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| SCIENTIFIC
CLASSIFICATION |
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| COMMON
NAME: |
ray,
stingray |
| KINGDOM: |
Animalia |
| PHYLUM: |
Chordata |
| CLASS: |
Chondrichthyes |
| SUPERORDER: |
Batoidea |
| ORDER: |
Myliobatiformes |
| FAMILY: |
Dasyatididae
(stingrays); Myliobatidae (eagle rays); Mobulidae
(manta rays) |
| GENUS
SPECIES: |
Approximately
480 species |
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| DESCRIPTION: |
Rays
in the order Chondrichthyes are essentially a compressed,
flattened shark. The pectoral fins are fused to
the head region into a disc and, in many species,
the head is raised above the disc. Most species
have a long, whip-like tail and many possess at
least 1 venomous spine located along the tail. On
the head region, large openings or spiracles lie
behind the smaller eyes and 5 gill slits are located
ventrally on each side. |
| MALE |
Male
rays are easily distinguished from females by the
presence of a pair of claspers (cigar shaped organs). |
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| SIZE: |
A
ray's wingspan, or disc-size, can range from
about 30 cm (12 in.) in yellow stingrays to over
6.1 m (20 ft.) in manta rays. |
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| DIET: |
Rays
primarily feed on mollusks, crustaceans, worms,
and occasionally smaller fishes. Manta rays filter
feed mostly on small crustaceans and small schooling
fish. |
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| GESTATION: |
Ovoviviparous
("egg live birth") |
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| RANGE: |
Worldwide,
particularly in tropical, sub-tropical, and temperate
waters |
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| HABITAT: |
Oceans,
estuaries, freshwater streams, lagoons, lakes, shallow
offshore waters, and coastlines |
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| POPULATION: |
GLOBAL |
No
data |
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| STATUS: |
IUCN |
Spotted
eagle ray and manta ray listed as Data Deficient;
several stingray species listed (1 species Endangered,
1 species Vulnerable, 1 species Lower Risk/Near
Threatened) |
| CITES |
Not
listed |
| USFWS |
Not
listed |
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| 1. |
All
rays belong to the superorder Batoidea, which
includes stingrays, electric rays, skates, guitarfish,
and sawfish. Like sharks - their close relatives
- batoids have skeletons made of tough connective
tissue called cartilage.
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| 2. |
Some
rays crush their prey between their blunt teeth,
sometimes referred to as bony plates. (The term
"bony plates" is, however, a misnomer
in that rays do not have bone, but rather, cartilage.)
Often completely burying themselves in the sand
or soft sediment, rays are camouflaged by a grayish-brown,
often mottled coloration. |
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| 3. |
Reminiscent
of birds in flight, some rays gently flap their
enlarged pectoral fins, or "wings," to
"fly" through and sometimes even leap
out of the water. The wingspan, or disc-size, of
a southern stingray (Dasyatis americana)
can reach up to 1.5 m (5 ft.). |
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| 4. |
Among
the best known rays are stingrays, which have long,
slim, whiplike tails armed with serrated, venomous
spines. A stingray lashes its tail only as a defensive
measure when it is caught, stepped on, or otherwise
disturbed. |
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| 5. |
When
wading in shallow waters, people should shuffle
their feet to avoid stepping on a buried stingray. |
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| 6. |
For
more information about rays, explore the sharks
& rays info book. |
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| In
many parts of the world, some rays are commercially
important food sources, yet currently, rays are
not considered threatened or endangered. Due to
humankind’s impact on the marine environment,
however, concern is mounting for the future of rays
throughout their range. |
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| Burgess,
W. and H.R. Axelrod. Pacific Marine Fishes. Book
4. Neptune City, NJ. T.F.H. Publications, Inc.
Ltd. 1974. |
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Eschmeyer, W.N., Herald, E.S. and H. Hammann. Peterson
Field Guide to Pacific Coast Fishes. New York.
Houghton Mifflin Co. 1983. |
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http://www.fishbase.org/
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