rear part of body with slight mid-longitudinal ridge; pelvic
terminus movable. Transformation from prejuvenile occurs
at 9-14 cm SL. Revised by Randall and Klausewitz (1973); 3
species, all in our area.
KEY TO SPECIES
la Soft D & A pale with prominent black edging
(juveniles have black longitudinal lines on fins);
C pale with narrow black line distally on upper
and lower margins ................................................... M. vidua
Ib Soft D & A black with white line along base; C mostly black ....... 2
2a C emarginate to lunate, upper and lower lobes
produced (except in juveniles); scale rows from
corner of mouth to lower end of gill slit 20-25 ................. M. niger
2b C slightly rounded to slightly emarginate; scale
rows from corner of mouth to lower end of gill slit
27-31 .................................................................. M. indicus
263.7 Melichthys indicus
Randall & Klausewitz, 1973
Indian triggerfish
Indiese snellervis
Melichthys ringens (non Osbeck): Smith, SFSA No. 1159*. Metichthys
indicus Randall & Klausewitz, 1973: 64, Figs. 4-6 (Thailand); Smith, 1980:
186 (not No. 1158).
DIll + 30-35; A 27-30; P 14-16; LS 60-70; head scales 24-31; a very shallow oblique groove on cheek; ridges along hind scales less developed than
those in M. niger.
Narrow white margin round C; shallow groove on cheek
sometimes bluish or violet in life. Attains about 25 cm.
Tropical Indian Ocean, south to Sodwana Bay.
263.7 Melichthys indicus: 22 em (Kenya).
263.8 Melichthys niger
(Bloch,1786)
Black triggerfish
Swart snellervis
Balistes niger Bloch, 1786: 27, PI. 152, Fig. 2 (incorrectly labelled
Batistes ringens; China Sea). Melichthys niger: Randall & Klausewitz,
1973: 60*; Smith, 1975: 82; Tyler, 1980: 121*.
D III+32-35; A 28-31; P 15-17; LS 57-66; head scales 20-25; longitudinal ridges along C peduncle scales prominent.
263: BALISTIDAE (TRIGGERFISHES)
In life: submarginal blue line on C bends into lobes, blue
line along base of soft D and A, and blue lines radiate from
eye. Blue disappears with death, leaving black fish with
white line along base of soft D and A. Attains at least 35 cm.
Circumtropical, has been found at Durban. Klausewitz
(1974) noted that M. niger is found on upper reef edge of
outer slope of seaward reef, predominantly eating calcerous
algae; also feeds on zooplankton.
263.8 Me/ichthys niger: 23 em (N. Mozambique).
263.9 Melichthys vidua
(Solander, 1844)
PLATE 139
Pinktail triggerfish
Pienkstert -snellervis
Batistes vidua Solander, in Richardson, 1844: 128, PI. 59, Figs. 9, 10
(Tahiti). Melichthys vidua: Smith, SFSA No. 1158*; Randall & Klausewitz, 1973: 62*.
D III+32-35; A 28-31; P 14-16; LS 62-74; head scale rows 28-32; C
slightly emarginate, double emarginate or truncate; ridges formed by
spinules on hind body scales not prominent.
Juveniles lighter with longitudinal dark lines on A and
soft D, and dark lines radiating from eye. Attains nearly 40
cm. Tropical IndO-Pacific, south to Durban; rare.
Genus Odonus Gistel, 1848
Easily recognised by the jutting lower jaw, the bluish
black body and red fangs. Monotypic.
263.10 Odonus niger
(RUppell, 1836)
Redfang triggerfish
Rooitand-snellervis
Xenodon (Balistes) niger Riippell, 1836: 53, PI. 14, Fig. 3 (Red Sea).
Odonus niger: Smith, SFSA No. 1155*; Tyler, 1980: 101*, 118*, 121 *;
Matsuura, 1980: 34*.
D III+33-36; A 28-30; P 14-15; LS 29-34; head scale rows 19-23; enlarged bony scales behind gill slit; deep groove before eye below nostrils;
C lunate, the lobes greatly produced.
