 989, unit 33).
Case & Cappetta (1997: 150-51) included P. vermiculata as present in the Kemp Clay (Maastrichtian, TX); in doing so, they synonymized the teeth depicted in Welton & Farish (1993: 150, fig 1-3) as P. texana. They went on to erect P. winni for a second tooth-design in the fauna. However, W&F's Figure 1 differs from the other two and compared better with C&C's new P. winni. The multitude of problems associated with P. texana (stratigraphic origin, no additional specimens from the locale, poor description and ambiguous images) would be good arguments for abandoning that name in favor of P. winni for that tooth-design.
Hartstein et al (1999: 18) included P. vermiculata from the Severn Fm (Maastrichtian) of Maryland; from the illustration, it is difficult to see the characteristic multiple transverse edges associated with P. vermiculata. [Included herein as figure is a Severn example referred to as Ptychotrygon sp B which does not compare well with P. vermiculata].
Cappetta & Case (1999: 39-40) included from the Albian-Campanian of Texas:
P. aff blainensis (Lower Campanian; in so doing synonymized Case's P. boothi),
P. slaughteri (Cenomanian) and
P. triangularis (Turonian-Coniacian)
In addition, the authors erected a new genus Texatrygon and moved to it hooveri and greybullensis.
Case et al (2001) erected from the Santonian of Georgia:
P. chattahoocheensis (pg 95, pl. 5, fig 105-109) and
P. eutawensis (pg 96, pl. 5, fig 110 & pl. 6, figs 111-113, text fig. 6). They included as P. cf triangularis (pg. 96, pl. 6, fig 114-15) two specimens that might represent more distal positions of P. eutawensis. They also included a rostral denticle (pg 97, pl. 6, fig. 118-19) as Ptychotrygon sp.
Beker et al (2004: 788, fig. 5h–l) reported Ptychotrygon cf. P. vermiculata from the Fox Hills Formation (Maastrichtian), Meade County, South Dakota.
Kriwet (2004) wrote that using cladistic principles and phylogenic analysis, appeared to represent a sister group to the Pristiformes and proposed the order Sclerorhynchiformes. Certain taxa (Ptychotrygon, Celtipristis, Texatrygon & Kiestus) deemed Rajiformes incertae sedis by Cappetta (1987), Cappetta & Case (1999) and Kriwet (1999b), were included in Sclerorhynchiformes. Kriwet et al. (2009) would move that latter group to a newly erected .
Beker et al (2010: 261) reported P. triangularis from the Mancos Shale (Middle Turonian) of Emery and Carbon Counties, Utah.
Bourdon et al (2011: 43) reported P. eutawensis from the Santonian of New Mexico.
Hamm & Cicimurri (2011:120) included P. triangularis (in the family ) from the Atco Formation (Early Coniacian) of Texas.
Neither Case (1979) nor Robb (1989) included Ptychotrygon in their North Carolina faunal lists (where it is abundant).
The teeth of this genus are usually small (2 - 6 mm in width), laterally expanded with a transverse crest, strong labial visor and often bearing additional transverse ridges on the labial crown face. The roots are bilobate (triangular when viewed basally) with a nutrient groove, central foramen, and a lateral foramen on the lingual face of each lobe.
As noted above and in the rostral discussion, it is the website's opinion that Ptychotrygon had rostral denticles and when their oral teeth are abundant, rostral spines should be present as well. In North Carolina (pers. obs.) and New Mexico (Bourdon et al 2011) this oral tooth - rostral spine relationship resulted in the assignments for P. eutawensis (Figs. - ) and P. vermiculata (Figs. - ) below.
In 1998 I had the opportunity to collect and study some 175 Ptychotrygon teeth from the Black Creek sands of Lenoir Co., North Carolina. Although individual teeth would vary, largely because of tooth position (Fig. ) and possibly as a result of sex and age, most corresponded with the P. vermiculata design. Using these as an example, a moderately strong transverse crest is accompanied by two additional transverse ridges on the labial face and another, high on the lingual face. A strong labial visor is accompanied by a corresponding depression on the lingual face of the crown. In a median position, the occlusal surface of the visor has ornamentation, which appears as short, meandering enameloid ridges. On some teeth, small enameloid "bumps" may be present in the depressions created by the transverse ridges of the labial face. The roots are less than half the height of the crown, and each lobe is clearly triangular when viewed basally. The nutrient groove is strong and bears a large central pore. Viewed lingually, a lateral foramen is on each lobe.
