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Ontogeny of the balashark Balantiocheilos melanopterus Bleeker, 1851 (Cyprinidae)

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The Balashark is a highly praised ornamental species that has been overfished to the point that it has become endangered in most of its distribution area, especially in Indonesian waters. Captive propagation has reduced the threats upon wild populations of balashark. Nevertheless, knowledge on the biology of this species is still scarce, in particular as regards to its ontogeny. This information is crucial for the identification of larvae and small juveniles in the wild, as well as for improving its culture. Balashark eggs average 1.2-1.3 mm in diameter and hatch after 13 hours (26-28°C), giving birth to 4.5-mm embryos, with a yolk sac of circa 1.1 mm3. At the end of the endogenous feeding period (day 4 after hatching [AH]), larvae attain 6.3 mm TL. The mouth opens on day 2 AH (5.8 mm total length, TL). At the time of first feeding (day 4 or 5 AH, 6.3 mm TL), their mouth and gape already average 0.5 mm and 0.27 mm, respectively, and they grow up to 10.2 and 6.3% TL, respectively, on day 8 AH. The swim bladder starts forming as early as day 2 AH and is filled by day 3 AH (5.9 mm TL), but the separation between the anterior and posterior chambers does not take place before 9.5 mm TL (day 9 or 10 AH). The fin development sequence is typical of cyprinids, and follows a caudal-to-cranial pattern (i.e.; caudal, dorsal and anal, pelvic then pectorals), except for the anlagen of pectoral fins, which are present in 1-day old fish (5.3 mm TL). Based on the vanishing of the abdominal and caudal fin fold, and on the lengths of the fins relative to fish size, the transition between the larval and juvenile stage occurs at circa 17 mm TL (corresponding standard length: 13.7 mm). At this stage, the scale cover is not developed yet, but juveniles already exhibit the typical pigmentation pattern of adults on their dorsal, anal, pelvic and caudal fins, while pigmentation on the pelvic fins is still in its very early stages.
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ONTOGENY OF THE BALASHARK Balantiocheilos melanopterus
BLEEKER, 1851 (CYPRINIDAE)
Etienne Baras1,2), Agus Priyadi3), and Marc Legendre1,2)
ABSTRACT
The Balashark is a highly praised ornamental species that has been overfished to the
point that it has become endangered in most of its distribution area, especially in
Indonesian waters. Captive propagation has reduced the threats upon wild populations
of balashark. Nevertheless, knowledge on the biology of this species is still scarce,
in particular as regards to its ontogeny. This information is crucial for the identification
of larvae and small juveniles in the wild, as well as for improving its culture. Balashark
eggs average 1.2-1.3 mm in diameter and hatch after 13 hours (26-28°C), giving birth
to 4.5-mm embryos, with a yolk sac of circa 1.1 mm3. At the end of the endogenous
feeding period (day 4 after hatching [AH]), larvae attain 6.3 mm TL. The mouth opens
on day 2 AH (5.8 mm total length, TL). At the time of first feeding (day 4 or 5 AH, 6.3 mm
TL), their mouth and gape already average 0.5 mm and 0.27 mm, respectively, and
they grow up to 10.2 and 6.3% TL, respectively, on day 8 AH. The swim bladder starts
forming as early as day 2 AH and is filled by day 3 AH (5.9 mm TL), but the separation
between the anterior and posterior chambers does not take place before 9.5 mm TL
(day 9 or 10 AH). The fin development sequence is typical of cyprinids, and follows
a caudal-to-cranial pattern (i.e.; caudal, dorsal and anal, pelvic then pectorals), except
for the anlagen of pectoral fins, which are present in 1-day old fish (5.3 mm TL). Based
on the vanishing of the abdominal and caudal fin fold, and on the lengths of the fins
relative to fish size, the transition between the larval and juvenile stage occurs at
circa 17 mm TL (corresponding standard length: 13.7 mm). At this stage, the scale
cover is not developed yet, but juveniles already exhibit the typical pigmentation
pattern of adults on their dorsal, anal, pelvic and caudal fins, while pigmentation on
the pelvic fins is still in its very early stages.
