the green chromide ( etroplus suratensis ) is a species of cichlid fish from freshwater and brackish water in southern india and sri lanka .

other common names include pearlspot cichlid , banded pearlspot , and striped chromide .

in kerala in india it is known locally as the karimeen .

this fish is native to sri lanka and coastal regions of india .

many populations are likely introductions .

it is also introduced in singapore , where it occurs in estuaries .

the adult is oval in shape with a short snout .

it is gray-green in colour with dark barring and a dark spot at the base of the pectoral fin .

it commonly reaches 20 centimetres ( 7.9 in ) in length , and the maximum length is twice that .

this species lives in brackish water habitat types , such as river deltas .

it eats mainly aquatic plants , but it consumes the occasional mollusc , diatoms , and other animal matter .

this species engages in attentive parental care in which several adults care for each brood .

in 2010 this species was named the official state fish of kerala .

the following year was declared " the year of the karimeen " .

karimeen pollichadhu , a fried dish , is a delicacy served in restaurants .

it is familiar to tourists , but because it is very expensive it is not easily accessible to the common man .

production of the species for food is expected to increase in the near future .

they are more closely related to the paretroplus fishes from madagascar .

green chromide

the green chromide has a green or gold tinted oval shaped body with dark vertical bars . there are often gold spots found on the upper half of the body . the green chromide stays slender compared to other cichlid species .
the green chromide ( etroplus suratensis ) is also known by tropical fish keeping enthusiasts as the pearl spot , banded pearl spot , banded chromide , banded etroplus , karimeen , or pearlspot cichlid .
southern india : green chromides are found in the fresh and brackish water habitats .
etroplus suratensis can tolerate freshwater for short periods of time but prefers brackish conditions . use fine sand for the substrate and provide hiding places with caves or wood . open swimming spaces must be provided . green chromide lives in a brackish water . even though they are aggressive in small tanks , they are peaceful in big tanks when there are at least 6 of green chromide fish .
the green chromide has a green , greenish brown , or gold tinted oval shaped body with six dark vertical bars on the body ( excluding those on the head and caudal peduncle ) . gold spots are distributed over the body of the fish , primarily on the upper half .
the green chromide cichlid inhabits brackish estuaries , coastal lagoons , the lower reaches of rivers and a number of freshwater habitats including a number of inland lakes . it is a hardy species that can breath atmospheric air .
green chromide ( etroplus suratensis ) from lim , kelvin k . p . & jeffrey k . y . low , 1998 . a guide to the common marine fishes of singapore . singapore science centre . 163 pp .
it’s sometimes referred to using alternative vernacular names , most commonly ‘pearl spot’ , ‘banded pearl spot’ , ‘banded chromide’ , or ‘karimeen’ .
the green chromide is a relative peaceful species that can be kept in fresh or brackish water aquariums with other asian cichlids , archer fish , or similar sized loaches with the same water parameters . etroplus suratensis can live in freshwater environments , but they prefer brackish water conditions .
compared to other cichlid species , the green chromide keeps a “slender” body profile . although there is no sure visible way to determine the sex of green chromides ; males that are the same age as females tend to be larger and during breeding , the males develop more intense colors and black occipital stripes between the eye and opercle . females will develop a reddish , swollen , modified ovipositor during breeding .
tan heok hui and lionel ng chin soon . 28 oct 2016 . green chromides spawning at sentosa . singapore biodiversity records 2016 : 141 - 142 .
of the ten green chromide fry i obtained about 11 months ago , a pair has formed and they have spawned for the second time . here they are just finishing up , their pink eggs hanging from tiny threads . this second time , the parents chose exactly the same place on an artificial tree stump to deposit them , apparently sensing it to be the safest , most easily defended site .
suneetha gunawickrama , k . b . , 2007 - ruhuna journal of science 2 : 70 - 81 morphological heterogeneity and population differentiation in the green chromid etroplus suratensis ( pisces : cichlidae ) in sri lanka .
quality flakes and pellets can provide the staple diet . vegetable matter should also be given in the form of spinach , peas , and lettuce . green chromides will also accept treats of blood worms and brine shrimp .
green chromides are substrate spawners that may also use caves as spawning sites . wild fish in sri lanka breed twice a year from december to april and again from june to september during the pre monsoon and monsoon seasons . during these periods , water salinity increases and the water becomes cleaner .
