SCIAENIDAE (KOBS)
head. Body scales ctenoid, those on head cycloid. Three pairs of pores on
lower jaw, the 1st on front of chin minute. Lower jaw not projecting;
maxilla reaches vertical at rear edge of eye. Jaws with 7 or 8 distinctly enlarged teeth on each side of jaws; first 3 on each side of upper jaw exposed
when mouth is closed. Data taken from Trewavas (1977) and 227 mm SL
fish (RUSI 8271) recently collected off the Tugela river in Natal.
Body dusky silver; gill cavity, inside of mouth and lining
of abdominal cavity dusky to black. Attains 30 cm. Natal,
India, Taiwan, China and Japan in 45 - 100 m.
Genus Johnius Bloch, 1793
Soft D and A scaly. Fourth vertebra with inferior
apophyses united below haemal canal to form an arch to
which the hammer-shaped gasbladder is attached. Other
characters of this genus are given at 4b in the key to genera
above. About 18 species, 2 in our area.
KEY TO SPECIES
la Short barbel on chin; outer (enlarged) teeth of
upper jaw not widely spaced; GR (3-5)+(7-10)
including rudiments ......... .............................. 1. amblycephalus
Ib No chin barbel; outer (enlarged) teeth of upper
jaw widely spaced; GR (4-7)+(14-17) including
rudiments ......................................................... 1. dussumieri
Bellfish
199.5 Johnius amblycephalus
(Bleeker, 1855)
Belvis
Umbrina dussumieri Valenciennes, 1833: 481 (Coromandel, India).
Umbrina amblycephala Bleeker, 1855: 412 (Amboina, Moluccas). UmbrinaJuscolineata von Bonde, 1923: 15, PI. 4 (Natal). Sciaena dussumieri:
Smith, SFSA No. 555. lohnius amblycephalus: Trewavas, 1977: 426*.
D IX-XIII,23-27; A II,7; P 18-19; LL48-53; GR (3-5)+(7-10) including
rudiments; length of longest GR is less than diameter of rear nostril.
Depth 3.3-3.7, head 3.1-3.4 in SL; eye 4.5-5.1, longest D spine 1.9-2.4 in
head. Snout short, bluntly rounded; mouth inferior, small (upper jaw
length 2.8-3.0 in head) . Band of cardiform teeth in jaws; outer teeth of
upper jaw enlarged. South African specimens seem to have shorter D
spines than those from India and the Indo-West Pacific region; but as this
is the only difference that is apparent, we follow Trewavas in considering
U. Juscolineata von Bonde a synonym of the widely distributed 1.
amblycephalus.
Attains 23 cm. Indo-West Pacific region; in our area from
Algoa Bay northwards from shore to 50 m.
199.5 Johnius amblycephalus: 13 em SL (off Natal).
618
Small kob
199.6 Johnius dussumieri
(Cuvier, 1830)
Kleinkob
Corvina dussumieri Cuvier, 1830: 119 (Malabar, India). Corvina dorsalis Peters, 1855: 242 (Mozambique). Sciaena parva Gilchrist &
Thompson, 1908: 183 (Natal). Umbrina macroptera (non Bleeker): Barnard, 1927: 581. lohnius (lohnieops) dussumieri: Trewavas, 1977: 437*.
Sciaena macroptera (non Bleeker): Smith, SFSA No. 559.
D IX-XlI,27-30; A II,7-8; P 19; LL 47-49; GR (4-7)+(14-17). Depth
2.8-3.5, head 3.1-3.5 in SL; eye 4.2-5.1, interorbital 3.2-3.5 in head. Body
scales ctenoid; maxilla ends below rear part of eye; upper jaw 40-45%
head length; P much longer than V. First D dusky . Trewavas (1977) recognises 1. (lohnieops) sina and 1. (lohnieops) dussumieri as separate
species, based on the configuration of the snout: "snout decurved, but not
inflated" in the latter species and "inflated" in 1. sina. But she also
describes the snout of 1. dussumieri as "swollen". As we have specimens
that are intermediate between the two types illustrated by Trewavas, we
are forced to conclude that 1. sina is not a valid species.
Attains 23 cm. From East London, South Africa to Singapore.
199.6 Johnius dussumieri: 16 em SL (Great Fish River estuary); gill cover
turned back to show how gasbladder appendages are visible.
