Order CARCHARHINIFORMES
Ground sharks
Typical sharks with 2 spineless dorsal fins, an anal fin, 5
pairs of gill slits on sides of head, a movable lower
nictitating eyelid, mouth long and extending behind eyes.
Intestinal valve of conico-spiral or scroll type, like a broad
augur drill or a swiss roll or rolled pancake. Oviparous,
eggs laid in small purse-like egg-cases with tendrils, or livebearing, with or without placental attachment between
young and mother. Adults 15 cm to possibly 7.4 m long;
most species between 30 and 200 cm. The largest group of
living sharks, with inshore, oceanic, and deep-water
benthic species in all temperate to tropical seas, and a few
species that enter freshwater. Five to 8 families, depending
on the classification used; about 48 genera and 200 species.
Family No.9: CARCHARHINIDAE
by A.J. Bass, P.C. Heemstra & L.J.V. Compagno
Requiem sharks
Blouhaaie
Two dorsal fins without spines. First dorsal base much
shorter than upper caudal lobe , its origin well in front of pelvic fins. Anal fin well separated from caudal fin. Caudal fin
with more or less distinct lower lobe, but not lunate, much
less than half of total length. Spiracles small or absent. Nictitans present (rudimentary in Mustelus). Five gill slits, the
last over or behind pectoral fin origin. Nasal barbels absent
(except in Leptocharias); no grooves connecting nostrils
and mouth (except in Scylliogaleus).
The family Carcharhinidae is here used in a broad sense
to include as subfamilies the Triakinae, Leptochariinae and
Hemigaleinae. The family is a diverse assemblage of sharks
ranging in size from the 5.5 metre tiger shark to the diminutive 58 cm bigeye houndshark (Jago omanensis). A few
species are dangerous and known to attack man (e.g., tiger
shark, Zambezi shark), but most carcharhinids are harmless. They occur in temperate and tropical waters of all
oceans and are of considerable economic importance,
either as food or as predators of more valuable crustaceans
and fishes. About 24 genera with about 80 species; there are
36 species that occur or are likely to be found in our area.
KEY TO GENERA
la Precaudal pits (distinct depression in skin of caudal
peduncle at origin of upper and lower C lobes) present ............ 2
1 b Precaudal pits absent ....................................................... 10
Grondhaaie
2a Dermal ridge or keel on each side of caudal peduncle;
long outer lip folds, reaching forward to below eye ..... Galeocerdo
2b No keel on side of caudal peduncle (weak keel present in
Prionace); short outer lip folds, not reaching to below eye ........ 3
3a Second D at least half as high as 1 st D .................................. 4
3b Second D less than half as high as 1st D ................................ 7
4a Lip folds minute, virtually absent; snout short and broadly
rounded, subequal to or less than internostril distance,
half mouth width or less .................................................... 5
4b Lip folds well developed, at least as long as orbit diameter;
snout long and more narrowly rounded, much greater than
internostril distance, half mouth width or more ...................... 6
Sa D and C with white tips; 2nd D about half as high
as 1st D; jaw teeth with side cusps (cusplets) ............ Triaenodon
5b D and C plain; 2nd D about as high as 1st D; teeth without
side cusps .......................................................... Negaprion
6a Upper teeth long, curved, distinctly serrated on
both sides; V notably falcate, their anterior edge
subequal to length of lower C lobe .......................... Hemipristis
6b Upper jaw teeth relatively short, oblique, with several
large lateral serrae (or cusplets), but the inner edge
smooth; V subtriangular, their anterior edge distinctly
less than length oflower C lobe .............................. Paragaleus
7a Second D origin about over A axil; teeth mainly
smooth (large adults of Rhizoprionodon acutus have
weakly serrated teeth with a single oblique cusp) .................... 8
7b Second D origin nearer to a vertical line at A origin than to
vertical at axil; upper jaw teeth serrated (sometimes
minutely) ....................................................................... 9
8a Hind edge of orbit with a distinct notch; combined
length of upper and lower lip folds less than
nostril length ........................................................ Loxodon
8b No notch on rear edge of orbit; length of upper +
lower lip folds equal to or greater than
nostril length ............................................... Rhizoprionodon
9a First D origin about midway between P and V
origins ................................................................ Prionace
9b First D origin closer to P origin than to V origin ...... Carcharhinus
lOa Nostrils with anterior nasal flap in the form of
a slender, pointed barbel; outer lip folds longer than
half mouth width .............................................. Leptocharias
lOb No barbel on front edge of nostrils; outer lip folds
less than half mouth width ................................................ 11
11a Nostrils joined to mouth by a groove; anterior
nasal flaps enormous, joined together to form a "nasal
curtain" that reaches the mouth ........................... Scylliogaleus
11b No groove from nostrils to mouth; anterior nasal
flaps short and well separated from one another .................... 12
12a First D origin in front of P axil; 2nd D axil behind A axil ...... /ago
12b First D origin behind P axil; 2nd D axil in front of A axil ......... 13
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Ground sharks
Typical sharks with 2 spineless dorsal fins, an anal fin, 5
pairs of gill slits on sides of head, a movable lower
nictitating eyelid, mouth long and extending behind eyes.