green chromide etroplus suratensis family cichlidae updated oct 2016 where seen ? this large colourful fish is often seen in groups in our mangroves at sungei buloh wetland reserve and pasir ris . the fish is native to india and sri lanka and was introduced to singapore , possibly through the aquarium trade . it has since escaped and are now breeding in our waters . features : up to 30cm , usually about 20cm long . oval with a short snout and small mouth . greyish green with 6 to 8 dark bars , a dark spot at the base of the pectoral fins , many scales with a pearly spot . it is sometimes called the pearlspot . what does it eat ? it is mainly herbivorous feeding on filamentous algae , plant material . it may also eat insects . at sungei buloh , often seen nibbling on jetty legs and mangrove roots . baby chromides : several adults may take care of a single brood that presumably were spawned by only two of the adults . human uses : elsewhere , it is raised in aquaculture and also in the aquarium trade .
green chromides are classed as open water spawners but may use caves as their spawning sites . normally the eggs will be deposited on a flat rock which has previously been cleaned by the parents . the eggs should hatch after 36 hours and the fry will be free swimming a few days later . the fry can be fed on newly hatched brine shrimp , rotifers or crushed flake .
: an oval - shaped fish with a pointed head . the coloration is olive green to greenish brown . the body is marked with six to eight transverse bars which may at times , be indistinct . each scale has a golden spot and the fins are body - colored . the anal fins may have some blue iridescence . at spawning times , all the colors are enhanced , making the normal dull - coloring look more impressive .
in an aquarium environment , because they are sexually mature within a year , it is best to place a group of juvenile green chromides together until they pair off . spawning can be induced by gradually increasing the salinity in the breeding tank to replicate the seasonal monsoons . put several flat rocks in the aquarium and slowly increase the salinity in the tank to a brackish level . as the water becomes brackish , pairs will begin digging pits to use as nests .
minimum tank size : 100 gallons care level : moderate temperament : relatively peaceful with similar sized fish aquarium hardiness : moderately hardy water conditions : 72°f - 80°f° f , kh 10 - 25 , ph 7 . 0 - 8 . 0 max . size : 16 inches color form : green , yellow , brown diet : carnivorous compatibility : ok with other asian cichlids or loaches of similar size origin : sri lanka family : cichlidae lifespan : 6 - 12 years aquarist experience level : advanced
is a euryhaline species that inhabits mainly brackish water and river mouths . it is an oval - shaped cichlid with a short snout , small mouth not extending past the front margin of the eye with a greyish - green colouration on the flanks , with 6 to 8 dark bars and a dark spot at base of the pectoral fin . most scales on the sides are with a pearly spot ( costa 2007 ) . macrophytic fragments form the most important component of its diet along with molluscs , although detritus , diatoms , and animal matter are also ingested ( de silva
sides with 6 to 8 dark bars , a dark spot at base of pectoral fin , many scales on sides with a pearly spot . largely herbivorous , in small groups apparently confined to estuaries along north coast of singapore . to 30 cm . popular aquarium fish , introduced ( native to india and sri lanka ) .
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madhusoodana kurup , b . , basheer , v . s . , raghavan , r . & cox , n . a .
etroplus suratensis is assessed as least concern in view of its wide distribution , presumed large overall population , even though it has a relatively declining trend in the wild , in kerala .
is distributed in the coastal regions of peninsular india and sri lanka . in india , the wild populations have been recorded from the states of kerala and tamil nadu . there are also populations in goa , andhra pradesh , orissa and west bengal ( jayaram 1981 & 2010 , biju 2005 ) . these are likely introduced populations ( v . s . basheer pers . comm . ) . the species has now been introduced to dam reservoirs in the mountains and lakes and culture ponds ( rema devi
( 1990 ) . adults engage in altruistic multiple parental care where several adults care for a single brood that presumably were spawned by only two of the adults ( ward and wyman 1977 ) .
etroplus suratensis is a popular foodfish . it is known locally as karimeen and is considered a delicacy . the species has been introduced to various other man - made habitats like tanks , ponds and dam reservoirs for culture and export .
are subject to various pressures brought on by people like habitat deterioration brought on by the disposal of solid and liquid wastes and the discharge of human fecal matter from adjacent habitations and an increasing number of tourism resorts and houseboats , which are going beyond the carrying capacity of the backwaters / estuaries . a major threat is from exotic species like
2009 ) . there have also been reports in the past , of the epizootic ulcerative syndrome ( eus ) disease outbreak , which has been to have spread in south and south - east asia since 1980 ( pathiratne & rajapakshe 1998 ) .
