Order RAJIFORMES
Guitarfishes & Skates
Thick-bodied or greatly flattened batoids with pectoral
fins variably expanded and fused with head and trunk.
Snout usually angular, sometimes broadly rounded. Nasal
flaps not fused to each other across the snout in our species.
No electric organs, or a slender pair in tail. Usually 2 dorsal
fins, one or none in a few genera; tail thick or relatively
slender, without a sting; caudal fin large or variably reduced.
Oviparous or ovoviviparous. The largest group of batoids,
with 3 to 7 families according to the classification used.
Suborder RAJOIDEI
Skates
Roe
Flattened batoids with pectoral fins greatly expanded and
fused with head and trunk to form a disc. Nostrils close to
mouth, with nasal flaps expanded posteriorly to overlap
mouth. A pair of small slender electric organs usually
present in tail. Pelvic fins with anterior ends expanded as
distinct lobes, these sometimes entirely separate from posterior lobes. Usually 2 small dorsal fins (sometimes absent)
close to tail tip; tail slender but not whip-like, with a
reduced caudal fin that does not function in swimming.
Eggs deposited in quadrangular cases with a horn at each
corner. Adults 18 cm to 2.4 m long. The largest group of
batoids, found in all seas including the Arctic and Antarctic,
benthic in habitat and ranging from inshore to very deep
water. Two to 4 or more families depending on the classification used; at least 15 or 16 genera, with 200-210 species.
Skates
Family No. 25: RAJIDAE
by PA Hulley
Roe
Disc quadrangular to rhomboidal; snout long and acutely
angled to short and obtusely rounded; tail with lateral folds,
2 dorsal fins and caudal fin. Mouth transverse to arched,
with numerous teeth, set in bands along jaws in quincunx to
parallel pattern; teeth exhibiting sexual dimorphism in
many species. Five pairs of ventral gill slits. Anterior margin of neurocranium produced medially as a rostral bar,
ranging from a stout conical rod to a delicate slender bar, or
rostrum absent; pectorals with radials of ordinary form,
without lateral processes; propterygia falling well short of,
or in contact with, tip of rostrum. Pelvic girdle transverse,
Sandkruipers & Roe
with weakly to strongly developed lateral prepelvic and iliac
processes. Clasper with 3-9 terminal cartilages.
Benthic in all oceans, from Arctic to Antarctic waters and
from shallow coastal shelf to abyssal regions; rare in tropical
shallow waters, especially in vicinity of coral reefs; some
species found in brackish waters. Feed on other benthic
organisms. Oviparous. Skate wings are good eating. Hulley
(1970, 1972a, 1972b, 1977) has revised the southern African
species. Nine genera with more than 200 species; 4 genera in
our area. Snout length is measured from tip of snout to a
line joining front of orbits.
KEY TO GENERA
1a V with an anterior limb-like structure completely
separate externally from posterior part offin; lateral
margin of V confluent with rear edge of disc ......... Cruriraja
1b Anterior lobe of V joined to rest of fin; lateral edge of
V not joined to edge of disc . . . . . . . . . . . . . . . . . . . . . . . . . 2
2a Propterygia of P falling distinctly short of tip of snout,
separated from rostrum by a semi-cartilaginous space;
rostral cartilage extending to tip of snout, rigid and
stout, although somewhat tapering anteriorly; rostral
appendices dorsoventrally flattened, short or long,
but always fused to rostral bar throughout their
length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Raja
2b Propterygia extending almost to tip of snout; rostral
cartilage extending to tip of snout, or over two thirds
of this distance, as delicate, flexible rod; rostral
appendices elongate, separated from rostral bar over
most of theirlength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3a Rostral base broad, with rostral bar gently tapering,
reaching tip of snout; anterior fontanelle broad and
pear-shaped; preorbital processes well developed;
(less than 30 rows of teeth in upper jaw; distance
from middle of vent to 1st D origin 1.3-1.6 in
distance from tip of snout to middle of vent) ........ Bathyraja
3b Rostral base narrow, with rostral bar markedly
tapering, failing to reach rostral node; anterior
fontanelle narrow and shaped like isosceles triangle;
preorbital processes poorly developed; (more than
30 rows of teeth in upper jaw; distance from middle
of vent to 1st D origin 1.3-1.7 times distance from
tip of snout to middle of vent) ................... Neoraja
Genus Bathyraja Ishiyama, 1968
Pectorals with propterygia extending to tip of rostral
cartilage; rostrum slender and unsegmented, rostral appendices short, with free posterior margins. Pelvic girdle transverse; prepelvic processes varying in length; iliac processes
recurved; 2 or more obturatorial foramina.
