Rostrum (anatomy)

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The rostrum (beak) of a grey heron Kew Gardens - London - September 2008 (2952022283).jpg
The rostrum (beak) of a grey heron

Rostrum (from Latin rostrum , meaning beak ) is a term used in anatomy for a number of phylogenetically unrelated structures in different groups of animals.

Contents

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Invertebrates

Vertebrates

Diagram of a wolf skull with key features labelled Wolf cranium labelled.jpg
Diagram of a wolf skull with key features labelled

In mammals, the rostrum is that part of the cranium located in front of the zygomatic arches, where it holds the teeth, palate, and nasal cavity. [6] Additionally, the corpus callosum of the human brain has a nerve tract known as the rostrum.

The beak or snout of a vertebrate may also be referred to as the rostrum.

See also

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<span class="mw-page-title-main">Cephalopod beak</span> Body part of cephalopods

All extant cephalopods have a two-part beak, or rostrum, situated in the buccal mass and surrounded by the muscular head appendages. The dorsal (upper) mandible fits into the ventral (lower) mandible and together they function in a scissor-like fashion. The beak may also be referred to as the mandibles or jaws.

<span class="mw-page-title-main">Fish jaw</span>

Most bony fishes have two sets of jaws made mainly of bone. The primary oral jaws open and close the mouth, and a second set of pharyngeal jaws are positioned at the back of the throat. The oral jaws are used to capture and manipulate prey by biting and crushing. The pharyngeal jaws, so-called because they are positioned within the pharynx, are used to further process the food and move it from the mouth to the stomach.

<i>Atlanticopristis</i> Extinct genus of cartilaginous fishes

Atlanticopristis is an extinct genus of sclerorhynchid that lived during the Middle Cretaceous (Cenomanian) of what is now the Northeast Region of Brazil, between 100.5 and 93.9 million years ago. Fourteen fossil teeth from Atlanticopristis were found in the Alcântara Formation, and referred to the closely related Onchopristis in 2007; a redescription in 2008 by Brazilian paleontologists Manuel Medeiros and Agostinha Pereira assigned it to a new genus containing one species, Atlanticopristis equatorialis.

References

  1. Charles Drew (November 17, 2003). "Crustacea". University of Bristol. Archived from the original on July 3, 2012. Retrieved November 7, 2010.
  2. Todd A. Haney, Joel W. Martin & Eric W. Vetter (2007). "Leptostraca". In James T. Carlton (ed.). The Light and Smith Manual: Intertidal Invertebrates from Central California to Oregon (4th ed.). University of California Press. pp. 484–495. ISBN   978-0-520-23939-5. Archived from the original on 2020-09-12. Retrieved 2020-09-12.
  3. George Gordh, Gordon Gordh & David Headrick (2003). "Rostrum". A Dictionary of Entomology. CAB International. p. 792. ISBN   978-0-85199-655-4.
  4. Douglas Grant Smith (2001). "Mollusca (gastropods, pelecypods)". Pennak's freshwater invertebrates of the United States: Porifera to Crustacea (4th ed.). John Wiley and Sons. pp. 327–400. ISBN   978-0-471-35837-4. Archived from the original on 2020-09-12. Retrieved 2020-09-12.
  5. Burt Carter. "Cephalopods". Invertebrate Paleobiology. Archived from the original on 2012-04-02. Retrieved 2011-09-22.
  6. Elbroch, Mark "Animal Skulls: A Guide to North American Species", Stackpole Books 2006, p9
  7. William F. Perrin; Bernd Würsig; J.G.M. Thewissen (26 February 2009). Encyclopedia of Marine Mammals. Academic Press. ISBN   978-0-08-091993-5. Archived from the original on 2 September 2020. Retrieved 12 September 2020.
  8. "Basic anatomy of Cetaceans - Dolphins". Robin's Island. Archived from the original on November 17, 2010. Retrieved November 7, 2010.
  9. Wueringer, Barbara E.; Squire, Lyle; Kajiura, Stephen M.; Hart, Nathan S.; Collin, Shaun P. (2012). "The function of the sawfish's saw". Current Biology. 22 (5): R150–R151. doi: 10.1016/j.cub.2012.01.055 . PMID   22401891.