despite the species being in high demand , the wild populations of the species have not been given sufficient conservation attention . there have been attempts in the past to create ' no fishing zones ' within some of the larger estuaries and the species did seek refuge in these protected zones . such no - fishing zones should be extrapolated to other regions as well , to guarantee effective genetic preservation . this is declared as the state fish by the government of kerala . captive breeding has been undertaken by padmakumar et al . ( 2004 ) . an aquatic sanctuary was made in vembanad lake for this species . the vembanad lake protection forums has started ' matsyatavalam ' ( home of fishes ) for the sustainable fisheries of this species . cage culture of this species is being practiced in vembanad lake and vypin islands .
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all time favourite : fishermen in kerala , who have been hit by the trawler ban and bad weather , are trying to make a living by operating in the backwaters where the all - time favourite fish , karimeen , is still available . they fetch anywhere between rs . 120 and rs . 180 a kg . photo : h vibhu
karimeen ( pearl spot ) , the ‘upper - middle class ' fish which is a favourite with tourists , is getting a profile uplift .
kerala fisheries minister s . sarma announced in the assembly this week that the oval - shaped fish , which often serves as kerala ' s icon in the minds of gourmets , will be the official state fish . and , 2010 - 11 is being observed as ‘the year of karimeen . ' the measure is expected to boost the production of karimeen ( etroplus suratensis ) .
already , a dozen states have an official fish . the national bureau of fish genetics resources had in 2008 suggested that states adopt a state fish , à la state bird and animal .
fried pearl spot ( karimeen pollichadhu ) is a delicacy that tops menus at restaurants . few tourists leave without having tasted it . a boat ride in the backwaters while relishing the karimeen pollichadhu is an integral part of an average tourist ' s kerala experience .
however , for the common man , karimeen is too hot a delicacy — it is one of the most expensive fish . karimeen too is beyond the pocket of the poor .
the kuttanad region in alappuzha district is considered the tharavad ( family home ) of the fish . kerala now produces only 2 , 000 tonnes of karimeen . “because of the new initiative , the production is expected to go up to 5 , 000 tonnes in a year , ” fisheries director p . i . sheikh pareeth said .
tojo mathew was leaving the uae for good to join his wife in delhi .
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name from the words ' etron ' meaning belly and ' oplon ' for arms ; referring to the spines on the lower side ; that is , the long spinour anal - fin .
brackish ; benthopelagic ; depth range 10 - ? m . tropical ; 23°c - 26°c ( ref . 2060 ) ; 11°n - 6°s
maturity : l m 15 . 0 range ? - ? cm max length : 40 . 0 cm tl male / unsexed ; ( ref . 41236 ) ; common length : 20 . 0 cm tl male / unsexed ; ( ref . 6028 )
primarily found in brackish water but known to tolerate fresh or marine waters for short periods ( ref . 48490 ) . found in large rivers , reservoirs , lagoons and estuaries . feed on filamentous algae , plant material and insects .
after spawning , about 500 eggs are laid and attached to a submerged log , rock or sometimes roots and weeds , in still or slow flowing water . parents guard and fan the eggs until hatching , usually about 4 days . the fry shoal around their parents during the first weeks of growth . parents refrain from feeding from the time of spawning until the fry become independent .
pethiyagoda , r . , 1991 . freshwater fishes of sri lanka . the wildlife heritage trust of sri lanka , colombo . 362 p . ( ref . 6028 )
phylogenetic diversity index ( ref . 82805 ) : pd 50 = 0 . 6250 [ uniqueness , from 0 . 5 = low to 2 . 0 = high ] .
bayesian length - weight : a = 0 . 01660 ( 0 . 00974 - 0 . 02827 ) , b = 2 . 94 ( 2 . 79 - 3 . 09 ) , in cm total length , based on lwr estimates for this species & ( sub ) family - body ( ref . 93245 ) .
trophic level ( ref . 69278 ) : 2 . 9 ±0 . 26 se ; based on food items .
resilience ( ref . 69278 ) : medium , minimum population doubling time 1 . 4 - 4 . 4 years ( tm = 2 ) .
vulnerability ( ref . 59153 ) : low to moderate vulnerability ( 32 of 100 ) .
from the day we opened the first store in maidenhead , we’ve firmly believed that one key to our success is employing fish keepers .
no obvious external differences . when spawning , it may be possible to observe the more pointed genital papillae of the male .
: to 18
( 46 cm ) in nature , although not larger than 12
( 30 cm ) in aquaria .
: southeastern asia ; lives in brackish water river estuaries and moves in schools between pure freshwater and sea water at different times during the year .
: a 45 - 55 gallon ( 170 - 209 l ) or 40 ( 101 cm ) is sufficient for fish under 8
( 20 cm ) in length . adult fish need at tank of at least 56
( 142 cm ) or 75 gallons ( 285 l ) to prosper . use a substrate of coral sand or less ideally , fine gravel . the tank can be well - planted with large , robust plants , although this species is a known plant eater . provide hiding places and retreats with large caves and wood . leave open swimming areas .
: ph 7 - 9 ( 8 . 0 ) , 12 - 30 dh ( 20 ) , 73 - 81°f ( 23 - 27°c ) . a 1 to 1 . 5 % addition of sea salt is necessary . to obtain this dilution rate see suggestions under
: a shoaling fish that should be kept in groups of at least 6 fish . in smaller schools , quarrels may break out . this fish may be more suitable to salt water community tanks than freshwater tanks . this fish can be kept with other brackish water species including
