Largetooth Cookiecutter Shark, Isistius plutodus Click to enlarge image
Largetooth Cookiecutter Shark, Isistius plutodus. I.28924-001. Image: Australian Museum
© Australian Museum

Fast Facts

  • Classification
    Species
    plutodus
    Genus
    Isistius
    Family
    Dalatiidae
    Order
    Squaliformes
    Class
    Chondrichthyes
    Subphylum
    Vertebrata
    Phylum
    Chordata
    Kingdom
    Animalia
  • Size Range
    The Largetooth Cookiecutter Shark grows to 50 cm in length.

Introduction

The Largetooth Cookiecutter Shark has a cigar-shaped body, a short conical snout and two low, spineless dorsal fins. It has a row of 19 huge teeth (proportionately the largest of any shark species) in the lower jaw. Its anteriorly placed eyes may enable binocular vision.

Identification

The Largetooth Cookiecutter Shark has a cigar-shaped body, a short conical snout and two low, spineless dorsal fins. It has a row of 19 huge teeth (proportionately the largest of any shark species) in the lower jaw. Its anteriorly placed eyes may enable binocular vision.

The species looks similar to the Smalltooth Cookiecutter Shark. The two species can be separated base on tooth size (25-32 rows in lower jaw in the Smalltooth Cookiecutter Shark), colouration and fin placement.

Distribution

This species is recorded from specimens caught in the Gulf of Mexico, off Okinawa, Japan, from the eastern Atlantic and from Australia.

The 363 mm long female shark in the image was trawled at a depth of about 100 m by the FV Teresa off Newcastle, New South Wales in 1988. It is the first record of this species from Southern Hemisphere waters. It is registered in the Australian Museum Ichthyology Collection (AMS I.28924-001).

The map below shows the Australian distribution of the species based on public sightings and specimens in Australian Museums. Click on the map for detailed information. Source: Atlas of Living Australia.



Feeding and diet

It feeds by biting pieces of muscle from the bodies of larger marine creatures.

References

  1. Compagno, L.J.V. 1984. FAO species catalogue. Vol.4, Sharks of the world. An annotated and illustrated catalogue of shark species known to date. Part I - Hexanchiformes to Lamniformes: viii, 1-250. FAO Fisheries Synopsis 125: 1-249.
  2. Garrick, J.A.F & Springer, S. 1964. Isistius plutodus, a New Squaloid Shark from the Gulf of Mexico. Copeia (4): 678-682.
  3. McGrouther, M.A. 2001. First record of the Large-tooth Cookie-Cutter Shark, Isistius plutodus from Australian waters. Memoirs of the Queensland Museum 46(2): 442.
  4. Zidowitz, H., Fock, H.O., Pusch, C. & H. Von Westernhagen. 2004. A first record of Isistius plutodus in the north-eastern Atlantic. Journal of Fish Biology. 64: 1430-1434.