KEYWORDS: Balantiocheilos melanopterus, cyprinid, ontogeny,
morphology, larva
INTRODUCTION
In the vast majority of fish species, the bulk
of mortality occurs during the early life stages,
both in the wild and in captivity. A series of
species have evolved fast growing strategies
while others have seemingly privileged life
styles that rely on energy conservation, to the
detriment of growth but giving the embryo or
larva the opportunity to survive more or less
prolonged periods of food shortage. In order
to understand to what extent ontogenetic
patterns match environmental constraints, and
thus the threats upon species resilience in
1) IRD (Institut de Recherche pour le Développement), UR 175, Indonesia
2) IRD/GAMET (Groupe aquaculture continentale méditerranéenne et tropicale), UR 175, France
3) Research Institute for Ornamental Freshwater Fish Culture, Depok, Indonesia
man-modified environments, one should be
capable of identifying a particular species at
all stages of its ontogeny. Genetic tools nowa-
days enable the rapid and accurate determina-
tion of fish species, but their application to
broad numbers of fish is tedious and exces-
sively expensive when applied to (very) large
samples, as those needed in ecological stud-
ies, thereby emphasizing the need for thor-
ough morphological descriptions.
These principles have fostered research
on the ontogeny of fish, which was originally
driven by evolutionary purposes, and resulted
Ontogeny of the Balashark .......... (Etienne Baras)
59
in the production of taxonomic guides, which
permit the univocal determination of who is
who for all or most life stages. Generally, these
guides are produced on a river basin (e.g.
Hogue et al., 1976; Margulies, 1983) or coun-
try basis (e.g. Pinder, 2001). The degree of taxo-
nomic resolution may not be as accurate as for
adults or juveniles, essentially because dis-
criminating criteria are generally less obvious
in embryos and larvae than in juveniles or
adults. Nonetheless, ontogeny is a dynamic
process, the description of which may enable
an equally accurate taxonomic resolution if a
sufficient number of traits are under scrutiny.
Currently, such taxonomic guides are not
available for tropical freshwater fish communi-
ties, largely because accurate descriptions of
fish ontogeny are scarce in these regions. The
comparison between the sizes of the data-
bases in FishBase (Froese & Pauly, 2006) and
LarvalBase emphasises this paucity of infor-
mation. The development of aquaculture pro-
duction and research, in which an increasing
number of species are bred and raised in cap-
tivity for bioconservation, ornamental or food
purposes, provides a heuristic context for
bridging this gap and providing information that
might contribute to identify the causes of a
species’ decline and the solutions to be imple-
mented. With aquaculture-bases studies, fish
ontogeny can be traced instead of being in-
ferred from scant captures in the wild. , Experi-
mental facilities give the opportunity of study-
ing live specimens, and thus their colour pat-
terns, which may vanish totally or partly in pre-
served specimens that originate from the wild.
Furthermore, aquaculture-based studies per-
mit studying species that are currently endan-
gered in their natural distribution area without
jeopardizing their populations
Here, we provide the first description of
the ontogeny of the silver shark
Balantiocheilos melanopterus Bleeker 1851
(Cyprinidae), also known as tricolour shark min-
now or balashark in Indonesia. The balashark
is a highly praised ornamental species that has
been overfished to the point that it has be-
come endangered in most of its distribution
area, especially in Indonesian waters (Ng & Tan,
1997).
MATERIAL AND METHODS
The fish that were analysed in this study
originate from broodfish from a Thai popula-
tion of balashark that was introduced in Indo-
nesia. Eggs were obtained following a hormonal
treatment of females (HCG 300 IU.kg-1, then
Ovaprim 0.5 mL.kg-1 of female 5 hours later),
followed by artificial fertilization. Embryos and
larvae were raised in 80-L (100 x 40 x 20 cm)
tanks and fed with brine shrimp nauplii. Water
temperature during the study averaged 26°C
at night and 28°C during the day (12L:12D).
Fish were sampled at daily intervals, transferred
to the LR-BIHAT Depok station, and photo-
graphed under the stereomicroscope (magni-
fication: 8-100 x) and the light microscope for
closer shots, using top, bottom and side views.
Dimensions were measured to the nearest pixel
from digital photographs, by reference to a
graduated scale that was photographed at the
same magnification(s). The morphomeristic
variables under scrutiny were those that are
critical to feeding and locomotion: i.e. fish size
(total, fork and standard lengths), body depth,
fin length and growth of finrays, head width
and length, upper and lower jaw lengths; gape
height was estimated from jaw length, on the
assumption of a 90° opening capacity, which
is a generally used as a standard for describ-
ing the ingestion capacity of fish larvae and
small juveniles (Shirota, 1970).