, crustaceans , insects ; chopped meat ; pellets ; large flakes ; oatmeal ; plant matter ; vegetables ; spinach , peas , lettuce .
sex : the only definite difference is the shape of the genital papilla which is visible at spawning times .
: an open water spawner that lays up to 1000 eggs on a previously cleaned rock or in a cave . they hatch in 36 to 50 hours and are carefully guarded by the parents . the young are free - swimming after 7 - 8 more days . start feeding with
nauplii , roftiers , and dry foods . the young are susceptible to fungal infections if kept in freshwater , and are difficult to raise even in brackish water . their coloring is different from that of the adults . they have a single transverse band around the mid - section . this band disappears , and for several weeks the fry are just silver . eventually they develop the adult coloring .
: sexually mature from 6
( 15 cm ) . this fish ' s colors are enhanced when they are kept in pure sea water .
: 6 . a large fish that needs to be kept in brackish water .
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on this site .
jungle
is generally not used .
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specimens collected by fishermen in chilika lake in odisha state , india , the world ' s second largest coastal lagoon .
etroplus : from the ancient greek ἦτρον ( etron ) , meaning ‘belly , lower abdomen’ , and ὅπλον ( hoplon ) , meaning ‘weapon , armour’ , in reference to the prominent spinous anal - fin rays in members of the genus .
suratensis : named for the type locality “suratte” , now the city of surat .
generally considered native to peninsular india and sri lanka although some sources state that it is only native to sri lanka and was introduced to india for aquaculture purposes in 1950 .
given that it was described from india in 1790 this would seem unlikely , however , and one of the publications often quoted ( welcomme , 1988 ) refers only to ‘aquaculture and stocking lakes’ in 1950 , suggesting it was simply introduced to land - locked freshwater environments at that time .
in addition day ( 1877 ) wrote “i have taken it inland in the wynaad” , i . e . , wayanad district in northeastern kerala .
in india its range stretches southwards down the western coast from the state of gujarat through maharashtra , goa , karnataka , and kerala states as far as the southern part of the peninsula in tamil nadu state .
there also exist records from andhra pradesh , odisha and west bengal states on the eastern coast with these populations also thought to have been introduced for aquaculture .
occurrences in sri lanka are mostly limited to the western coast and pertain to north , north western , north central , western and southern provinces but there is at least one record from batticaloa in eastern province suggesting it might be distributed around much of the island .
e . suratensis has also been introduced to peninsular malaysia and singapore where feral populations appear to be thriving .
type locality is ‘suratte , india , 21°12’n , 72°55’e’ , referring to modern - day surat which lies on the lower tapti river in gujarat state , western india .
this species is euryhaline and mostly inhabits brackish estuaries , coastal lagoons and the lower reaches of rivers .
it also occurs in freshwater habitats , however , including a number of inland lakes in sri lanka although it appears to have been introduced intentionally .
there exists observational evidence to suggest that it can breathe atmospheric air to an extent , probably an adaptation to conditions of low dissolved oxygen .
the congener e . maculatus typically occurs in the same habitats and there exists evidence to suggest that this sympatry is not random and may represent a mutually beneficial relationship with a little cheating on the part of e . maculatus ( see ‘notes’ ) .
this is a gregarious species that is best - maintained in a sizeable group ( see ‘behaviour and compatibility’ ) meaning only the very largest home aquaria or public installations are suitable for long - term care .
this species can be maintained in fresh or brackish water so long as acidic conditions are avoided .
décor is largely down to personal choice although a degree of structure , perhaps incorporating a sandy substrate , variably - shaped rocks and some driftwood branches , would adequately simulate natural conditions .
it is intolerant to accumulation of organic pollutants and requires spotless water meaning weekly water changes of 25 - 50 % volume should be considered routine .
ph : 7 . 0 – 8 . 5 , although in sri lanka it has been recorded in brackish lagoons where the salinity ranges from 0 . 02 to 28 . 00 with ph values of 5 . 0 to 9 . 6 .
observations of wild fish suggest it to be something of a generalist with a tendency to graze aufwuchs and filamentous algae from solid surfaces .
the stomachs of feral specimens in singapore were found to contain detritus , most of the algae groups , crustacean larvae and appendages , animal and plant organic matter , and sand , for example , while the fish themselves were seen biting at floating twigs , grazing submerged plant roots , the bottom of sluice gates and the sides of submerged pillars .
