Rajidae (hardnose skates)
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Rajoidei
Bottom-dwelling rays with broad pectoral fins
forming a prominent disk with the body, head and snout, a slender to
stout tail with a tiny caudal fin and usually two small dorsal fins
near its tip, and usually enlarged scales or thorns along the back,
tail, and elsewhere on the body. Adult males have enlarged, hooked,
movable alar spines in rows on upper surface of disk near outer
corners, apparently used in courtship and during copulation. Skates
lay eggs encased in dark, pillow-shaped cases with horns at each
corner (`mermaid's purses') on the bottom, which hatch in a few
months to over a year. 222 species worldwide, with 25 in the area.
Species found in Southern Africa
Amblyraja
radiata (Thorny skate) An extremely rough skate with a stiff, bluntly
triangular snout, tail shorter than body, and upper disk covered by
close-set large thorns with star-shaped bases. Colour grey-brown
above, with a few small black spots, front lobes of pelvics with
black blotches; underside of disk white with dark spots and blotches
on tail and pelvic fins. |
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Amblyraja robertsi (Bigmouth skate)
A large dark
deepwater skate with a stiff, bluntly triangular snout,
huge mouth almost equal to snout length, tail shorter
than body, and smooth disk except for large star-based
thorns around eyes, on shoulders, and along midline of
back and tail. Colour dark grey above and below, white
blotches on underside |
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Dipturus campbelli (Blackspot skate)
A black-spotted
longnosed skate with an elongated acutely triangular
snout, disk with rounded corners, tail stout, slightly
shorter than body, and slightly swollen along its
midlength, small thorns on nape and on midback to 1st
dorsal fin, and underside of disk without small
denticles except on snout tip and edges. Colour medium
grey or brownish above, grey below with many small black
spots on upper surface, conspicuous black pores on lower
surface. |
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Dipturus doutrei (Javelin skate)
An all-dark longnose
skate with an acutely triangular, elongated snout, disk
with narrowly rounded outer corners, a stout tail
shorter than the body and with its midsection swollen
and sausage-shaped, no thorns on nape and along back,
and underside of disk largely smooth except for small
denticles on snout. Colour dark brown above, with
scattered irregular dark blotches, blackish on rear end
of disk and pelvic fins, underside dark brown with
scattered lighter blotches on disk, at base of pelvic
fins, around vent, and on tail, and black pores |
 |
Dipturus
lanceorostrata (Rattail skate)
A grey, light-spotted
longnosed skate with an acutely triangular, elongated
snout, disk with angular corners, a very slender tail as
long as body that tapers from base to tip, a small spine
at nape, and underside of disk smooth except for small
denticles on snout tip and edges. Colour dark grey above
with many small light spots, thorns conspicuously
lighter than disk; grey below with lighter areas around
gills and at front edge of disk, and black pores |
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Dipturus
pullopunctata (Graybelly or slime skate)
A strikingly
two-toned longnosed skate, warm brown above and abruptly
dark grey below, with a conspicuous large dark brown
blotch on the upper base of each pectoral fin. Snout
moderately elongated and bluntly triangular, pectoral
disk with broadly rounded corners, and tail stout, not
conspicuously swollen, and about equal to body length.
Thorns present at nape and along midline of back and
tail to first dorsal fin, nape spine enormous in young;
underside of disk not covered with small denticles.
Conspicuous wide-spaced black spots on upper disk of
hatchlings and juveniles, inconspicuous or lost on
adolescents and adults, numerous small white spots
sometimes present in adults; undersurface with numerous
black-pigmented pores. |
 |
Dipturus springeri (Roughbelly skate)
An all-dark longnose
skate with the undersurface uniformly roughened by small
denticles, a greatly elongated acutely pointed snout, an
angular pectoral disk that is broader than in other
longnose skates in the area, no nape thorn, and a
moderately stout tail that is not conspicuously swollen.
Colour uniform dark grey to blackish above and below
with black pores on underside. |
 |
Dipturus
stenorhynchus (Prownose skate)
An all-dark longnosed
skate with a broadly triangular, greatly elongated
snout, disk with angular corners, a stout tail shorter
than the body and with its midsection swollen and
sausage-shaped, a small thorn at nape, and underside of
disk smooth. Colour uniform dark grey above and below,
with black pores |
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Leucoraja compagnoi (Tigertail skate) |
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Leucoraja wallacei (Yellowspotted skate)
A narrow-disked skate
with bright yellow spots often in rosettes and whorls,
sometimes forming eye-like markings on pectoral bases.