Additional information was collected on
the rate of yolk absorption and on the
ontogeny of the swimbladder, in particular as
regards the specialisation of the swimbladder
into two distinct chambers, and the variation
of their respective proportions during the
ontogeny. For both structures, the contour was
traced on digital side views of the fish, thereby
enabling the direct calculation of the surface
(pixels), which is later expressed by reference
to the actual size of the fish, so the surface
can be converted into mm2. Thereafter, the
volume is reconstructed from an ellipsoidal
approximation.
RESULTS
Growth. Balashark eggs averaged 1.2-1.3
mm in diameter. They hatched 13 hours after
fertilization (26-28°C), giving birth to embryos
of circa 4.5 mm in total length (TL), with a
yolk sac of circa 1.1 mm3. During the first two
days after hatching (hereafter AH), embryos
absorbed their yolk at a rapid pace (0.36 mm3
day-1) and exhibited fast growth (0.7 mm TL
day-1). During the next two days, the rate of
yolk absorption decreased by circa 50% (0.2
mm3 day-1) and growth slowed down as well
(0.25 mm TL day-1).
Indonesian Aquaculture Journal Vol.2 No.1, 2007
60
Exogenous feeding commenced on day 4
or 5 AH, when larvae averaged 6.3 mm TL. The
growth on the first feeding day was slow (0.3
mm day-1) then it increased rapidly and
averaged 0.7-0.8 mm day-1 during the next 9
days, i.e. almost the same pace as during the
fast growing embryonic period. Thereafter, a
parasitic outbreak took place and compro-
mised growth considerably before it was
mitigated with a 20-ppm formaldehyde
treatment (day 17 AH). Following the treatment,
growth resumed at the same pace as before
the parasitic outbreak and fish attained 17.2
mm TL when aged 23 days AH.
Because the growth of balashark was
slowed down or halted during several days,
no reference to age was attempted for fish
older than two weeks. However, this shortcom-
ing is not of utmost importance since in most
fish species; ontogeny refers most closely to
size than to age, except for the very early life
stages. This was empirically verified in
balashark by comparing the developmental
stages of fish of different ages but of similar
body lengths.
Fins. At hatching, only a continuous, non-
structured finfold was present. It extended
over 58.5 and 51.5% of the embryo’s length on
the dorsal and ventral side, respectively, and
its surface amounted to 0.47 mm2. The next
day (5.2 mm TL), the surface finfold had almost
doubled (0.87 mm2), essentially because of the
development of the anlage of the caudal fin.
Thereafter, the finfold exhibited no further
specialisation until 6 days AH (6.6 mm TL), when
the first finrays of the caudal fin started grow-
ing ventrally. Caudal finrays started differenti-
ating on day 5 AH, before the flexure of the
notochord, which was tenuous (5°) at 7 days
AH (6.9 mm TL) but attained its definitive bend
(32-33°) at 8 days AH (8.1 mm TL). The caudal
fin became forked at 10 days AH. Throughout
this period, the caudal fin length exhibited a
rapid positive allometric growth up to circa
20% TL at 15 mm TL, and a slower growth there-
after, with a maximum of 24% TL in a 75-mm
juvenile.
The finfold of the ventral and dorsal regions
exhibited no specialisation before 7 days AH,
when the anlage of the dorsal fin started dif-
ferentiating. The anlage of the anal fin was not
distinctly shaped before day 9 AH. From these
moments onwards, these two fins exhibited a
rapid allometric growth (Figure 1), which was
supported by the concomitant growth of their
finrays (starting on day 10 AH; Table 1). The
growth of the anal fin became isometric in fish
greater than 17.2 mm TL (circa 8.2% TL) while
the dorsal fin continued its allometric growth
Figure 1. Fin development sequence and growth allometries of fins in Balantiocheilos
melanopterus. In fish less than 8 mm TL, the dimensions given for the dorsal
and anal fins are the heights of the dorsal and ventral finfold, respectively
Fish size (TL,mm)
Dimension (% TL)
Ontogeny of the Balashark .......... (Etienne Baras)
61
and attained 20.2% in the 75-mm juvenile that
was used as a standard in this study.