in the aquarium it can be offered high quality prepared foods but displays a preference for small live or frozen items such as chironomid larvae ( bloodworm ) , tubifex , artemia , mosquito larvae , etc .
at least some of the dried products should contain a significant proportion of vegetable matter such as spirulina or similar , while chopped peas and suchlike are also useful supplements .
relatively peaceful unless breeding and will not predate on any but the smallest fishes .
in a community setting the addition of a group or two of gregarious , pelagic species to act as ‘ dithers ‘ is recommended .
in freshwater cyprinids such as certain dawkinsia , devario or rasbora spp . are ideal for this purpose while in the brackish aquarium salt - tolerant poeciliid livebearers , e . g . , poecilia sphenops , can be used .
best avoided are territorial or otherwise aggressive species , including other cichlids unless the aquarium is very large , and those that require soft , acidic water .
etroplus species are loosely gregarious and tends to form groups unless spawning with juveniles in particular displaying a strong social response when threatened .
a group of 8 + individuals should therefore be the minimum purchase and these will form a noticeable dominance hierarchy once sexual maturity is reached .
when maintained in smaller numbers weaker specimens can become the target of excessive abuse by dominant individuals or the group may fail to settle and behave nervously .
males tend to be larger than females of equivalent age but sexing of non - nuptial individuals can be tricky .
in nuptial males the colour pattern becomes generally more intense and this is normally accompanied by the appearance of black occipital stripes between the eye and opercle .
the genital papillae in males is longer and more pointed than of females in which it is broader and rounder .
in nuptial females the papillae becomes reddish , swollen and appears modified into an ovipositor .
this species is a biparental substrate spawner which forms temporary pair bonds when reproductively active .
observations of wild fish in sri lanka suggest that there are two such periods each year represented by the dry pre - monsoonal ( december to april ) and monsoonal ( june to september ; the monsoon season is dry in parts of sri lanka ) seasons when water salinity increases and turbidity decreases , the latter thought to benefit the fish via improved visual contact between adults and fry .
adult e . suratensis were not observed to forage during broodcare , both remaining with the eggs and subsequently fry at all times .
this allowed them to select spawning sites with better chances of fry survival whereas during peak breeding season ( july ) e . maculatus laid its eggs in sparser vegetation and exhibited colonial reproductive behaviour , seemingly a ‘trade - off’ between fry protection and food for the adults .
the benefit of the latter behaviour is that one parent would normally remain with the brood while the other left the territory to forage with the roles reversed every few minutes , thus reducing the amount of time and energy devoted to fry care by half compared with e . suratensis but increasing the risk of predation .
in the aquarium it’s recommended to purchase a group of fish and allow them to select their own partners with young fish normally sexually mature by the age of a year .
during courtship a particular site , normally a rock although even the aquarium glass will do , is selected and the surrounding area defended against intruders from that point on .
eggs are deposited in typical fashion and attached via short filaments permitting a degree of movement .
both parents participate in guarding the territory and general brood - care such as fanning and mouthing the eggs to keep them sediment - free .
incubation is approximately 48 - 72 hours depending on temperature with the fry swimming freely in a further 3 - 4 days .
prior to hatching the adults excavate a number of nursery pits in the substrate surrounding the spawning site and the fry are moved between these until their yolk sacs are absorbed .
if the fry remain with the adults they will graze on their parents’ body mucus when they are 1 - 3 days free - swimming .
parental care normally extends until the fry are 30 - 40 mm in length .
some breeders prefer to remove the eggs prior to hatching as they ‘re often eaten by tankmates or the parents themselves , with the most common method being to remove the rock with eggs attached and place it in a separate container with water from the adults’ tank .
water movement across the eggs is maintained by placing an air - line or filter outlet close to the rock while any displaying signs of fungus should be removed as they’re noticed .
once free - swimming the fry are large enough to accept artemia nauplii and similar immediately .
this species is not especially popular in the aquarium hobby but is an important food fish across the majority of its range with some populations having crashed since the turn of the 21st century due to over - exploitation .
it exhibits a widespread sympatry with the congener e . suratensis throughout its natural range and observations of wild fish provide evidence of a symbiotic relationship between the two in the tidal negombo lagoon , southwestern sri lanka .
e . maculatus acted as a cleaner for the larger e . suratensis , removing parasites and suchlike by grazing the body and fins but the nutrition these provide is considered debatable and therefore not the benefit gained from the task .
