263: BALISTIDAE (TRIGGERFISHES)
south to Durban, once to Port Alfred. Found on upper
part of outer slope of seaward reef below reef edge; feeds
on sponges (Klausewitz, 1974) and zooplankton (Randall,
1983).
263.10 Odonus niger: 35 cm (Seychelles).
Genus Pseudoba/istes Bleeker, 1866
Mouth terminal; teeth uneven, notched; enlarged bony
plates behind gill slit; groove before eye under nostrils;
scales behind naked cheek area smaller than body scales.
Three species, 2 in our area; P. naufragium Jordan &
Starks, 1895 is restricted to the eastern Pacific.
KEY TO SPECIES
1a No spines on C peduncle; soft 0 & A elevated in front .... P. Juseus
1 b C peduncle with.5 or 6 longitudinal rows of small
spines; soft 0 & A rounded. not elevated in
front ........................................................ P. Jlavimarginatus
263.11 Pseudobalistes flavimarginatus
(Ruppell,1829)
PLATE 136
Yellowface triggerfish
Geelkop-snellervis
Batistes Jlavimarginatus Riippell, 1829: 33 (Red Sea). Psuedobalistes
Jlavomarginatus (sic) : Smith , SFSA No. 1167*; Matsuura, 1980: 36*
o III+24-26; A 22-24; P 15 ; LS 28-33 ; shallow horizontal grooves on
upper cheek; C rounded in young to emarginate or double emarginate
with lobes produced in adult.
Attains 60 cm. Red Sea and tropical Indo-Pacific south to
Natal. Found on lagoon slope and lagoon floor (Klausewitz,
1974).
263.12 Pseudobalistes fuscus
(Bloch & Schneider, 1801)
PLATES 137 & 139
Rippled triggerfish
Gerimpelde snellervis
Balistes JlIsells Bloch & Schneider, 1801: 471 (on Lacepecte; no locality).
PselldobalistesJuscus: Smith, SFSA No. 1168*; Matsuura , 1980: 37*.
DIll +24-27; A 21-24 ; P 14-15 ; LS 35-46; shallow horizontal grooves on
lower cheek; C rounded in young, lobes produced with growth.
880
Dark brown, each scale with yellow spot; P, soft D, A and
C dark with wide yellow margins. Juveniles yellowish
brown covered with bluish grey spots and blotches. Attains
55 cm. Red Sea and Indo-West Pacific, south to Durban.
Genus Rhinecanthus Swainson, 1839
Mouth terminal; teeth unequal, notched; enlarged bony
scales behind gill slit; no groove before eye; 3rd D spine
very small; C peduncle with 3-5 rows of small spines. Six
species (Randall & Steene, 1983); 2 species in our area. R.
verrucosus (Linnaeus, 1758), an Indo-WestPacific species
reported from Chagos Ids. and Mauritius but not yet found
in our area, has a large elliptical black blotch on ventral part
of body not reaching P or upper body. R. cinereus (Bonnaterre, 1788), known from Mauritius, Reunion, Madagascar and the Comores, has a black band from eye to P base, C
mostly yellow with white rear margin and black peduncle.
KEY TO SPECIES
1 a Four or 5 longitudinal rows of antrorse spines on
C peduncle ..................................................... R. reetangulus
1 b Three longitudinal rows of small antrorse spines
on C peduncle, upper 2 longer than lowest ................ R. aeuleatus
263.13 Rhinecanthus aculeatus
(Linnaeus, 1758)
PLATE 137
Blackbar triggerfish
Swartbalk -snellervis
Balistes aeuleatus Linnaeus, 1758: 328 (India). Rhineeanthus aeuleatus:
Smith, SFSA No. 1169*; Sanches, 1963: 177*; Matsuura , 1980: 56*.
o III+23-26; A 21-22; P 12-14; LS 32-39; lowest longitudinal row of tail
spines restricted to C peduncle.
Attains 30 cm. Common in tropical Indo-West Pacific,
south to Algoa Bay. Sleeps on its side at night and makes a
whirring noise when startled. Found in quiet waters of
lagoon sandy areas and parts of seaward reef (Klausewitz,
1974).
263.14 Rhinecanthus rectangulus
(Bloch & Schneider, 1801)
PLATE 137
Patchy triggerfish
Gelapte snellervis
Balistes reetangulus Bloch & Schneider, 1801: 465 (Indian Ocean).
Rhineeanthus reetangulus: Smith, SFSA No. 1170*; Tyler, 1980: 126* .
Rhinecanthus eeharpe: Matsuura, 1980: 55*.
DIll +22-24; A 20-21; P 13-15; LS 33-39; C rounded; lobes only slightly
produced in adults. The species name "echarpe" used by Lacepede is not
valid as it is a French vernacular name.