In regards to the paired fins, the pectoral
fins were absent at hatching but on the next
day, their anlagen had differentiated and al-
ready attained 6.5 % TL. Their growth was faster
than that of other fins, as they attained their
maximum dimension (13.5-14.0 % TL) as early
as 5 days AH (6.3 mm TL). By contrast, the pec-
toral finrays did not develop before the age of
11 or 12 days AH (11.0 mm TL). The anlagen of
the pelvic fins were the last to grow, at 11
days AH, but their finrays elongated rapidly
from the next day. The pelvic fins had attained
their maximal dimension (10.5% TL) at 17.2 mm
TL, a size at which the remnants of the caudal
and abdominal finfold had vanished.
Cephalic region. The length and width of
the head in hatchlings averaged 15.1 and 9.7%
TL, respectively. Both variables showed a rapid
allometric growth during the embryonic period
and attained their largest dimension relative
to body length at the start of exogenous feed-
ing; thereafter, they exhibited an isometric
growth during the rest of the larval and early
juvenile stages.
The gill arches appeared on day 2 AH, while
the opercula did not form before day 4 AH. The
eyes were present at birth, but almost non-
pigmented, except for the lowest margin. Two
days later, the eyes were fully pigmented. The
eye diameter at hatching was 4.1 % TL. There-
after, the eyes exhibited a positive allometric
growth throughout the juvenile and larval
stages and averaged 6.3 % TL at 17.2 mm TL.
A similar ratio was observed in a 75-mm TL
juvenile from an older progeny. The otic
capsule was also present at birth and two
otoliths were clearly visible. One day later, the
semicircular canals had already developed. In
hatchlings, the otic capsule was caudal to the
head (16.3% TL from the snout). On the next
day, it had migrated forward (11.1% TL from the
snout), above the location of the forthcoming
first gill arches. The diameter of the otic
capsule was 2.7% TL at hatching, and increased
rapidly during the next few days, up to a
maximum of 5.6% TL at 5 days AH. Because
of the development of pigmentation, the
ontogeny of the otic capsule could not be
traced later on.
The mouth of balashark was still closed on
day 1 AH, but opened on day 2 AH (5.9 mm TL).
As in most fish species, the lower jaw (LJ) was
originally shorter than the upper jaw (UJ). The
LJ:UJ ratio increased progressively from 72 to
87% at 15 mm TL and then exhibited almost no
or little variation thereafter. Mouth width and
gape (90° opening) at 2 days AH were 6.7 and
3.9 % TL, respectively. Both dimensions exhib-
ited a positive allometric growth during the rest
of the embryonic period (Figure 2), resulting in
absolute dimensions of 0.50 (width) and 0.27
mm (gape) at the start of exogenous feeding.
Both dimensions make it possible for balashark
Table 1. Variations in the number of finrays during the ontogeny of balashark
Balantiocheilos melanopterus. All finrays were fully elongated on day 13 after
hatching (AH). The first ray of the dorsal and anal fins is a supporting ray, which
is at least twice shorter than the second ray, and is noted +1
Age Size
(days AH) (TL, mm)
4 6.3 0 0 0 0 0
5 6.3 4 0 0 0 0
6 6.6 9 0 0 0 0
7 6.9 14 0 0 0 0
8 8.1 19 0 0 0 0
9 8.2 19 0 0 0 0
10 9.9 19 7 2 0 0
11 11 19 8 4 8 9
12 11 19 9+1 6+1 8 9
13 11.8 19 9+1 6+1 8 9
PectoralCaudal Dorsal Anal Pelvic
Indonesian Aquaculture Journal Vol.2 No.1, 2007
62
to ingest large prey, such as brine shrimp nau-
plii (0.6 mm x 0.15 mm in diameter), which were
readily ingested by 5-day old larvae and per-
mitted to fuel a relatively fast growth. The allo-
metric growth of mouth width and gape con-
tinued during the early larval period, until lar-
vae attained 9 mm TL, when the two dimen-
sions averaged 10.2 and 6.3% TL, respectively.
Thereafter, gape remained unchanged while
mouth width exhibited a slightly negative allo-
metric growth that paralleled that of head width.