more remarkably , the advantage to e . maculatus is hypothesised to be overall health , and therefore reproductive success , of e . suratensis because it is an active predator of its relative’s offpsring .
groups of e . maculatus were seen consuming entire batches of e . suratensis eggs and fry while the latter displayed an apparently altruistic behaviour in which adult individuals unrelated to the parents would help defend the territory .
etroplus is the only cichlid genus native to the indian subcontinent and sri lanka and currently comprises three species among which e . canarensis is uniquely limited to freshwater and restricted in range while e . maculatus and e . suratensis are euryhaline and relatively widespread .
e . maculatus can easily be told apart from the others since dark markings on the body are reduced to 1 - 3 dark blotches just above midbody ( unless stressed when short bars may appear in the upper portion of the body with a solid dark posteroventral patch ) and is much paler overall , with the majority of body scales having an orange - red centre .
the remaining species both possess a series of normally 6 dark vertical bars on the body ( excluding those on the head and caudal peduncle ) but in e . canarensis the anterior 3 bars tend to bifurcate as the fish mature , base body colour is buff - grey , and some body scales have a yellowish central patch , whereas in e . suratensis the bars remain solid throughout life , base body colour is greenish - brown , and numerous body scales have a pearly - white central spot .
e . suratensis is also much the larger fish and capable of exceeding 300 mm sl .
its closest relative among other cichlids is the malagasy endemic genus paretroplus and these two are sometimes grouped together under the putative subfamily etroplinae .
they are an ancient , morphologically distinct lineage and represent the evolutionary sister group to all other cichlids ( sparks and smith , 2004 ) with several unique specialised characters ( sparks , 2001 ; stiassny et al . , 2001 ) .
these include complex paired anterior swim bladder chambers that are located within enlarged exoccipital recesses forming a direct otophysic ( mechanical ) connection between the gas bladder and inner ear , highly modified supraoccipital and exocippital bones of the neurocranium , and specialized ligaments associated with the suspensorium and oral jaws .
etroplus can be told apart from paretroplus by a number of characters including : possession of tricuspid ( vs . unicuspid in paretroplus ) teeth ; teeth present in multiple rows in both upper and lower jaws ( vs . a single row of teeth in upper and lower jaws ; teeth numerous in both upper and lower jaws ( vs . teeth few in number ( < 18 in upper jaw , < 14 in lower ) ; paired anterior gas bladder extensions rather typical and tubelike ( vs . paired anterior gas bladder extensions highly - modified with multiple anterior polyplike chambers possessing a tough and thickened tunica externa , and extremely narrow connections ( diverticula ) to the main gas bladder chamber ) ; an elevated number of anal - fin spines ; configuration of the anal - fin pterygiophore ⁄hemal spine complex ( sparks , 2001 ; stiassny et al . , 2001 ) .
bloch , m . e . , 1790 - berlin : i - xii + 1 - 128 , pls . 217 - 252 naturgeschichte der ausländischen fische v . 4 .
day , f . , 1877 - william dawson & sons , london : 369 - 552 the fishes of india ; being a natural history of the fishes known to inhabit the seas and fresh waters of india , burma , and ceylon . part 3 .
de silva , s . s . , p . maitipe , and r . t . cumaranatunge , 1984 - environmental biology of fishes 10 ( 1 - 2 ) : 77 - 87 aspects of the biology of the euryhaline asian cichlid , etroplus suratensis .
ng , t . h . and h . h . tan , 2010 - journal of fish biology 76 ( 9 ) : 2238–2260 the introduction , origin and life - history attributes of the non - native cichlid etroplus suratensis in the coastal waters of singapore .
padmakumar , k . g . , l . bindu and p . s . manu , 2012 - journal of biosciences 37 ( 1 ) supplement : 925 - 931 etroplus suratensis ( bloch ) , the state fish of kerala .
samarakoon , j . i . , 1983 - mahagasar – bulletin of the national institute of oceanography 16 : 357 - 362 breeding patterns of the indigenous cichlids etroplus suratensis and etroplus maculatus in an estuary in sri lanka .
sparks , j . s . , 2008 - bulletin of the american museum of natural history 314 : 1 - 151 phylogeny of the cichlid subfamily etroplinae and taxonomic revision of the malagasy cichlid genus paretroplus ( teleostei , cichlidae ) .
sparks , j . s . , and w . l . smith , 2004 - cladistics 20 : 501 - 517 phylogeny and biogeography of cichlid fishes ( teleostei : perciformes : cichlidae ) .
ward , j . a . and j . i . samarakoon , 1981 - environmental biology of fishes 6 ( 1 ) : 95 - 103 reproductive tactics of the asian cichlids of the genus etroplus in sri lanka .
ward , j . a . and r . l . wyman , 1977 - environmental biology of fishes 2 ( 2 ) : 137 - 145 ethology and ecology of cichlid fishes of the genus etroplus in sri lanka : preliminary findings .
welcomme , r . l . , 1988 - fao fisheries technical paper 294 : 1 - 318 international introductions of inland aquatic species .
