Carcharias cuspidata, Oligocene Boom Clay

In Belgium, Carcharias cuspidata is rarely found in the early Oligocene: at the phosphoritic base of the Boom Clay (early Rupelian) and in the Boom Clay itself (late Rupelian). In contrast, Carcharias acutissima is by far the most frequently found larger species in these deposits.
Associated tooth sets of Carcharocles angustidens, Cosmopolitodus flandricus, and Carcharias acutissima... were uncovered in the Belgian Boom Formation (Leriche, 1910), but unfortunately none of Carcharias cuspidata. In 1990 however, a unique associated tooth set was found in the Middle Oligocene of the Winterswijk region in the Netherlands (van den Bosch & Oosterink, 1991); unfortunately this set was never published in detail.
In the German Mainzer basin Carcharias cuspidata is regularly found (von der Hocht, F., 1978; Reinecke et al, 2001), while it's the most common larger species (more than C. acutissima) in the Leipzig region (Freess, 1992). It also regularly occurs in the sandy French Stampian (= Rupelian) (Leriche, 1910).

Agassiz (1843: 290 + pl.37a, fig.43-50) described the species Lamna cuspidata for the first time, using specimens from the Molasse suisse (the Miocene of Switzerland). Agassiz also noted that a series of teeth from Flonheim (Rupelian, Mainzer Basin, Germany) belong to the same species. The tooth Agassiz figured as n°47 is still accessible in the collection of the museum in Neufchatel, Switzerland, and appears to be composed of pieces from different specimens (pers. comm. von der Hocht 2006).

Leriche (1910: plate XV) figured the different tooth positions using isolated specimens collected from the Boom Formation in Belgium. He figured almost identical teeth for both the UA1 and LA1 positions, half as large as the other corresponding anterior teeth, a compressed root and very tiny cusplets. The second lower anterior has a very thick protuberance and may be the largest tooth in the jaw. The upper jaw consisted of three (regular) anterior teeth.
Leriche also figured (suspicious) intermediary teeth, similar in size as the above teeth. Extant odontaspids do have small intermediate teeth, but such teeth were not found in our sample Belgian Oligocene C. cuspidata teeth. However in the German Mainzer Basin this species is more common; intermediary teeth that can be attributed to C. cuspidata were found (see picture below). These teeth closely resemble those of C. taurus and Striatolamia.

C. cuspidata first appears in the fossil record during the Priabonian, late Eocene; later it disperses widely (Malyshkina, 2004). This species survived into the Miocene (Cappetta, 1987).

The teeth are large and robust. Carcharias cuspidata is the largest member of the Neogene Odontaspididae with Oligocene anterior teeth (in my collection) of 50mm in height. The crown is entirely smooth. The cutting edges are complete with some exceptions. Anterior teeth have relatively short root lobes and small, but sharp cusplets. The root is massive with a thick protuberance (can be very strong in lower anteriors) and a very large nutrient groove.
Lateral teeth have a flatter root, more obtusely splayed root lobes and a strong nutrient groove. Upper lateral teeth are distally inclined while lower laterals are straighter or only slightly inclined. Typical for the lateral teeth is the diversity of the cusplets; being sharp and high, triangular, or low and serrated. Sometimes small serrations can be observed at the base of the cutting edge of the crown (as seen in Palaeohypotodus and Jaekelotodus). The cutting edge, which is complete, can form a (serrated) bridge with the cusplets: tiny cusplets connecting the crown's cutting edge with one broad and triangular cusplet. Sometimes the cusplets are no more than a prolongation of the cutting edge. Regularly they bend towards the crown.

Agassiz (1843: 291 + pl.37a, fig.51-53) gave these typical lateral teeth the name Lamna denticulata. He noted however the similarity between denticulata and cuspidata and also that both species were found in the Oligocene and Miocene. Le Hon (1871: 5) already made the suggestion that Agassiz' Lamna denticulata most probably are teeth from the middle part of the upper jaw of Lamna cuspidata. At the base of the Rupelian in Belgium a large set of cuspidata teeth was collected in this limited faunal assemblage; this homogeneous set shows both Agassiz' cuspidata and denticulata types. In addition, Leriche (1910: plate XV, fig.1-21) figures both types as C. cuspidata.