Intestinal valve of conico-spiral or scroll type, like a broad
augur drill or a swiss roll or rolled pancake. Oviparous,
eggs laid in small purse-like egg-cases with tendrils, or livebearing, with or without placental attachment between
young and mother. Adults 15 cm to possibly 7.4 m long;
most species between 30 and 200 cm. The largest group of
living sharks, with inshore, oceanic, and deep-water
benthic species in all temperate to tropical seas, and a few
species that enter freshwater. Five to 8 families, depending
on the classification used; about 48 genera and 200 species.
Family No.9: CARCHARHINIDAE
by A.J. Bass, P.C. Heemstra & L.J.V. Compagno
Requiem sharks
Blouhaaie
Two dorsal fins without spines. First dorsal base much
shorter than upper caudal lobe , its origin well in front of pelvic fins. Anal fin well separated from caudal fin. Caudal fin
with more or less distinct lower lobe, but not lunate, much
less than half of total length. Spiracles small or absent. Nictitans present (rudimentary in Mustelus). Five gill slits, the
last over or behind pectoral fin origin. Nasal barbels absent
(except in Leptocharias); no grooves connecting nostrils
and mouth (except in Scylliogaleus).
The family Carcharhinidae is here used in a broad sense
to include as subfamilies the Triakinae, Leptochariinae and
Hemigaleinae. The family is a diverse assemblage of sharks
ranging in size from the 5.5 metre tiger shark to the diminutive 58 cm bigeye houndshark (Jago omanensis). A few
species are dangerous and known to attack man (e.g., tiger
shark, Zambezi shark), but most carcharhinids are harmless. They occur in temperate and tropical waters of all
oceans and are of considerable economic importance,
either as food or as predators of more valuable crustaceans
and fishes. About 24 genera with about 80 species; there are
36 species that occur or are likely to be found in our area.
KEY TO GENERA
la Precaudal pits (distinct depression in skin of caudal
peduncle at origin of upper and lower C lobes) present ............ 2
1 b Precaudal pits absent ....................................................... 10
Grondhaaie
2a Dermal ridge or keel on each side of caudal peduncle;
long outer lip folds, reaching forward to below eye ..... Galeocerdo
2b No keel on side of caudal peduncle (weak keel present in
Prionace); short outer lip folds, not reaching to below eye ........ 3
3a Second D at least half as high as 1 st D .................................. 4
3b Second D less than half as high as 1st D ................................ 7
4a Lip folds minute, virtually absent; snout short and broadly
rounded, subequal to or less than internostril distance,
half mouth width or less .................................................... 5
4b Lip folds well developed, at least as long as orbit diameter;
snout long and more narrowly rounded, much greater than
internostril distance, half mouth width or more ...................... 6
Sa D and C with white tips; 2nd D about half as high
as 1st D; jaw teeth with side cusps (cusplets) ............ Triaenodon
5b D and C plain; 2nd D about as high as 1st D; teeth without
side cusps .......................................................... Negaprion
6a Upper teeth long, curved, distinctly serrated on
both sides; V notably falcate, their anterior edge
subequal to length of lower C lobe .......................... Hemipristis
6b Upper jaw teeth relatively short, oblique, with several
large lateral serrae (or cusplets), but the inner edge
smooth; V subtriangular, their anterior edge distinctly
less than length oflower C lobe .............................. Paragaleus
7a Second D origin about over A axil; teeth mainly
smooth (large adults of Rhizoprionodon acutus have
weakly serrated teeth with a single oblique cusp) .................... 8
7b Second D origin nearer to a vertical line at A origin than to
vertical at axil; upper jaw teeth serrated (sometimes
minutely) ....................................................................... 9
8a Hind edge of orbit with a distinct notch; combined
length of upper and lower lip folds less than
nostril length ........................................................ Loxodon
8b No notch on rear edge of orbit; length of upper +
lower lip folds equal to or greater than
nostril length ............................................... Rhizoprionodon
9a First D origin about midway between P and V
origins ................................................................ Prionace
9b First D origin closer to P origin than to V origin ...... Carcharhinus
lOa Nostrils with anterior nasal flap in the form of
a slender, pointed barbel; outer lip folds longer than
half mouth width .............................................. Leptocharias
lOb No barbel on front edge of nostrils; outer lip folds
less than half mouth width ................................................ 11
11a Nostrils joined to mouth by a groove; anterior
nasal flaps enormous, joined together to form a "nasal
curtain" that reaches the mouth ........................... Scylliogaleus
11b No groove from nostrils to mouth; anterior nasal
flaps short and well separated from one another .................... 12
12a First D origin in front of P axil; 2nd D axil behind A axil ...... /ago
12b First D origin behind P axil; 2nd D axil in front of A axil ......... 13
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