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| fishes text index | photo index |
| Phylum Chordata > Subphylum Vertebrata > fishes |
| Skates,
rays and stingrays Order Rajiformes updated Oct 08
Where seen? Elegant discs with bulbous eyes and a narrow tail, these large fishes are often seen in our mangroves, seagrass meadows and coral reefs. What are these fishes? Called skates, rays and stingrays, these fishes belong to the Order Rajiformes which includes 10 families. Those commonly seen on our shores at low tide are stingrays that belong to Family Dasyatidae. These fishes are related to sharks but most are adapted for hunting and living on the sea bottom. For simplicity, we'll refer to all these fishes as rays. Features: Rays have flattened bodies with greatly enlarged pectoral fins along their body edges. With graceful undulations of these fins, they seem to ‘fly’ through the water. Some also use these enlarged fins to bury themselves in the sand. To avoid breathing in mud and sand, water is taken in from the the upperside of their bodies through spiracles (holes) beside their eyes. The water is then expelled through gill slits on the underside of the body. The snout may function as an electroreceptive organ, sensitive to electric charges of prey buried in the ground. Stingrays have a sting on their tails (usually near where the tail joins the body, and not at the tip of the tail), while eletric rays can generate electical currents that can give you a nasty shock. So avoid handling these animals. Stingrays often hide in silty bottoms and under coral ledges, watch where you step and where you put your hand. Sometimes confused with horseshoe crabs. In murky waters, the two animals look very similar, both being round and flat with a long tail. Making no bones: Rays are closely related to sharks. Like sharks, the skeleton of rays are made of flexible cartilage. If you want to know how cartilage feels like, your nose and ears are made of cartilage! Baby rays: Rays practice internal fertilisation. Most rays give birth to live fully developed young, although some may lay eggs enclosed in a capsule. Human uses: Stingrays are a popular seafood dish in Singapore. The large pectoral fins are barbequed and served with chilli, often on a banana leaf. You can see their cartilageous bones as you eat the flesh. Blue-spotted fantail ray (Taeniura lymma) is also popular in the live aquarium trade although it does not do well in captivity. Status and threats: Our Stingrays are not listed as endangered. However, throughout its range, the Blue-spotted fantail ray (Taeniura lymma) is under pressure from over collection for the aquarium trade and destruction of its reef habitat. Like other creatures of the intertidal zone, Stingrays are also affected by human activities such as reclamation and pollution. Poaching by hobbyists and overfishing can also have an impact on local populations. |
 Blue-spotted fantail ray Kusu Island, Jul 04  Blue-spotted stingray Pulau Sekudu, Apr 06  Mangrove whipray Chek Jawa, May 03  The Numbfish can produce an electric shock Changi, Jun 05 |
They are related to sharks and have cartilage instead
of bones.| Order
Rajiformes recorded for Singapore from Wee Y.C. and Peter K. L. Ng. 1994. A First Look at Biodiversity in Singapore. *from Lim, Kelvin K. P. & Jeffrey K. Y. Low, 1998. A Guide to the Common Marine Fishes of Singapore. **our observation.
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Links
References
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The Nature Society (Singapore), Singapore. 343 pp.|
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