> Subphylum Vertebrata > fishes
rays and stingrays
learn only 3 things about them ...
They are related to sharks and have cartilage instead
They give birth to live young.
will not sting unless you step on them. Watch your step!
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
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.
Rajiformes recorded for Singapore
Wee Y.C. and Peter K. L. Ng. 1994. A First Look at Biodiversity
*from Lim, Kelvin K. P. & Jeffrey K. Y. Low, 1998. A Guide to the
Common Marine Fishes of Singapore.
Dasyatidae (Stingrays) with list of species recorded
*Family Gymnuridae (Butterfly rays)
Myliobatidae (Eagle, cownose and manta rays) with list
of species recorded for Singapore
Rhinidae (Stavenose rays)
*Rhinobatus djiddensis (White-spotted guitarfish)
- Wee Y.C.
and Peter K. L. Ng. 1994. A First Look at Biodiversity in Singapore.
National Council on the Environment. 163pp.
- Ng, P. K.
L. & Y. C. Wee, 1994. The
Singapore Red Data Book: Threatened Plants and Animals of Singapore.
The Nature Society (Singapore), Singapore. 343 pp.
- Allen, Gerry,
Fishes of South-East Asia: A Field Guide for Anglers and Divers.
Periplus Editions. 292 pp.
- Kuiter, Rudie
H. 2002. Guide
to Sea Fishes of Australia: A Comprehensive Reference for Divers
New Holland Publishers. 434pp.
Ewald and Robert Myers. 2001. Coral
Reef Fishes of the World
Periplus Editions. 400pp.
- Lim, S.,
P. Ng, L. Tan, & W. Y. Chin, 1994. Rhythm of the Sea: The Life
and Times of Labrador Beach. Division of Biology, School of
Science, Nanyang Technological University & Department of Zoology,
the National University of Singapore. 160 pp.