243: ACANTHURIDAE (SURGEONFISHES, UNICORNFISHES)
243.5 Acanthurus mata
Cuvier, 1829
PLATES 127 & 130
Elongate surgeon
Lang doktervis
Chaetodon meta Cuvier, 1829: 224 (after Russell, error for mata). Acanthurus mata Valenciennes, in Cuv. & Val., 1835: 202. Acanthurus
lineolalus (non Valenciennes): Smith, SFSA No. 609*_ Acanlhurus bleekeri: Randall, 1956: IS0*.
D IX,24-26; A 111,23-24; P 16-17. Body depth 2.1-2.5 (decreasing with
size), snout 6.6-6.9 in SL; mouth width 4.7-5.0 in head. Up to 24 teeth in
upper jaw and 26 in lower jaw of large adults. C of adults lunate. Dark
brown with lengthwise blue lines on head and body; a yellow area behind
eye and 2 yellow bands extending anteriorly from eye; capable of a colour
change to overall pale bluish.
Attains 50 cm. Indo-Pacific, south to Durban. Appears to
feed mainly if not entirely on zooplankton, More inclined
than most other surgeonfishes to enter turbid water.
243.5 Acanthurus mata: 22.5 cm (Seychelles).
243.6 Acanthurus nigricauda
Duncker & Mohr, 1929
PLATE 129
Epaulette surgeon
Epaulet-doktervis
Acanlhurus gahm nigricauda Duncker & Mohr, 1929 (St. Matthias
Group). Acanthurus nigricans (non Linnaeus): Smith, SFSA No. 612*.
Acanthurus gahhm (non Forsskal): Randall, 1956: 207*.
D IX,25-2S; A 111,23-26; P 17. Body depth 1.9-2.2 in SL (smaller
individuals relatively deeper bodied); caudal spine 4.5-7.5 in head; 16
teeth in both jaws at 74 mm SL, and 19 upper and 22 lower teeth at 226 mm
SL. C of adults strongly lunate, C concavity 3.6 in SL at 237 mm and 6.5 at
76 mm SL. Brown (one colour phase is purplish grey) without lines on
body or spots on head; a horizontal black band passing posteriorly from
upper end of gill opening (band length 4.5-7.0 in SL, first appearing at 6
r
)
243.6 Acanthurus nigricauda: 35 cm (Seychelles). r
814
cm SL); a horizontal black line, progressively narrower anteriorly, extending forward from caudal spine up to half distance to P base (this line
first appearing at a SL of 10 cm); an elongate purple mark may be present
in front of D origin; C brown (often with a white bar across base) with a
whitish posterior margin (fin of young entirely pale); P brown, outer third
pale (inner half of pale zone yellow in life); remaining fins brown.
Attains 40 cm, Indo-Pacific, south to Durban, Not known
from the Red Sea; has been confused with a large Red Sea
endemic species, A. nigricans Linnaeus, 1758 (A, gahhm
Forsskal, 1775 is a synonym) which also has a black band in
the shoulder region, Generally found in protected waters
such as lagoons or bays, around isolated coral heads or
rocks on sandy bottoms,
243.7 Acanthurus nigrofuscus
(Forsskal, 1775)
PLATE 129
Brown surgeon
Bruin doktervis
Chaetodon nigro-fuscus Forsskal, 1775: 64 (Red Sea). Acanthums
nigrofuscus: Randall, 1956: 190*; Winterbottom, 1976: 68; Smith, 1980:
179.
D IX,24-27; A 111,22-24; P 16-17. Body depth 2.0-2.3 in SL; 10 upper
and 12 lower jaw teeth at 55 mm SL, and 14 upper and 16 lower teeth at
148 mm SL; C lunate, concavity 4.5-6.0 in SL. Brown to lavender-brown,
with or without fine bluish grey longitudinal lines on body; lips blackish;
prominent black spot larger than Y;. eye diameter at rear end of D base and
a smaller black spot at end of A base; head and chest with numerous small
orange spots (which mayor may not persist as pale spots in preservative);
a distinct narrow whitish border posteriorly on C; a narrow blackish edge
around caudal spine socket.
A small reef species; attains about 20 cm, Indo-Pacific, to
Coffee Bay, Transkei; common off Natal.
243,7 Acanthurus nigrofuscus: 7 cm (Natal).
243.8 Acanthurus nubi/us
(Fowler & Bean, 1929)
PLATE 129
Bluelined surgeon
Bloulyn-doktervis
Hepallls (Harpurina) nubilus Fowler & Bean, 1929: 253, Fig. I:;
(Celebes). Acanlhurus nuhilus: Randall, 1956: 179*.
