Family No. 15: CETORHINIDAE
by A.J. Bass
Basking sharks
Koesterhaaie
Large, filter-feeding sharks with a definite snout and long
gill-rakers. Eyes in front of mouth corners. Teeth minute,
numerous. First gill slits almost meeting ventrally; last gill
slits in front of and extending below pectoral origins. Precaudal vertebrae 50-53. A single genus, Cetorhinus Blainville, 1816, with 1 widespread species.
Basking shark
16: ALOPIIDAE (THRESHER SHARKS)
15.1 Cetorhinus maximus
(Gunnerus, 1765)
PLATE 2
Koesterhaai
Squalus maximus Gunnerus, 1765: 33, PI. 2 (Norway). Halsydrus
maximus: Smith, SFSA No. 23*. Cetorhinus maximus: Bass et aI., 1975:
31*; Compagno, 1981*.
Dark grey above, paler below, sometimes with paler
bands or patches. Mature at 4-5 m; attains 9 m, perhaps
over 10 m. Probably ovoviviparous. Plankton feeder.
Normally docile but may attack boats if provoked. A few
records from the southwestern Cape; occurs in temperate
wllter~ of llll Oc.elln~
15.1 Cetorhinus maximus: 808 cm mature female (NW Atlantic; after Bigelow & Schroeder, 1948).
Family No. 16: ALOPIIDAE
by A.J. Bass
Thresher sharks
Sambokhaaie
Caudal fin long, about half total length. Minute second
dorsal and anal fins. Nostrils separate from mouth. Distinct
upper precaudal pit. Relatively large, attaining 3-5 m. Grey
dorsally, white below. Feed on small fish and squid, possibly herding prey into a small area by means of the long tail.
Mainly oceanic but regularly caught inshore; often foul
hooked in tail fin. Ovoviviparous; the embryos are oviphagous. A single genus, Alopias Rafinesque, 1810, with 3
species, all found in our area.
N
16.1 A/opias pe/agicus: 277 cm immature female (Durban). N, T & d as in 2.1.
KEY TO SPECIES
1a Eyes large, extending onto dorsal surface of head;
less than 15 teeth on each side of jaws; hind tip of
1st D over or slightly in front of V origin ............. A. superci/iosus
1b Eyes small, not visible on top of head; more than 15 teeth
on each side of jaws; hind tip of 1st D well in front of V origin ..... 2
2a Teeth markedly oblique with one or more basal
denticIes on outer side .......................................... A. pelagicus
2b Teeth erect or slightly oblique without any basal
denticIes on outer side ........................................... A. vulpinus
:(
101
by A.J. Bass
Basking sharks
Koesterhaaie
Large, filter-feeding sharks with a definite snout and long
gill-rakers. Eyes in front of mouth corners. Teeth minute,
numerous. First gill slits almost meeting ventrally; last gill
slits in front of and extending below pectoral origins. Precaudal vertebrae 50-53. A single genus, Cetorhinus Blainville, 1816, with 1 widespread species.
Basking shark
16: ALOPIIDAE (THRESHER SHARKS)
15.1 Cetorhinus maximus
(Gunnerus, 1765)
PLATE 2
Koesterhaai
Squalus maximus Gunnerus, 1765: 33, PI. 2 (Norway). Halsydrus
maximus: Smith, SFSA No. 23*. Cetorhinus maximus: Bass et aI., 1975:
31*; Compagno, 1981*.
Dark grey above, paler below, sometimes with paler
bands or patches. Mature at 4-5 m; attains 9 m, perhaps
over 10 m. Probably ovoviviparous. Plankton feeder.
Normally docile but may attack boats if provoked. A few
records from the southwestern Cape; occurs in temperate
wllter~ of llll Oc.elln~
15.1 Cetorhinus maximus: 808 cm mature female (NW Atlantic; after Bigelow & Schroeder, 1948).
Family No. 16: ALOPIIDAE
by A.J. Bass
Thresher sharks
Sambokhaaie
Caudal fin long, about half total length. Minute second
dorsal and anal fins. Nostrils separate from mouth. Distinct
upper precaudal pit. Relatively large, attaining 3-5 m. Grey
dorsally, white below. Feed on small fish and squid, possibly herding prey into a small area by means of the long tail.
Mainly oceanic but regularly caught inshore; often foul
hooked in tail fin. Ovoviviparous; the embryos are oviphagous. A single genus, Alopias Rafinesque, 1810, with 3
species, all found in our area.
N
16.1 A/opias pe/agicus: 277 cm immature female (Durban). N, T & d as in 2.1.
KEY TO SPECIES
1a Eyes large, extending onto dorsal surface of head;
less than 15 teeth on each side of jaws; hind tip of
1st D over or slightly in front of V origin ............. A. superci/iosus
1b Eyes small, not visible on top of head; more than 15 teeth
on each side of jaws; hind tip of 1st D well in front of V origin ..... 2
2a Teeth markedly oblique with one or more basal
denticIes on outer side .......................................... A. pelagicus
2b Teeth erect or slightly oblique without any basal
denticIes on outer side ........................................... A. vulpinus
:(
101