Carcharopsis prototypus and the adaptations of single crystallite enameloid in cutting dentitions

• Autorzy: Duffin C. , Cuny G.
• Konferencja: Evolution and Diversity of Chondrichthyans (2008 ; Warszawa)
• Języki publikacji: EN

Abstrakty

EN

Carcharopsis is a Palaeozoic shark comprising an enameloid-covered cutting dentition comprising serrated teeth. The enameloid ultrastructure of the teeth of C. prototypus is examined for the first time and consists of a 35 [my]m thick layer of tightly compacted apatite crystallites with a maximum individual length of 0.1 [my]m. The crystallites are randomly-oriented toward the base of the enameloid layer, but assume a roughly parallel orientation higher up in the enameloid, with their long axes arranged normal to the tooth surface. The enameloid of typical hybodonts comprises a compact outer crystallite layer and a looser, bundled inner layer. The Cretaceous hybodonts, Priohybodus arambourgi and Thaiodus ruchae, by contrast, have a compact, less differentiated enameloid very similar to that of C. prototypus. This suggests that crystallite compaction is a corollary of the evolution of serrated dentitions possessing single crystallite enameloids.

Słowa kluczowe

EN

Carboniferous; Carcharopsis; Enameloid ultrastructure; Priohybodus; Thaiodus

PL

Carcharopsis; karbon; paleozoik; Thaiodus

• Wydawca: Faculty of Geology of the University of Warsaw ; Komitet Nauk Geologicznych PAN
• Czasopismo: Acta Geologica Polonica
• Rocznik: 2008
• Tom: Vol. 58, no. 2
• Strony: 181--184
• Opis fizyczny: Bibliogr. 12 poz.,

Twórcy

autor

Duffin C.

autor

Cuny G.

• 146, Church Hill Road, Sutton, Surrey SM3 8NF, England,

Bibliografia

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