THE SHARKS

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Extinct Requiem Shark
Physogaleus secundus (Winkler)

Age - Eocene  Commonality - Common

The Physogaleus genus first appeared in the Eocene as a small shark called Physogaleus secundus. The teeth of this species are small averaging inches (6 mm), just large enough that a few can be found using the standard inch screens. Screening with a finer meshed screen will produce significantly more specimens. Physogaleus' teeth are smaller than the tiger sharks and lack the heavy serrations associated with the tigers. The roots are bulky with a flat face that angles away from the lingual side of the tooth. There is a strong lingual protuberance and deep nutrient grove. The teeth of P. secundus show differences between male and female. The most conspicuous difference occurs in the distal serrations. The serrations on female teeth number from 3 to 5 and are uniformed, while on the male these serrations number between 2 to 3 and are uneven.
Anterior teeth tend to have a more erect crown, few if any distal cusplets, and a stronger lingual root protuberance.
 


 

Physogaleus secundus

The teeth of Physogaleus secundus are small, averaging about 1/4 inch in
length.

Monmouth County, NJ.

 


 


Physogaleus secundus anterior


 

The roots of the sharpnose are very distinctive, they have a strong
 lingual protuberance and pronounced nutrient grove.
 There is a flat face that angles away from the lingual side of the tooth. 
 


 

Left - female / Right male (labial view)
  The distal serrations on female teeth number from 3 to 6 and are uniformed,
while on the male these serrations number between 2 to 3 and are uneven.

 


 



 

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