it is native to sri lanka and possibly peninsular india , peninsular malaysia and singapore however , it is believed to have been introduced to india and malaysia for aquaculture in the early 1950s .
because of their size , they need a large aquarium of at least 100 gallon capacity with a fine sand or gravel substrate , lots of rock caves and driftwood for them to hide among , and plenty of open swimming space . they are a shoaling species and in an aquarium environment should be housed with at least 8 or more of their own kind to minimize any aggressive behavior . they become aggressive and will eat smaller tank mates when confined in a smaller sized aquarium .
once the pair select a rock or other site to lay their eggs on , they will defend the surrounding area against all intruders until the eggs are deposited . the female will deposit her eggs on the flat rocks where they are attached to the substrate with short filaments and will hatch , depending on water temperature , within 48 to 72 hours .
after the fry have hatched out , the parents will move the fry for their protection , to the “nursery pits” that they excavated around the spawning site until their egg sacs are absorbed and they become free swimming ( in about 3 to 4 days ) .
during this time , like discus , the fry remain with the adults and will graze on their parents’ body mucus until they are fully free swimming . the fry can be then be fed newly hatched baby brine shrimp , rotifers , or finely crushed flake food . both parents stay with the eggs and brood at all times until they are capable of fending for themselves .
adult etroplus suratensis are easy to feed and will accept a quality flake and pellet food as a staple diet , along with vegetable matter in the form of lettuce , spinach , peas , spirulina wafers , and fresh , frozen or freeze dried bloodworms and brine shrimp .
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usual size in fish tanks : 25 - 30 cm ( 9 . 84 - 11 . 81 inch )
recommended water hardness ( dgh ) : 12 - 26°n ( 214 . 29 - 464 . 29ppm )
rather don’t breed your fish if you don’t know what to do with fry .
if you’re about to breed some fish , get parents from different sources to avoid inbreeding .
pufferfish often look cute , however they’re predators and often kill tankmates as they mature ( there are exceptions ) .
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unfortunately this page doesn ' t allow discussion . please , find any other page that fits your area of interest as over 99 % of our pages allow discussion . the reason why no discussion is allowed here is this page is too general . thanks a lot for understanding ! click here to search , please !
among mangrove roots . pasir ris park , feb 12 nibbling on mangrove roots . pasir ris park , feb 12
pearlspot ( etroplus suratensis ) from fishbase : technical fact sheet on the family , including fact sheets on the species .
backyard farm aquaculture ( ras ) vlog . . moving the fish , feed rates , ph & cycling the system . .
can only be sexed when spawning by viewing the shape of the genital papilla .
undemanding cave spawners . female lays up to 200 small eggs ( 1 - 1 . 5 mm ) inside large flower pot or similar . both parents tend the eggs .
the female secretes a mucus layer on her sides , which the fry feed on . large clutches will sometimes cause damage to mother ' s skin and scales . eventually she chases them away at a size of 10 - 12mm .
the other adults generally stay out of the way and do not molest the youngsters much as they grow , but older juveniles will sometimes eat a complete batch of eggs or fry .
this is a shoaling fish that should be kept in groups of 6 or more . smaller groups can result in the fish fighting amongst themselves . can be kept with other peaceful but robust brackish tank mates such as
feed often with diverse vegetable matter such as frozen chopped spinach , peas or grated carrot . some flake and pellet food is appropriate but minimize protein to avoid overloading the filter .
water with good filtration and aeration . salt can inhibit good filter function so plan excess capacity .
salt levels should be about 1 / 10 of normal sea - salt concentration . use only aquarium - grade sea salt and not food - grade . increased salt levels can help fight / prevent infection , but reduce filter efficiency . ones suited to complete freshwater are available .
they tend to swim in circles so tank width is important - 60cm ( 23 . 6
) x 60cm ( 23 . 6
) x 90cm ( 35 . 4
) minimum tank size for a group of six .
some references cite sizes up to 40cm ( 15 . 7
) , but even large installations such as the london aquarium include few specimens over 20cm ( 7 . 9
) .
this page was last edited on 13 december 2017 , at 02 : 49 .
content is available under creative commons attribution - sharealike 3 . 0 unported license unless otherwise noted .
carnivorous - does well with flake or pellet foods supplimented with frozen or live worms .
other asian cichlids or loaches of similar size ; other fish with similar water parameters .
to induce breeding , put several flat rocks in the aquarium and slowly increase the salinity of your aquarium to a brackish level . once the water has become brackish , pairs will begin digging pits to use as nests . the female will lay the eggs on the flat rocks or another flat surface ) . after the fry have hatched , the parents will move them to the nesting area for protection .


