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the web of life in southern Africa

Rajidae (hardnose skates)

Life > Eukaryotes > Opisthokonta > Metazoa (animals) > Bilateria > Deuterostomia > Chordata > Craniata > Vertebrata (vertebrates)  > Gnathostomata (jawed vertebrates) > Chondrichthyes > Elasmobranchii > Batoidei > 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.

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

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.

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

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

Leucoraja compagnoi (Tigertail skate)

 

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

Malacoraja sp. (Natal soft skate)

 

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.

Okamejei heemstrai (Narrow skate)

 

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.

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.

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.

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

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.

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.

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.

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.

Text by Leonard J.V. Compagno, David A. Ebert and Malcolm J. Smale