243.5 Acanthurus mata
Cuvier, 1829
PLATES 127 & 130
Elongate surgeon
Lang doktervis
Chaetodon meta Cuvier, 1829: 224 (after Russell, error for mata). Acanthurus mata Valenciennes, in Cuv. & Val., 1835: 202. Acanthurus
lineolalus (non Valenciennes): Smith, SFSA No. 609*_ Acanlhurus bleekeri: Randall, 1956: IS0*.
D IX,24-26; A 111,23-24; P 16-17. Body depth 2.1-2.5 (decreasing with
size), snout 6.6-6.9 in SL; mouth width 4.7-5.0 in head. Up to 24 teeth in
upper jaw and 26 in lower jaw of large adults. C of adults lunate. Dark
brown with lengthwise blue lines on head and body; a yellow area behind
eye and 2 yellow bands extending anteriorly from eye; capable of a colour
change to overall pale bluish.
Attains 50 cm. Indo-Pacific, south to Durban. Appears to
feed mainly if not entirely on zooplankton, More inclined
than most other surgeonfishes to enter turbid water.
243.5 Acanthurus mata: 22.5 cm (Seychelles).
243.6 Acanthurus nigricauda
Duncker & Mohr, 1929
PLATE 129
Epaulette surgeon
Epaulet-doktervis
Acanlhurus gahm nigricauda Duncker & Mohr, 1929 (St. Matthias
Group). Acanthurus nigricans (non Linnaeus): Smith, SFSA No. 612*.
Acanthurus gahhm (non Forsskal): Randall, 1956: 207*.
D IX,25-2S; A 111,23-26; P 17. Body depth 1.9-2.2 in SL (smaller
individuals relatively deeper bodied); caudal spine 4.5-7.5 in head; 16
teeth in both jaws at 74 mm SL, and 19 upper and 22 lower teeth at 226 mm
SL. C of adults strongly lunate, C concavity 3.6 in SL at 237 mm and 6.5 at
76 mm SL. Brown (one colour phase is purplish grey) without lines on
body or spots on head; a horizontal black band passing posteriorly from
upper end of gill opening (band length 4.5-7.0 in SL, first appearing at 6
r
)
243.6 Acanthurus nigricauda: 35 cm (Seychelles). r
814
cm SL); a horizontal black line, progressively narrower anteriorly, extending forward from caudal spine up to half distance to P base (this line
first appearing at a SL of 10 cm); an elongate purple mark may be present
in front of D origin; C brown (often with a white bar across base) with a
whitish posterior margin (fin of young entirely pale); P brown, outer third
pale (inner half of pale zone yellow in life); remaining fins brown.
Attains 40 cm, Indo-Pacific, south to Durban, Not known
from the Red Sea; has been confused with a large Red Sea
endemic species, A. nigricans Linnaeus, 1758 (A, gahhm
Forsskal, 1775 is a synonym) which also has a black band in
the shoulder region, Generally found in protected waters
such as lagoons or bays, around isolated coral heads or
rocks on sandy bottoms,
243.7 Acanthurus nigrofuscus
(Forsskal, 1775)
PLATE 129
Brown surgeon
Bruin doktervis
Chaetodon nigro-fuscus Forsskal, 1775: 64 (Red Sea). Acanthums
nigrofuscus: Randall, 1956: 190*; Winterbottom, 1976: 68; Smith, 1980:
179.
D IX,24-27; A 111,22-24; P 16-17. Body depth 2.0-2.3 in SL; 10 upper
and 12 lower jaw teeth at 55 mm SL, and 14 upper and 16 lower teeth at
148 mm SL; C lunate, concavity 4.5-6.0 in SL. Brown to lavender-brown,
with or without fine bluish grey longitudinal lines on body; lips blackish;
prominent black spot larger than Y;. eye diameter at rear end of D base and
a smaller black spot at end of A base; head and chest with numerous small
orange spots (which mayor may not persist as pale spots in preservative);
a distinct narrow whitish border posteriorly on C; a narrow blackish edge
around caudal spine socket.
A small reef species; attains about 20 cm, Indo-Pacific, to
Coffee Bay, Transkei; common off Natal.
243,7 Acanthurus nigrofuscus: 7 cm (Natal).
243.8 Acanthurus nubi/us
(Fowler & Bean, 1929)
PLATE 129
Bluelined surgeon
Bloulyn-doktervis
Hepallls (Harpurina) nubilus Fowler & Bean, 1929: 253, Fig. I:;
(Celebes). Acanlhurus nuhilus: Randall, 1956: 179*.