Snout short, broad and blunt, disk corners broadly
rounded, tail longer than body, disk very rough, with 2
to 4 rows of thorns from midback to 1st dorsal fin. Some
individuals are grey-brown above, with white spots |
 |
Malacoraja
spinacidermis (Roughskin skate)
A deepwater skate
with a very broad, almost pentagonal disk that is light
above, abruptly dark below. Snout bluntly pointed, with
a flexible tip, eyes small and close together, and
pectoral disk with broadly rounded rear margins and
bluntly rounded tips. Small juveniles have large thorns
on shoulders, nape, and tail, but large juveniles and
adults lose all their thorns and are covered only with
small denticles. Colour slate-grey or grey-brown above,
except rear margins of pectoral fins, pelvic fins, and
claspers of adult males which are dark brown, dark brown
below, sometimes with light blotches |
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Malacoraja sp. (Natal soft skate) |
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Neoraja stehmanni (African pygmy skate)
A dwarf softnose
skate with a bluntly pointed snout, very large close-set
eyes, angular pectoral disk with rounded corners, tail
longer than body in adults, large thorns around eyes, on
shoulders, and in an interrupted single row from back to
dorsal fins. Pectoral disk of adult males with anterior
edges more undulated than females. Colour brownish grey
above, with 6-7 cross bars on tail, underside pale with
dark brown areas along the front and rear edges of the
disk, on snout, and on underside of tail. |
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Okamejei heemstrai (Narrow skate) |
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Raja
miraletus (Twineyed skate)
A small brown skate
with two bright blue-centered ocelli or eyespots on the
pectoral bases, a short bluntly pointed snout, and
angular pectoral disk. Colour medium-brown above, often
with small close-set dark brown spots, white below and
without dark pores. |
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Raja
straeleni (Biscuit skate)
A
brown, black-spotted skate with a blunt, angular snout,
broad angular disk, long stout tail, strong thorns on
upper surface of disk and tail at all stages, sometimes
on underside in large individuals. Colour medium brown
or grey-brown, usually with small to large black spots,
whorls, and blotches; many individuals with a gold and
black, transversely oblong eyespot on each pectoral
base. Underside of disk white, no dark pores. |
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Rajella barnardi (Bigthorn skate) A grey skate with a short, obtusely pointed
shout, large eyes, a thick disk, tail about as long as body, and
conspicuous large white thorns on upper surface including snout.
Colour light grey above, grey or white below, with darker patches on
rear of disk and underside of tail. |
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Rajella caudaspinosa (Munchkin skate)
A small grey skate
with very large, close-set bulging eyes, a very short,
obtusely pointed snout, thick disk, thick tail that is
much longer than body, and conspicuous light thorns that
make disk and tail extremely rough. Colour light grey to
brownish above, with or without darker spots, young with
distinctive white-barred pattern, white below |
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Rajella dissimilis (Ghost skate)
A grey skate with a
moderately long snout, small eyes, flat disk, tail about
as long as body, moderately large inconspicuous light
thorns on upper surface, with a few on snout, and
middorsal line of thorns reduced in adults and subadults.
Colour whitish-grey to dark grey above, white below,
with dark rear margins and dark patches on underside of
tail. |
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Rajella leopardus (Leopard skate)
A large grey skate
with a moderately long snout, small eyes, flat disk,
tail about as long as body, inconspicuous small light
thorns on upper surface including snout, middorsal line
of thorns not reduced. Colour medium grey to brownish
above, often with blackish spots, white below or white
mottled with dusky patches. |
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Rajella ravidula (Smoothback skate)
A long-nosed grey skate with small eyes, a thick disk,
tail about as long as body, conspicuous moderate-sized
light thorns in two prominent rows from shoulders to 1st
dorsal fin, middorsal thorns absent or very few, thorns
absent from snout. Colour medium grey to purplish-brown
above, white below but dusky on disk margins, around
vent, and on underside of tail. |
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Rostroraja alba (Spearnose skate)
A giant skate with a
broad-based, abruptly narrow-tipped snout covered with
small sharp thorns, angular pectoral disk, no large
thorns on nape and back, three rows of large thorns on
tail. Hatchling young are plain reddish-brown above,
often with blue spots, and white below with broad dusky
grey margins on the disk; larger immatures and adults
are grey above with numerous small white spots, white
below. Underside without black pores. |
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Text by Leonard J.V. Compagno, David A. Ebert
and Malcolm J. Smale
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