Smalltooth sawfish
| Smalltooth sawfish | |
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| Pristis pectinata in Georgia Aquarium, Atlanta, USA | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Chondrichthyes |
| Subclass: | Elasmobranchii |
| Order: | Pristiformes |
| Family: | Pristidae |
| Genus: | Pristis |
| Species: | P. pectinata |
| Binomial name | |
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Pristis pectinata Latham, 1794 |
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The smalltooth sawfish (Pristis pectinata), also known as the wide sawfish, is a sawfish of the family Pristidae. It is found in shallow tropical and subtropical waters in coastal parts of the Atlantic, including the Mediterranean. Reports from elsewhere are now believed to be misidentifications of other species of sawfish. This critically endangered species reaches a length of up to 7.6 metres (25 ft).
For many years, rarity of seeing a sawfish in the wild prevented scientists from collecting conclusive evidence about the use of their distinctive rostrum. This led them to falsely assume that the sawfish, like many other marine vertebrates with a “beak,” or an elongated rostrum, follow the rule that the appendage is used to either sense prey or capture prey, but never both. There are no other highly studied marine animals with similar rostral characteristics that have shown that the rostrum is used for both of these feeding techniques. Recent studies have demonstrated, however, that the sawfish utilize their rostrum to both sense and manipulate prey.
A sawfish’s saw is made up of thousands of sensory organs that allow them to detect and monitor the movements of other organisms by measuring the electric fields they emit. The sensory organs, also called ampullary pores, are packed most densely on the dorsal side of its beak. This allows the fish to create an image of the three-dimensional area above it, even in waters of low-visibility. This provides support for the bottom-dwelling behavior of sawfish. Utilizing their saw as an extended sensing device, sawfish are able to “view” their entire surroundings by maintaining a position low to the sea floor.
Sawfish uncover sand dwelling crustaceans and mollusks, two common prey types, by using their unique anatomical structure as a tool for digging and grubbing about in sand or mud. The sawfish churn up the sea bottom with their exaggerated rostrum to uncover these hidden food sources.
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Wikipedia