Order MYLIOBATIFORMES
Stingrays
Flattened batoids with pectoral fins expanded and fused
with head and trunk to form a disc; 5 or 6 gill slits; snout
angular, broadly rounded or bilobed; nasal flaps fused to
each other across the snout to form a squared-off or bilobate nasal curtain; no electric organs; one dorsal fin or
none; tail fairly thick or more or less elongate and whiplike, usually with a stinging spine near base of tail; caudal fin
small or absent, apparently of little or no use in swiming.
Ovoviviparous. Adults 15 cm to 6.7 m across the disc. A
large circumtropical and warm/temperate group of inshore,
deep-water benthic, and oceanic batoids. Four to 7 families
depending on the classification used; 21 genera and 170 or
more species.
Suborder MYLIOBATOIDEI
Stingrays, Eaglerays,
Mantas
Pylsterte, Arendroe,
Mantas
Five pairs of gill slits. Brain not greatly reduced in size.
Three to 6 families depending on the classification used;
18-20 genera, and at least 170 species.
Family No. 28: MYLIOBATIDAE
by L.J.V. Campagna
Eaglerays
Arendroe
Head, body and pectoral fins form a strongly angular
disc, nearly twice as wide as long. Head and snout strongly
marked off from rest of disc; snout forms a single lobe or a
pair of broadly rounded lobes separated by a median notch
with a bilobate shelf overhanging snout. Five pairs of gill
openings on underside of disc. Large plate-like crushing
teeth normally in 1 or 7 or 9 rows in each jaw. A moderatesized dorsal fin on tail base, and a sting behind it. No caudal
fin or finfolds; tail slender, whiplike, as long as disc or
longer.
Moderate-sized to very large batoid fishes, reaching at
least 2.3 m width and possibly even 3-4 m. Strong-swimming, flying like birds through the water with their strong
pectoral "wings" , and hence very difficult for anglers to subdue. Position of sting at base of tail makes eaglerays less
dangerous than true stingrays, but they should be handled
with care; can crush fingers or toes with their powerful jaws.
132
Pylsterte
Worldwide in tropical and subtropical waters, inshore and
well offshore. Five genera, 4 in our area, each with a single
species.
KEY TO GENERA
la Snout forming a pair of broadly rounded lobes separated
by a median notch; front part of head concave, overhanging
snout ................................................................. Rhinoptera
Ib Snout projecting as a single lobe; forehead not
overhanging snout ............................................................. 2
2a Snout broad and short, connected to pectoral disc
by a broad ridge under each eye; P tips blunt, hardly
falcate ................................................................ Myliobatis
2b Snout elongate, narrow, with narrow ridge or no ridge
under eyes to disc; P tips acutely pointed and falcate ................. 3
3a One row of tooth plates in each jaw; nasal curtain
deeply notched; white spots on dorsal surface of disc
(southern African species only) ................................. Aetobatus
3b Jaws with 7 rows of tooth plates; nasal curtain
shallowly notched; no white spots on disc ............... Pteromylaeus
Genus Aetobatus Blainville, 1820
Three or more species, 1 in our area.
28.1 Aetobatus narinari
(Euphrasen, 1790)
Spotted eagleray
Spikkel-arendrog
Raja narinari Euphrasen, 1790: 217, PI. 10 (West Indies). Aetobatis
narinari: Gilchrist & Thompson, 1911: 56. Stoasodon narinari: Smith,
SFSA No. 74*. Aetobatus narinari: Wallace, 1967: 15*; van der Elst, 1981:
49*.
Tooth plates chevron-shaped in lower jaw. V narrow.
28.1 Aetobatus narinari: 54 em wide (N. Mozambique).
Stingrays
Flattened batoids with pectoral fins expanded and fused
with head and trunk to form a disc; 5 or 6 gill slits; snout
angular, broadly rounded or bilobed; nasal flaps fused to
each other across the snout to form a squared-off or bilobate nasal curtain; no electric organs; one dorsal fin or
none; tail fairly thick or more or less elongate and whiplike, usually with a stinging spine near base of tail; caudal fin
small or absent, apparently of little or no use in swiming.
Ovoviviparous. Adults 15 cm to 6.7 m across the disc. A
large circumtropical and warm/temperate group of inshore,
deep-water benthic, and oceanic batoids. Four to 7 families
depending on the classification used; 21 genera and 170 or
more species.
Suborder MYLIOBATOIDEI
Stingrays, Eaglerays,
Mantas
Pylsterte, Arendroe,
Mantas
Five pairs of gill slits. Brain not greatly reduced in size.
Three to 6 families depending on the classification used;
18-20 genera, and at least 170 species.
Family No. 28: MYLIOBATIDAE
by L.J.V. Campagna
Eaglerays
Arendroe
Head, body and pectoral fins form a strongly angular
disc, nearly twice as wide as long. Head and snout strongly
marked off from rest of disc; snout forms a single lobe or a
pair of broadly rounded lobes separated by a median notch
with a bilobate shelf overhanging snout. Five pairs of gill
openings on underside of disc. Large plate-like crushing
teeth normally in 1 or 7 or 9 rows in each jaw. A moderatesized dorsal fin on tail base, and a sting behind it. No caudal
fin or finfolds; tail slender, whiplike, as long as disc or
longer.
Moderate-sized to very large batoid fishes, reaching at
least 2.3 m width and possibly even 3-4 m. Strong-swimming, flying like birds through the water with their strong
pectoral "wings" , and hence very difficult for anglers to subdue. Position of sting at base of tail makes eaglerays less
dangerous than true stingrays, but they should be handled
with care; can crush fingers or toes with their powerful jaws.
132
Pylsterte
Worldwide in tropical and subtropical waters, inshore and
well offshore. Five genera, 4 in our area, each with a single
species.
KEY TO GENERA
la Snout forming a pair of broadly rounded lobes separated
by a median notch; front part of head concave, overhanging
snout ................................................................. Rhinoptera
Ib Snout projecting as a single lobe; forehead not
overhanging snout ............................................................. 2
2a Snout broad and short, connected to pectoral disc
by a broad ridge under each eye; P tips blunt, hardly
falcate ................................................................ Myliobatis
2b Snout elongate, narrow, with narrow ridge or no ridge
under eyes to disc; P tips acutely pointed and falcate ................. 3
3a One row of tooth plates in each jaw; nasal curtain
deeply notched; white spots on dorsal surface of disc
(southern African species only) ................................. Aetobatus
3b Jaws with 7 rows of tooth plates; nasal curtain
shallowly notched; no white spots on disc ............... Pteromylaeus
Genus Aetobatus Blainville, 1820
Three or more species, 1 in our area.
28.1 Aetobatus narinari
(Euphrasen, 1790)
Spotted eagleray
Spikkel-arendrog
Raja narinari Euphrasen, 1790: 217, PI. 10 (West Indies). Aetobatis
narinari: Gilchrist & Thompson, 1911: 56. Stoasodon narinari: Smith,
SFSA No. 74*. Aetobatus narinari: Wallace, 1967: 15*; van der Elst, 1981:
49*.
Tooth plates chevron-shaped in lower jaw. V narrow.
28.1 Aetobatus narinari: 54 em wide (N. Mozambique).