Organism · Cartilaginous fishes
Hemipristis serra
Source time context (not species duration) · ≈ 23–5.33 Ma
Inferred life reconstruction
Hemipristis serra
Overview
Hemipristis serra is a fossil shark readily remembered by teeth with large serrations. Small teeth survive more often than its once-swimming body, revealing its presence. Following their shapes raises questions about the ancient shark’s diet.[1]
Loading illustration…
Key facts
Even one shark’s mouth contains differently shaped teeth. This species’ broad upper teeth bear large serrations and tips curving gently backward. Compared with slender, pointed anterior teeth, they suggest roles in grasping and cutting.[1][2]
Time and place
It is also known from layers of the Miocene, approximately 23–5.3 million years ago. The Calvert Formation and Popes Creek in Maryland, United States, are among localities reporting its teeth. Fossil sites on land today reveal sharks of ancient seas.[1]
The time range describes source context, not the complete duration of this species.
Size, form and skeleton
Broad upper teeth and prominent serrations are recognizable features. Maryland material also includes descriptions of anterior teeth 3–4 cm in total height. Comparing the size and position of a tooth helps explore why shapes differed within the same mouth.[1]
Loading illustration…
Habitat and reproduction
A living relative in the same genus is known as a coastal shark that feeds on fish and other prey. Pointed lower teeth and blade-like upper teeth suit grasping and cutting food. This comparison links fossil shark teeth to questions about life.[2]
Fossil discovery
Maryland Geological Survey material recorded tooth shapes through comparisons from the front, back, and sides. Specimens held in several museums sustain research on this ancient shark. Well-preserved teeth, rather than a large skeleton, are the focus of its discovery story.[1]
References
Research questions
Where in the mouth did an isolated tooth belong? Shapes vary between upper and lower jaws and front and rear positions, requiring several specimens to be compared. Classifying fossil sharks begins with reading these differences rather than simply the sharpness of one tooth.[1][2]
Observation
Examine the tooth tip, serrations along the edges, and root shape in sequence.[1]
Related organisms
Otodus megalodonCartilaginous fishesSource time context (not species duration) · ≈ 66–0 MaDifferent bodies among sharks
Compare the bodies of Hemipristis serra and megalodon. Hemipristis serra: a fossil shark readily remembered by teeth with large serrations. Megalodon: a gigantic shark that lived in Cenozoic seas.