Thoracic and abdominal region. As
other cyprinids, balashark possess an ill-de-
fined stomach, so the ontogeny of their gut
could not be traced from morphological crite-
ria, contrary to the situation in many other fish
taxa. The swimbladder started forming as early
as day 2 AH and but was not filled before the
next day (5.9 mm TL). The volume of the
swimbladder expanded rapidly from 0.017 to
0.050 mm3 during the next two days. Thereaf-
ter, its growth was isometric (by reference to
the cube of the fish body length) until 17.2 mm
TL (the contour of the swimbladder could no
longer be traced in larger fish because of the
development of the pigmentation pattern and
scale cover). Until day 9 AH, the swimbladder
displayed no specialisation. From day 10 AH
onwards (9.5-9.9 mm TL), the anterior chamber
started differentiating and its volume (relative
to that of the entire swimbladder) increased
rapidly up to 70% at 13 mm TL. Thereafter, this
proportion remained almost stable until 17.2
mm TL (71%; Figure 3).
Body dimensions and pigmentation
pattern. From the size and age when the
caudal fin became forked, the relationships be-
tween the total TL, standard (SL) and fork
lengths (FL) in balashark were described by
simple linear relationships:
FL (mm) = 1.026 [0.077] + 0.755 [0.003] TL (mm)
(R2=0.999, df=16)
SL (mm) = 1.301 [0.068] + 0.818 [0.002] TL (mm)
(R2=0.999, df=16)
SL (mm) = -0.235 [0.045] + 0.924 [0.002] FL (mm)
(R2=0.999, df=16)
Fish body depth at birth was 23.2% TL, but
diminished rapidly as the yolk was absorbed,
and attained 13.2% at the start of exogenous
feeding. Thereafter, it increased in a curvilin-
ear way, up to 16.1% TL at 17.2 mm TL. The
positive allometric growth of body depth pur-
Figure 2. Growth allometries during the ontogeny of Balantiocheilos
melanopterus, focusing on the cephalic region
Fish size (TL,mm)
Dimension (% TL)
4 6 8 10 12 14 16 18
24
22
20
18
16
14
12
10
8
6
4
0
2
Gape
(900)
Head length
Body depth
Head width
Mouth width
Ontogeny of the Balashark .......... (Etienne Baras)
63
sued later on, since it attained circa 22% TL at
75 mm TL. No model is proposed for this vari-
able, because the pathological outbreak that
took place during this study produced a loss
of condition in balashark and caused body
depth to shrink slightly during this period (Fig-
ure 1).
The variation of the pigmentation pattern
during the ontogeny of balashark is illustrated
on plate I. The chromatophores first appeared
above the swimbladder on day 2 AH, then as a
ventral row, below the epaxial and caudal mus-
culature on day 3 AH. Thereafter, chromato-
phores developed in the cephalic region, then
in the fins, either before finrays (caudal),
slightly after finrays (dorsal, anal) or much later
than finrays (pelvic).
DISCUSSION AND CONCLUSION
Based on the criterion of finfold vanishing,
balashark becomes juveniles at a size of circa
17 mm TL or slightly before this. This cut-off
size is also consistent with the growth pat-
terns of fins, which are almost isometric by
then. However, many characters remain to ap-
pear or develop in fish greater than 17 mm TL.
At first, the scale cover has not developed yet,
balashark are still slender and the pigmenta-
tion of the fins is yet to come (pelvic fins) or
expand (caudal, anal, and dorsal). Another no-
table feature is the fact that the first full-length
finray of the dorsal fin is not serrated yet.
The ontogenetic sequence in balashark is
shared by many other fish species, probably
because many species face similar constraints
(i.e. escaping predation and feeding). At first,
developing a more efficient propeller and struc-
tures that provide balance (namely the pecto-
rals), which both permit improving locomotion
and escape from predation. Next the
swimbladder, which provides buoyancy, the
gills, and the mouth and gut, which are propor-
tionally less crucial than other structures while
the fish can still rely on its yolk. Except for the
anlagen of the pectoral fins, which grow from
a very young age, the fin development se-
quence in balashark follows a caudal-to-cra-
nial pattern: i.e. caudal, dorsal and anal, pelvic
then pectoral fins. To the best of our knowl-
edge, all Cypriniformes and almost all Otophysi
exhibit this pattern, with slight variations (i.e.
the anal fin and finrays may grow at the same
time as or slightly after the dorsal fin and
finrays). However, this pattern has also been
reported in a broad series of taxa, and com-
prises over 50% of the species in which this
sequence has been described (circa 800 spe-
cies, E. Baras, unpublished data).
