TOOTH VS TOOTH

Broadnose sevengillversusBluntnose sixgill

Two original visual plates. Ten comparison fields. One careful verdict.

Broadnose sevengill profile →
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.
VS
Bluntnose sixgill profile →
FRONT / LABIAL VIEWEDGE / PROFILEMIXED 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.
IDENTIFICATION VERDICT

These teeth overlap in both broad form and edge treatment. Root proportions, jaw position, size, age and locality must carry more weight than silhouette alone.

FIELD MARKBroadnose sevengillBluntnose sixgill
Signature

Lower teeth form a comb with one tall cusp and a row of progressively smaller cusps.

Wide lower tooth with a tall leading cusp followed by a comb of smaller cusps.

Crown

Comb-like / Several cusps

Comb-like / Several cusps

Edge

Smooth edge / Uneven / mixed serrations

Uneven / mixed serrations

Cusplets

Several smaller cusps

Several smaller cusps

Root

Wide / nearly flat root

Wide / nearly flat root

Tooth height

8–30 mm reference range

8–35 mm reference range

Jaw variation

Small pointed uppers and broad multi-cusped lower cutting combs.

Narrow pointed uppers and broad comb-like lower teeth.

Habitat

Temperate coastal bays, shelves and deeper offshore water.

Deep temperate and tropical slopes, canyons and seamounts.

Diet

Fishes, rays, other sharks, seals and carrion.

Fishes, rays, sharks, squid, crustaceans and carrion.

Shark size

Commonly 2–2.9 m (6.5–9.5 ft); large females may exceed 3 m.

Commonly 3–4.5 m (10–15 ft); large females may be longer.

Bite force

No reliable species-specific value is established; bite force changes with body size and bite point.

No reliable species-specific value is established; bite force changes with body size and bite point.

Fossils

Hexanchid comb teeth have an extensive Mesozoic and Cenozoic record.

Hexanchid teeth have a long Jurassic-to-Recent record.

BROADNOSE SEVENGILL TRAP

Identify a comb-like tooth to cow sharks first; exact species may still depend on locality and cusp count.

BLUNTNOSE SIXGILL TRAP

Cusp count, crown proportions and age are needed to distinguish sixgill from sevengill and fossil hexanchids.

SOURCE / Broadnose sevengillFlorida Museum
SOURCE / Bluntnose sixgillFlorida Museum

Illustrations are original TuffShark diagrams, not photographs taken from either reference.

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KEEP COMPARING

Other difficult tooth pairs.

Great white sharkversusTiger sharkOpen →MegalodonversusGreat white sharkOpen →Bull sharkversusDusky sharkOpen →Bull sharkversusOceanic whitetipOpen →