Genus Otolithes Oken, 1817
Lower jaw projecting; a pair of very large canines at front
of both jaws. No cephalic appendage of gasbl.adder. Two
species; 1 in our area. O. cuvieriTrewavas, 1974, from India
and Pakistan may reach our area; it has 12-17 lower GR and
moderate canines.
head. Body scales ctenoid, those on head cycloid. Three pairs of pores on
lower jaw, the 1st on front of chin minute. Lower jaw not projecting;
maxilla reaches vertical at rear edge of eye. Jaws with 7 or 8 distinctly enlarged teeth on each side of jaws; first 3 on each side of upper jaw exposed
when mouth is closed. Data taken from Trewavas (1977) and 227 mm SL
fish (RUSI 8271) recently collected off the Tugela river in Natal.
Body dusky silver; gill cavity, inside of mouth and lining
of abdominal cavity dusky to black. Attains 30 cm. Natal,
India, Taiwan, China and Japan in 45 - 100 m.
Genus Johnius Bloch, 1793
Soft D and A scaly. Fourth vertebra with inferior
apophyses united below haemal canal to form an arch to
which the hammer-shaped gasbladder is attached. Other
characters of this genus are given at 4b in the key to genera
above. About 18 species, 2 in our area.
KEY TO SPECIES
la Short barbel on chin; outer (enlarged) teeth of
upper jaw not widely spaced; GR (3-5)+(7-10)
including rudiments ......... .............................. 1. amblycephalus
Ib No chin barbel; outer (enlarged) teeth of upper
jaw widely spaced; GR (4-7)+(14-17) including
rudiments ......................................................... 1. dussumieri
Bellfish
199.5 Johnius amblycephalus
(Bleeker, 1855)
Belvis
Umbrina dussumieri Valenciennes, 1833: 481 (Coromandel, India).
Umbrina amblycephala Bleeker, 1855: 412 (Amboina, Moluccas). UmbrinaJuscolineata von Bonde, 1923: 15, PI. 4 (Natal). Sciaena dussumieri:
Smith, SFSA No. 555. lohnius amblycephalus: Trewavas, 1977: 426*.
D IX-XIII,23-27; A II,7; P 18-19; LL48-53; GR (3-5)+(7-10) including
rudiments; length of longest GR is less than diameter of rear nostril.
Depth 3.3-3.7, head 3.1-3.4 in SL; eye 4.5-5.1, longest D spine 1.9-2.4 in
head. Snout short, bluntly rounded; mouth inferior, small (upper jaw
length 2.8-3.0 in head) . Band of cardiform teeth in jaws; outer teeth of
upper jaw enlarged. South African specimens seem to have shorter D
spines than those from India and the Indo-West Pacific region; but as this
is the only difference that is apparent, we follow Trewavas in considering
U. Juscolineata von Bonde a synonym of the widely distributed 1.
amblycephalus.
Attains 23 cm. Indo-West Pacific region; in our area from
Algoa Bay northwards from shore to 50 m.
199.5 Johnius amblycephalus: 13 em SL (off Natal).
618
Small kob
199.6 Johnius dussumieri
(Cuvier, 1830)
Kleinkob
Corvina dussumieri Cuvier, 1830: 119 (Malabar, India). Corvina dorsalis Peters, 1855: 242 (Mozambique). Sciaena parva Gilchrist &
Thompson, 1908: 183 (Natal). Umbrina macroptera (non Bleeker): Barnard, 1927: 581. lohnius (lohnieops) dussumieri: Trewavas, 1977: 437*.
Sciaena macroptera (non Bleeker): Smith, SFSA No. 559.
D IX-XlI,27-30; A II,7-8; P 19; LL 47-49; GR (4-7)+(14-17). Depth
2.8-3.5, head 3.1-3.5 in SL; eye 4.2-5.1, interorbital 3.2-3.5 in head. Body
scales ctenoid; maxilla ends below rear part of eye; upper jaw 40-45%
head length; P much longer than V. First D dusky . Trewavas (1977) recognises 1. (lohnieops) sina and 1. (lohnieops) dussumieri as separate
species, based on the configuration of the snout: "snout decurved, but not
inflated" in the latter species and "inflated" in 1. sina. But she also
describes the snout of 1. dussumieri as "swollen". As we have specimens
that are intermediate between the two types illustrated by Trewavas, we
are forced to conclude that 1. sina is not a valid species.
Attains 23 cm. From East London, South Africa to Singapore.
199.6 Johnius dussumieri: 16 em SL (Great Fish River estuary); gill cover
turned back to show how gasbladder appendages are visible.
Genus Otolithes Oken, 1817
Lower jaw projecting; a pair of very large canines at front
of both jaws. No cephalic appendage of gasbl.adder. Two
species; 1 in our area. O. cuvieriTrewavas, 1974, from India
and Pakistan may reach our area; it has 12-17 lower GR and
moderate canines.