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Guitarfishes & Skates
Thick-bodied or greatly flattened batoids with pectoral
fins variably expanded and fused with head and trunk.
Snout usually angular, sometimes broadly rounded. Nasal
flaps not fused to each other across the snout in our species.
No electric organs, or a slender pair in tail. Usually 2 dorsal
fins, one or none in a few genera; tail thick or relatively
slender, without a sting; caudal fin large or variably reduced.
Oviparous or ovoviviparous. The largest group of batoids,
with 3 to 7 families according to the classification used.
Suborder RAJOIDEI
Skates
Roe
Flattened batoids with pectoral fins greatly expanded and
fused with head and trunk to form a disc. Nostrils close to
mouth, with nasal flaps expanded posteriorly to overlap
mouth. A pair of small slender electric organs usually
present in tail. Pelvic fins with anterior ends expanded as
distinct lobes, these sometimes entirely separate from posterior lobes. Usually 2 small dorsal fins (sometimes absent)
close to tail tip; tail slender but not whip-like, with a
reduced caudal fin that does not function in swimming.
Eggs deposited in quadrangular cases with a horn at each
corner. Adults 18 cm to 2.4 m long. The largest group of
batoids, found in all seas including the Arctic and Antarctic,
benthic in habitat and ranging from inshore to very deep
water. Two to 4 or more families depending on the classification used; at least 15 or 16 genera, with 200-210 species.
Skates
Family No. 25: RAJIDAE
by PA Hulley
Roe
Disc quadrangular to rhomboidal; snout long and acutely
angled to short and obtusely rounded; tail with lateral folds,
2 dorsal fins and caudal fin. Mouth transverse to arched,
with numerous teeth, set in bands along jaws in quincunx to
parallel pattern; teeth exhibiting sexual dimorphism in
many species. Five pairs of ventral gill slits. Anterior margin of neurocranium produced medially as a rostral bar,
ranging from a stout conical rod to a delicate slender bar, or
rostrum absent; pectorals with radials of ordinary form,
without lateral processes; propterygia falling well short of,
or in contact with, tip of rostrum. Pelvic girdle transverse,
Sandkruipers & Roe
with weakly to strongly developed lateral prepelvic and iliac
processes. Clasper with 3-9 terminal cartilages.
Benthic in all oceans, from Arctic to Antarctic waters and
from shallow coastal shelf to abyssal regions; rare in tropical
shallow waters, especially in vicinity of coral reefs; some
species found in brackish waters. Feed on other benthic
organisms. Oviparous. Skate wings are good eating. Hulley
(1970, 1972a, 1972b, 1977) has revised the southern African
species. Nine genera with more than 200 species; 4 genera in
our area. Snout length is measured from tip of snout to a
line joining front of orbits.
KEY TO GENERA
1a V with an anterior limb-like structure completely
separate externally from posterior part offin; lateral
margin of V confluent with rear edge of disc ......... Cruriraja
1b Anterior lobe of V joined to rest of fin; lateral edge of
V not joined to edge of disc . . . . . . . . . . . . . . . . . . . . . . . . . 2
2a Propterygia of P falling distinctly short of tip of snout,
separated from rostrum by a semi-cartilaginous space;
rostral cartilage extending to tip of snout, rigid and
stout, although somewhat tapering anteriorly; rostral
appendices dorsoventrally flattened, short or long,
but always fused to rostral bar throughout their
length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Raja
2b Propterygia extending almost to tip of snout; rostral
cartilage extending to tip of snout, or over two thirds
of this distance, as delicate, flexible rod; rostral
appendices elongate, separated from rostral bar over
most of theirlength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3a Rostral base broad, with rostral bar gently tapering,
reaching tip of snout; anterior fontanelle broad and
pear-shaped; preorbital processes well developed;
(less than 30 rows of teeth in upper jaw; distance
from middle of vent to 1st D origin 1.3-1.6 in
distance from tip of snout to middle of vent) ........ Bathyraja
3b Rostral base narrow, with rostral bar markedly
tapering, failing to reach rostral node; anterior
fontanelle narrow and shaped like isosceles triangle;
preorbital processes poorly developed; (more than
30 rows of teeth in upper jaw; distance from middle
of vent to 1st D origin 1.3-1.7 times distance from
tip of snout to middle of vent) ................... Neoraja
Genus Bathyraja Ishiyama, 1968
Pectorals with propterygia extending to tip of rostral
cartilage; rostrum slender and unsegmented, rostral appendices short, with free posterior margins. Pelvic girdle transverse; prepelvic processes varying in length; iliac processes
recurved; 2 or more obturatorial foramina.
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