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Stingray
Order Rajiformes |
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Blue-spotted
fantail ray
Taeniura lymma
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The
stingray is well adapted for bottom-dwelling. Its flattened body allows
it to hover close over the sand. Its mouth is on the underside to
forage for buried bivalves, crabs and worms. These are crushed and
ground up with their blunt teeth.
Flight of ray: Stingrays have
greatly enlarged pectoral fins along their body edges. With graceful
undulations of these fins, they seem to ‘fly’ through the water. They
generally swim slowly, but can make a quick dash if they need to.
Some also use these enlarged fins to bury themselves in the sand in
an eyeblink. 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 five pairs of gill
slits on the underside of the body.
Making no bones: Stingrays are
closely related to sharks. Like sharks, the skeleton of a stingray
is made of flexible cartilage. If you want to know how cartilage feels
like, your nose and ears are made of cartilage! The stingray's teeth
are also made of cartilage but are strong enough to crush clam shells.
This is because the teeth are stiffened and braced with struts of
different types of cartilage.
The point of it: Most stingrays
have a serrated spine at the base of the whip-like tail. This can
cut deeply and introduce venom into the wound that can cause excruciating
pain. The spine is used to protect themselves and not to hunt prey.
They can replace lost spines. Stingrays, however, are not aggressive
animals and prefer to flee from danger. Most stingray injuries to
humans are the result of accidentally stepping on a stingray that
is lying harmlessly on the bottom. Beware! Stingray spines can even
penetrate through shoes!
Baby rays: Stingrays practice
internal fertilisation. Males have a pair of claspers near the pelvic
fins with grooves to introduce the sperm into the female. Most stingrays
give birth to live 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. |
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Mangrove whipray
Himantura walga
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quick
facts
20-30cm, sometimes seen in the seagrass lagoon
Classification:
Order Rajiformes
Class Elasmobranchii
Phylum Chordata |