Figure 3. Variation of the volume of the swimbladder and of the
proportion of its posterior (hydrostatic only) chamber
during the ontogeny of Balantiocheilos melanopterus
Fish size (TL,mm)
Volume (mm3) Proportion posterior chamber (% total volume)
Indonesian Aquaculture Journal Vol.2 No.1, 2007
64
Currently, we have not identified any crite-
ria that makes the embryo and larvae of
balashark so typical that could make their iden-
tification straightforward and univocal, as for
example the striped pigmentation pattern of
the clown loach Chromobotia macracanthus
(a cobitid that also originates from rivers and
streams in Sumatra), which appears at a very
early age and is not shared by many species (if
any) in its range (Legendre et al., 2005). None-
theless, this study provided a complete de-
scription of the variations of meristic charac-
ters and relative proportions of a series of
morphometric variables, including some that
are generally neglected, such as the respec-
tive proportions of the two chambers of the
swimbladder. Hopefully, the combination of
these traits will enable the definition of dis-
criminating criteria with other Indonesian fish
species, for which the ontogeny is still to be
scrutinised.
ACKNOWLEDGEMENTS
The authors wish to thank Slamet Sugito,
for technical assistance, Bambang Dwisusilo
for image processing, Chumaidi, Zafril Imran, I.
Wayan Subamia, Jacques Slembrouck and
Laurent Pouyaud for fruitful discussions on the
biology and culture of balashark.
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Ontogeny of the Balashark .......... (Etienne Baras)
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Plate I. Illustration of the ontogeny of Balantiocheilos melanopterus
Indonesian Aquaculture Journal Vol.2 No.1, 2007
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Article
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Article
Full-text available
SoutheastAsia is an area rich in biodiversity, with a high degree ofendemism in both flora and fauna. Many freshwater fish specieshave been exploited for the ornamental fish trade. As thepopulation in South East Asia increases, vast tracts of forestsare cleared for agricultural, industrial and urbanizationpurposes. To conserve and sustainably exploit the wild fishpopulation, measures should be adopted to protect this naturalresource. Already, several ornamental species have been severelyoverexploited, e.g. bala shark (Balantiocheilos melanopterus),pygmy loach (Botia sidthimunki) and arowana (Scleropagesformosus), but the extirpation of local populations occurs formany reasons, including deforestation, and not just because offishing for the trade. There are also still many species thathave great ornamental fish potential. Wild fish species have alsobeen successfully bred in captivity and conserved, e.g. tigerbarb (Puntius tetrazona), bala shark, pygmy loach and arowana.Other methods of conservation include public education, leavingpristine forests intact and reforestation. The aquarium trade ofthe bala shark, harlequin rasbora (Rasbora heteromorpha), clownloach (Botia macracanthus), arowana and sawfish (Pristismicrodon) is discussed
Perkembangan o nto geni larva Chromobot ia macracanthus (populasi Sumatera) Poster presented at the " Seminar Ikan Hias Botia
  • M Legendre
  • H Mundriyanto
  • D Satyani
  • L Pouyaud
  • Sudarto
  • S Sugito
  • J Slembrouck
Legendre M., Mundriyanto H., Satyani D., Pouyaud L., Sudarto, Sugito S. & Slembrouck J., 2005. Perkembangan o nto geni larva Chromobot ia macracanthus (populasi Sumatera). Poster presented at the " Seminar Ikan Hias Botia ", 15 December 2005, Jambi, Indonesia.
A preliminary guide to the identification of larval fishes in the Tennessee River. Division of Forestry, Fisheries and wildlife Development
  • J J Hogue
  • R Wallus
  • L K Kay
Hogue, J.J., Wallus, R. & Kay, L.K. 1976 A preliminary guide to the identification of larval fishes in the Tennessee River. Division of Forestry, Fisheries and wildlife Development, Tennessee Valley Authority, Technical Note B19, 66 pp.
Margulies, D. 1983. A preliminary guide to the identification of families of larval fishes occurring in the Ohio River
  • M Legendre
  • H Mundriyanto
  • D Satyani
  • L Pouyaud
  • Sugito S Sudarto
  • J Slembrouck
Legendre M., Mundriyanto H., Satyani D., Pouyaud L., Sudarto, Sugito S. & Slembrouck J., 2005. Perkembangan o nto geni larva Chromobot ia macracanthus (populasi Sumatera). Poster presented at the "Seminar Ikan Hias Botia", 15 December 2005, Jambi, Indonesia. Margulies, D. 1983. A preliminary guide to the identification of families of larval fishes occurring in the Ohio River. Ohio Journal of Science 83, 135-138.