Follow-up collecting (2007) of reworked Late Cretaceous (Peedee/Tar Heel Fm) material in Wayne Co., NC provided additional specimens with a greater diversity. One of these additional tooth-designs compared very well with P. cuspidata (Fig. ). This specimen has a high crown connected to the lateral margins with a typical transverse edge; atypically, a relatively sharp medial ridge extends to the center of the prominent labial visor. The lower portion of the labial crown face bears numerous enameloid ridges extending partially up the crown face or to the medial ridge. A third design, Ptychotrygon sp A (fig. & ) is represented by several teeth. It is differentiated from P. vermiculata by its lateral profile and less-ridged labial face; it lacks the lower ornamentation seen in P. cuspidata.
Becker, M.A., Chamberlain, J.A., jr., and Terry, D.O., 2004. Chondrichthyans from the Fairpoint Member of the Fox Hills Formation (Maastrichtian), Meade County, South Dakota. Journal of Vertebrate Paleontology, 24:780–793.
Becker, M.A., Wellner, R.W., Mallery, C.S., jr. and Chamberlain, J.A., jr., 2010. Chondrichthyans from the lower Ferron Sandstone Member of the Mancos Shale (Upper Cretaceous: Middle Turonian) of Emery and Carbon Counties, Utah, USA; Journal of Paleontology, 84(2): 248–266.
Bourdon, J., Wright, K., Lucas, S.G., Spielmann, J.A. and Pence, R., 2011. Selachians from the Upper Cretaceous (Santonian) Hosta Tongue of the Point Lookout Sandstone, central New Mexico. New Mex. Mus. Nat. His. and Sc., Bulletin 52; 54pp.
Cappetta, H., 1973a. Selachians of the Carlile Shale (Turonian) of South Dakota: Journal of Paleontology, v. 47, p. 504-514.
Cappetta, H., 1987. Chondrichthyes II. Mesozoic and Cenozoic Elasmobranchii. In: Handbook of Paleoichthyologie, vol. 3b, Gustav Fischer Verleg, Stuttgart, 193 pp.
Cappetta, H. 1975. Ptychotrygon vermiculata n. sp., sélacien nouveau du Campanien du New Jersey. Comptes Rendus Sommaires de la Société Géologique de France 17:164-166.
Cappetta, H. and G. Case, 1975a. Contribution à l'étude des sélaciens du groupe Monmouth (Campanien - Maestrichtian) du New Jersey. Palaeontographica Abteilung A, 151:1-46.
Cappetta, H. and G. Case, 1975b. Sélaciens nouveaux du Crétacé du Texas. Géobios, 8 (4): 303-307, 6 figs.
Cappetta, H. and G. Case, 1999. Additions aux faunes de sélaciens du Crétacé du Texas (Albien supérieur-Campanien). Palaeoichthyologica, 9, 5-111.
Case, G., 1979. Cretaceous Selachians from the Peedee Formation (Late Maestrichtian) of Duplin County, North Carolina, Brimleyana, Vol 2, pp 77-89.
Case, G., 1987. A new selachian fauna from the Late Campanian of Wyoming (Teapot Sandstone Member, Mesaverde Formation, Big Horn Basin) Palaeontographica Abteilung A, v. 197, p. 1-37.
Case, G. and H. Cappetta. 1997. A new selachian fauna from the late Maastrichtian of Texas. Münchener Geowissenschaften Abhandungen 34:131-189.
Case, G, D. Schwimmer, P. Borodin and J. Leggett, 2001. A new selachian fauna from the Eutaw Formation (Upper Cretaceous/Early to Middlew Santonian) of Chattahoochee County, Georgia. Palaeontographica Abt. A, 261:83-102.