Where this species fits in the Carcharias evolution is not yet fully understood. It's probably the ancestor of Carcharias vorax (Le Hon, 1871), both having the same typical lateral teeth.

All figured specimens, except for the last, were found in the Early Oligocene, Early Rupelian, Base Boom Clay (NP23) in Belgium.

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Agassiz, L. Recherches sur les poissons fossiles (1833-43), TOME III, Imprimerie de Petitpierre, Neuchâtel (Suisse).
Cappetta, H. (1987) Chondrichthyes II. Mesozoic and Cenozoic Elasmobranchii. Handbook of Paleoichthyologie, vol. 3b, Gustav Fischer Verleg, Stuttgart, 193 pp.
Cunningham, S. (2000) A comparison of isolated teeth of early Eocene Striatolamia macrota (Chondrichthyes, Lamniformes), with those of a recent sand shark, Carcharias taurus. Tertiary Research 20(1-4): 17-31.
Freess, W.B. (1992) Haie, Rochen und Chimären aus dem mitteloligozänen Meeressand von Leipzig. Aufschluss 43, pp. 195-214, Heidelberg.
Leriche, M. (1910) Note sur les Poissons stampiens du Bassin de Paris. Annales de la Société Géologique du Nord (39).
Leriche, M. (1910) Les Poissons Oligocènes de la Belgique. Mémoire du Musée Royal d'Histoire Naturelle de Belgique, 363pp.
Le Hon, H. (1871) Préliminaires d'un mémoire sur les Poissons Tertiaires de Belgique. Brussels. 15pp.
Malyshkina, T. (2004) Elasmobranchii of the Western Part of the West Siberian Palaeogene Basin, their stratigraphic and palaeographic significance. 25 pp., Ph.D. lecture, Institute of Geology and Geochemistry of the Ural Branch of the Russian Academy of Science, Ekaterinburg.
Reinecke, T., Stapf, H. & Raisch, M. (2001) Die Selachier und Chimären des Unteren Meeressandes und Schleichsandes im Mainzer Becken (Rupelium, Unteres Oligozän). Palaeo Publishing and Library, Palaeontos 1.
Siverson, M. (1999) A new large lamniform shark from the uppermost Gearle Siltstone (Cenomanian, Late Cretaceous) of Western Australia in Transactions of the Royal Society of Edinburgh: Earth Sciences (90), pp. 49-66.
van den Bosch, M. & Oosterink, H.W. (1991) Een vondst van een grote haai, Synodontaspis cuspidata in het Oligoceen van Winterswijk in Grondboor en Hamer (august 1991).
von der Hocht, F. (1978) Bestandsaufnahme der Chondrichthyes-Fauna des Unteren Meeressandes im Mainzer Bequen. Meded. Werkgr. Tert. Kwart. Geol., Vol.15(3)
von der Hocht, F. (1978) Verbreitung von Chondrichthyes-Arten im Rupelium des Mainzer Beckens und im Chattium von Norddeutschland. Meded. Werkgr. Tert. Kwart. Geol., Vol.15(4)

		First upper anterior (UA1) H=24mm © F. Mollen - 2007

			2nd upper anterior (UA2) H=30mm - Collection G. Marien -


		3rd upper anterior (UA3) H=35mm

		3rd upper anterior (UA3) H=24mm


		Lower anterior H=45mm



			Lower anterior H=49mm

		Lower anterior H=35mm


Upper lateral - H=26mm	Upper lateral - H=16mm

		Lower lateral H=15mm

		Upper posterior W=11mm


© F. von der Hocht - 2007 Carcharias cuspidata intermediate teeth - labial views Oligocene, Rupelian, Alzey Fm., Weinheim, Mainzer Basin, Germany Specimens between 8 to 13mm high.