TOOTH PROFILE / LIVING

Cookiecutter sharktooth identification

Large triangular lower teeth lock into a saw-like band; tiny upper teeth act mainly as hooks.

LivingIsistius brasiliensisLiving; fossil occurrence uncommon
FIELD VERDICT

Large triangular lower teeth lock into a saw-like band; tiny upper teeth act mainly as hooks.

Loose lower teeth are distinctive as a group but can lose their original position after separation.

01

ORIGINAL VISUAL PLATE

Front, edge and jaw position.

FRONT / LABIAL VIEWEDGE / PROFILESMOOTH EDGEPOSITION CHANGES SHAPE● ANTERIOR● LATERALTUFFSHARK ORIGINAL TOOTH PLATEDIAGRAMMATIC · NOT TO SCALE
Original TuffShark vector illustration. Trait emphasis is diagrammatic; it is not a specimen photograph or a substitute for an associated jaw.
02

IDENTIFICATION TRAITS

What to inspect.

Crown shape
Broad triangle or Narrow dagger
Cutting edge
Smooth edge
Side cusplets
No side cusplets
Root
Wide / nearly flat root
Reference tooth height
About 314 mm, depending on age and jaw position
Jaw variation
Tiny upper hooks contrast with oversized interlocking lower blades.
03

ECOLOGY + SCALE

The shark behind the tooth.

Habitat
Tropical and subtropical deep ocean, migrating upward at night.
Diet
Tissue plugs from large fishes and marine mammals, plus squid and small prey.
Estimated shark size
Usually 0.4–0.55 m (16–22 in).
Bite force
No reliable species-specific value is established; bite force changes with body size and bite point.
Fossil occurrence
Rare small teeth and connected lower tooth rows occur in younger deposits.
Time range
Living; fossil occurrence uncommon
04

FUNCTION

Form follows feeding.

The lower row is shed as a connected unit and removes plugs of tissue by suction and twisting.

05

LOOKALIKES

Do not stop at the first match.

LivingGreenland sharkSmall narrow upper teeth and broader, strongly oblique lower teeth that form a continuous cutting edge.Compare visual profile →
RELATED FORMKitefin sharkUse jaw position, locality, age and associated teeth to test this lookalike.
AUTHORITATIVE REFERENCE

Florida Museum

The visual plate is original TuffShark artwork and is not copied from the reference. Use the source alongside formation age, locality and associated material.

Open source ↗
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