Chandler, A., 1921. A new species of ray from the Texas coast, and report of the occurrence of a top minnow new to the fauna of eastern Texas. Proceedings of the United States National Museum v. 59 (no. 2393): 657-658.
Hamm, S.A. and D.J. Cicimurri, 2011. Early Coniacian (Late Cretaceous) selachian fauna from the basal Atco Formation, Lower Austin Group, north central Texas; Paludicola [Rochester Institute of Vertebrate Paleontology] 8(3):107-127.
Hartstein, E., L. Decina and R. Keil, 1999. A Late Cretaceous (Severn Formation) Vertebrate Assemblage from Bowie, Maryland. The Mosasaur, 6:17-23.
Kriwet, J., 1999. Ptychotrygon geyeri n. sp. (Chondrichthyes, Rajiformes) from the Utrillas Formation (Upper Albian) of the central Iberian Ranges (East-Spain): Profil, v. 16, p. 337-346.
Kriwet, J., 2004. The systematic position of the Cretaceous sclerorhynchid sawfishes (Elasmobranchii, Pristorajea) In: Mezozoic Fishes 3 - Systematics , Palaeoenvironments and Biodiversity. Arratia & Tintori (eds.); Pfeil, Germany. pp 57-73.
Kriwet, J., Nunn, E. and Klug, S., 2009. Neoselachians (Chondrichthyes, Elasmobranchii) from the Lower and lower Upper Cretaceous of north-eastern Spain. Zoological Journal of the Linnean Society, 2009, 155, 316-347, 12 figures
Leriche, M., 1940. Le synchronisme des formations éocènes marines des terraines des côtés l'Atlantique d'après leur faune icthyologique. C.R.Acad. Sci. Paris, 210: 589-592 & 648-649.
Lucas, S., B. Kues, S. Hayden, B. Allen, K. Kietzke, T. Williamson, P. Sealey, and R. Pence, 1988. Cretaceous stratigraphy and biostratigraphy, Cooke's Range, Luna County, New Mexico. New Mexico Geological Society, Guidebook, 39:143-167.
Meyer, R., 1974. Late Cretaceous elasmobranchs from the Mississippi and East Texas embayments of the Gulf Coastal Plain. Unpubl. PhD dissertation, Southern Methodist Univ., Dallas, xiv+419 p.
Manning, E., 2006. Late Campanian vertebrate fauna of the Frankstown site, Prentiss County, Mississippi; systematics, paleoecology, taphonomy, sequence stratigraphy. Unpub. PhD dissertation, Tulane Univ., New Orleans, xvii+419 p., 16 pls.
McNulty and B. Slaughter, 1972. The Cretaceous selachian genus, Ptychotrygon JAEKEL 1894. Eclogae geol. Helv., 65(3):647-656, fig. 1-2, pl 1.
Robb, A., 1989. The Upper Cretaceous (Campanian, Black Creek Formation) Fossil Fish Fauna of Phoebus Landing, Bladen County, North Carolina, The Mosasaur, Vol 4, pp 75-92.
Schwimmer, D., 1986. Late Cretaceous fossils from the Blufftown Formation (Campanian) in western Georgia. The Mosasaur. Delaware Valley Paleontological Society. pp 109-119.
Welton, B. and Farish, R., 1993. The Collector's Guide to Fossil Sharks and Rays from the Cretaceous of Texas. Before Time, Texas. 204 pp.
Williamson, T., S. Lucas,and R. Pence, 1989. Selachians from the Hosta Tongue of the Point Lookout Sandstone (Upper Cretaceous, Santonian), Central New Mexico. New Mexico Geological Society Guidebook, 40: 239-245.
Williamson, T., J. Kirkland and S. Lucas, 1993. Selachians from the Greenhorn cyclothem ("Middle" Cretaceous: Cenomanian-Turonian), Black Mesa, Arizona, and the paleogeographic distribution of Late Cretaceous selachians. Journal of Paleontology 67(3), pp 447-474.
Wolberg, D., 1985. Selachians from the Late Cretaceous (Turonian) Atarque Sandstone Member, Tres Hermanos Formation, Sevilleta Grant, Socorro County, New Mexico. New Mexico Geology, 7:1-7.