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Fossils from Monmouth County, New Jersey

Thresher (Paranomotodon angustidens)

Age – Late Cretaceous; Commonality – Uncommon; Size – ¼ – ¾ inches

Thresher shark teeth are somewhat ignored by collectors, probably because their features are worn down easily by stream action, which causes them to be mistaken for a worn goblin, porbeagle, or sand tiger. Nice threshers are hard to come by. The crown is similar to Archaeolamna kopingensis teeth. The thresher crown is less robust and is thinner on the carinae. Thresher teeth have small vestigial cusplets, which look like small bumps on the shoulders of the tooth. They are almost like extensions of the crown. The thresher roots are slightly porous and have a large nutrient groove. The anterior tooth crowns are straight and the laterals are angled distally. The upper teeth are generally flatter and less robust than the lowers.

Symphyseal Tooth

Lingual View

Thresher Shark Cretaceous (Paranomotodon angustidens) Symphyseal tooth, New Jersey

Labial View

Profile View of Mesial Side

Profile View of Distal Side

Basal View

Occlusal View

This is a rather strange tooth. It is possibly a symphyseal P. angustidens. There is also the chance that it is a positional variation of a Protolamna borodini. In my opinion it matches better with this species.

Anterior Teeth

Lingual View

Labial View

Profile View of Mesial Side

Thresher Shark Cretaceous (Paranomotodon angustidens) Anterior tooth, New Jersey

Profile View of Distal Side

Basal View

Occlusal View

This tooth is most likely an upper anterior.

Lingual View

Labial View

Profile View of Mesial Side

Profile View of Distal Side

Here is another anterior; it is probably an upper.

Lingual View

Labial View

Profile View of Mesial Side

Profile View of Distal Side

Basal View

Occlusal View

This tooth is most likely a lower anterior.

Lingual View

Labial View

Profile View of Mesial Side

Profile View of Distal Side

Basal View

Occlusal View

This tooth is either an upper first anterior or a lower anterior.

Lingual View

Labial View

Profile View of Mesial Side

Profile View of Distal Side

Another lower anterior.

Lateral Teeth

Lingual View

Labial View

Profile View of Mesial Side

Profile View of Distal Side

Basal View

Occlusal View

Lateral teeth are much more slanted than the anteriors. This one is most likely an upper.

Lingual View

Thresher Shark Cretaceous (Paranomotodon angustidens) Lateral tooth, New Jersey

Labial View

Profile View of Mesial Side

Profile View of Distal Side

Basal View

Occlusal View

Here is another possible upper lateral with a different shape.

Lingual View

Labial View

Profile View of Mesial Side

Profile View of Distal Side

Basal View

Occlusal View

Another upper lateral similar to the one above.

Lingual View

Labial View

Profile View of Mesial Side

Profile View of Distal Side

Basal View

Occlusal View

Lower laterals are more erect than the upper laterals.

Posterior Teeth

Lingual View

Labial View

Profile View of Mesial Side

Profile View of Distal Side

Thresher Shark Cretaceous (Paranomotodon angustidens) Posterior tooth, New Jersey

Basal View

Occlusal View

Posteriors are slanted like the upper laterals, but have a narrower root. This one is probably an upper.

Lingual View

Labial View

Profile View of Mesial Side

Profile View of Distal Side

Basal View

Occlusal View

This one has a somewhat unusual shape.

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