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The extinct great whites represented in the Lee Creek fauna are Cosmopolitodus hastalis and
C. xiphodon. C. hastalis is a Pungo River species. The teeth (particularly the laterals),
are similar to Isurus desori except broader with less pointed roots.
Although occasionally found in the Pungo River, Cosmopolitodus xiphodon is most common in
the lower Yorktown. and appears derived from C. hastalis. C. xiphodon teeth are similar
to those of hastalis, but the roots tend to be taller and the crown more labio-lingually compressed,
creating a wider appearance. For information on the genus see
Cosmopolitodus.
Cosmopolitodus hastalis (AGASSIZ, 1843)
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Fig. 1 - Cosmopolitodus hastalis
lingual view |
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Fig. 2 - Cosmopolitodus hastalis
unusual variation with lateral cusplets
Pungo River, slant height 33 mm |
Cosmopolitodus xiphodon (AGASSIZ,1833-1844)
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Fig. 3 - Cosmopolitodus xiphodon
lingual view of specimens |
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Fig. 4 - Cosmopolitodus xiphodon
variation reflects development of serrations
Yorktown, slant height 40 mm |
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