Body orange-brown above; head and belly white; soft D,
A and P pale, C dusky. Attains 20-30 cm. Tropical IndoWest Pacific, south to East London . Found on outer reef
and outer sand zone (Klausewitz, 1974).
south to Durban, once to Port Alfred. Found on upper
part of outer slope of seaward reef below reef edge; feeds
on sponges (Klausewitz, 1974) and zooplankton (Randall,
1983).
263.10 Odonus niger: 35 cm (Seychelles).
Genus Pseudoba/istes Bleeker, 1866
Mouth terminal; teeth uneven, notched; enlarged bony
plates behind gill slit; groove before eye under nostrils;
scales behind naked cheek area smaller than body scales.
Three species, 2 in our area; P. naufragium Jordan &
Starks, 1895 is restricted to the eastern Pacific.
KEY TO SPECIES
1a No spines on C peduncle; soft 0 & A elevated in front .... P. Juseus
1 b C peduncle with.5 or 6 longitudinal rows of small
spines; soft 0 & A rounded. not elevated in
front ........................................................ P. Jlavimarginatus
263.11 Pseudobalistes flavimarginatus
(Ruppell,1829)
PLATE 136
Yellowface triggerfish
Geelkop-snellervis
Batistes Jlavimarginatus Riippell, 1829: 33 (Red Sea). Psuedobalistes
Jlavomarginatus (sic) : Smith , SFSA No. 1167*; Matsuura, 1980: 36*
o III+24-26; A 22-24; P 15 ; LS 28-33 ; shallow horizontal grooves on
upper cheek; C rounded in young to emarginate or double emarginate
with lobes produced in adult.
Attains 60 cm. Red Sea and tropical Indo-Pacific south to
Natal. Found on lagoon slope and lagoon floor (Klausewitz,
1974).
263.12 Pseudobalistes fuscus
(Bloch & Schneider, 1801)
PLATES 137 & 139
Rippled triggerfish
Gerimpelde snellervis
Balistes JlIsells Bloch & Schneider, 1801: 471 (on Lacepecte; no locality).
PselldobalistesJuscus: Smith, SFSA No. 1168*; Matsuura , 1980: 37*.
DIll +24-27; A 21-24 ; P 14-15 ; LS 35-46; shallow horizontal grooves on
lower cheek; C rounded in young, lobes produced with growth.
880
Dark brown, each scale with yellow spot; P, soft D, A and
C dark with wide yellow margins. Juveniles yellowish
brown covered with bluish grey spots and blotches. Attains
55 cm. Red Sea and Indo-West Pacific, south to Durban.
Genus Rhinecanthus Swainson, 1839
Mouth terminal; teeth unequal, notched; enlarged bony
scales behind gill slit; no groove before eye; 3rd D spine
very small; C peduncle with 3-5 rows of small spines. Six
species (Randall & Steene, 1983); 2 species in our area. R.
verrucosus (Linnaeus, 1758), an Indo-WestPacific species
reported from Chagos Ids. and Mauritius but not yet found
in our area, has a large elliptical black blotch on ventral part
of body not reaching P or upper body. R. cinereus (Bonnaterre, 1788), known from Mauritius, Reunion, Madagascar and the Comores, has a black band from eye to P base, C
mostly yellow with white rear margin and black peduncle.
KEY TO SPECIES
1 a Four or 5 longitudinal rows of antrorse spines on
C peduncle ..................................................... R. reetangulus
1 b Three longitudinal rows of small antrorse spines
on C peduncle, upper 2 longer than lowest ................ R. aeuleatus
263.13 Rhinecanthus aculeatus
(Linnaeus, 1758)
PLATE 137
Blackbar triggerfish
Swartbalk -snellervis
Balistes aeuleatus Linnaeus, 1758: 328 (India). Rhineeanthus aeuleatus:
Smith, SFSA No. 1169*; Sanches, 1963: 177*; Matsuura , 1980: 56*.
o III+23-26; A 21-22; P 12-14; LS 32-39; lowest longitudinal row of tail
spines restricted to C peduncle.
Attains 30 cm. Common in tropical Indo-West Pacific,
south to Algoa Bay. Sleeps on its side at night and makes a
whirring noise when startled. Found in quiet waters of
lagoon sandy areas and parts of seaward reef (Klausewitz,
1974).
263.14 Rhinecanthus rectangulus
(Bloch & Schneider, 1801)
PLATE 137
Patchy triggerfish
Gelapte snellervis
Balistes reetangulus Bloch & Schneider, 1801: 465 (Indian Ocean).
Rhineeanthus reetangulus: Smith, SFSA No. 1170*; Tyler, 1980: 126* .
Rhinecanthus eeharpe: Matsuura, 1980: 55*.
DIll +22-24; A 20-21; P 13-15; LS 33-39; C rounded; lobes only slightly
produced in adults. The species name "echarpe" used by Lacepede is not
valid as it is a French vernacular name.
Body orange-brown above; head and belly white; soft D,
A and P pale, C dusky. Attains 20-30 cm. Tropical IndoWest Pacific, south to East London . Found on outer reef
and outer sand zone (Klausewitz, 1974).