Attains 50 cm. Widespread in tropical Indo-West Pacific
879
terminus movable. Transformation from prejuvenile occurs
at 9-14 cm SL. Revised by Randall and Klausewitz (1973); 3
species, all in our area.
KEY TO SPECIES
la Soft D & A pale with prominent black edging
(juveniles have black longitudinal lines on fins);
C pale with narrow black line distally on upper
and lower margins ................................................... M. vidua
Ib Soft D & A black with white line along base; C mostly black ....... 2
2a C emarginate to lunate, upper and lower lobes
produced (except in juveniles); scale rows from
corner of mouth to lower end of gill slit 20-25 ................. M. niger
2b C slightly rounded to slightly emarginate; scale
rows from corner of mouth to lower end of gill slit
27-31 .................................................................. M. indicus
263.7 Melichthys indicus
Randall & Klausewitz, 1973
Indian triggerfish
Indiese snellervis
Melichthys ringens (non Osbeck): Smith, SFSA No. 1159*. Metichthys
indicus Randall & Klausewitz, 1973: 64, Figs. 4-6 (Thailand); Smith, 1980:
186 (not No. 1158).
DIll + 30-35; A 27-30; P 14-16; LS 60-70; head scales 24-31; a very shallow oblique groove on cheek; ridges along hind scales less developed than
those in M. niger.
Narrow white margin round C; shallow groove on cheek
sometimes bluish or violet in life. Attains about 25 cm.
Tropical Indian Ocean, south to Sodwana Bay.
263.7 Melichthys indicus: 22 em (Kenya).
263.8 Melichthys niger
(Bloch,1786)
Black triggerfish
Swart snellervis
Balistes niger Bloch, 1786: 27, PI. 152, Fig. 2 (incorrectly labelled
Batistes ringens; China Sea). Melichthys niger: Randall & Klausewitz,
1973: 60*; Smith, 1975: 82; Tyler, 1980: 121*.
D III+32-35; A 28-31; P 15-17; LS 57-66; head scales 20-25; longitudinal ridges along C peduncle scales prominent.
263: BALISTIDAE (TRIGGERFISHES)
In life: submarginal blue line on C bends into lobes, blue
line along base of soft D and A, and blue lines radiate from
eye. Blue disappears with death, leaving black fish with
white line along base of soft D and A. Attains at least 35 cm.
Circumtropical, has been found at Durban. Klausewitz
(1974) noted that M. niger is found on upper reef edge of
outer slope of seaward reef, predominantly eating calcerous
algae; also feeds on zooplankton.
263.8 Me/ichthys niger: 23 em (N. Mozambique).
263.9 Melichthys vidua
(Solander, 1844)
PLATE 139
Pinktail triggerfish
Pienkstert -snellervis
Batistes vidua Solander, in Richardson, 1844: 128, PI. 59, Figs. 9, 10
(Tahiti). Melichthys vidua: Smith, SFSA No. 1158*; Randall & Klausewitz, 1973: 62*.
D III+32-35; A 28-31; P 14-16; LS 62-74; head scale rows 28-32; C
slightly emarginate, double emarginate or truncate; ridges formed by
spinules on hind body scales not prominent.
Juveniles lighter with longitudinal dark lines on A and
soft D, and dark lines radiating from eye. Attains nearly 40
cm. Tropical IndO-Pacific, south to Durban; rare.
Genus Odonus Gistel, 1848
Easily recognised by the jutting lower jaw, the bluish
black body and red fangs. Monotypic.
263.10 Odonus niger
(RUppell, 1836)
Redfang triggerfish
Rooitand-snellervis
Xenodon (Balistes) niger Riippell, 1836: 53, PI. 14, Fig. 3 (Red Sea).
Odonus niger: Smith, SFSA No. 1155*; Tyler, 1980: 101*, 118*, 121 *;
Matsuura, 1980: 34*.
D III+33-36; A 28-30; P 14-15; LS 29-34; head scale rows 19-23; enlarged bony scales behind gill slit; deep groove before eye below nostrils;
C lunate, the lobes greatly produced.
Attains 50 cm. Widespread in tropical Indo-West Pacific
879