synodontis budgetti , known as budgett 's synodontis , is a species of upside-down catfish native to benin , cameroon , central african republic , côte d'ivoire , mali , niger , and nigeria where it occurs in lake nokoue and the niger .

it was first described by belgian-british zoologist george albert boulenger in 1911 , from specimens collected in lokoja , nigeria .

the species name budgetti comes from name of the collector of the original specimen , j.s. budgett .

synodontis budgetti

lateral view of synodontis ornatipinnis , illustrating the striking patterns seen in some species of synodontis ; cu 91403 . ©
synodontis
may also squeak when they are taken out of the water .
a comparative study of the effect of six different preservation techniques was carried out using two fish species : synodontis budgetti and clarias gariepinus for four weeks . the results revealed that there was a significant loss in crude protein and a considerable gain in fat contents ( p < 0 . 05 ) in all thed preservation techniques . the highest loss in protein was recorded in refrigerated synodontis budgetti with 14 % , while the least loss in protein was recorded in oven dried sample with 6 . 11 % . there was no significant loss in ash and nitrogen free extract ( nfe ) , during the study period . it is concluded that it is best to consume fresh fish as protein deterioration occurred in all the preservation techniques employed in this study .
gonadal development , fecundity and spawning pattern of synodontis schall ( pisces : mochokidae ) from jamieson river , nigeria .
gonadal development , fecundity and spawning pattern of synodontis schall ( pisces : mochokidae ) from jamieson river , nigeria . | open access journals
in this study , the sex ratio of 1 : 1 . 35 in favour of females is similar to that reported for synodontis schall in asa lake , ilorin [ 10 ] . however , imevbore observed almost equal proportion of male and female for s . gambiensis ( i : i ) , hemisyonodontis membraceous ( i : i ) , s . budgetti ( 1 : 050 ) and s . violaceous ( 1 : 077 ) from river niger [ 17 ] . according to araoye , a higher female population can reduce competition among males for courtship activities with the females during the season of reproduction [ 10 ] .
musschoot , t . , and p . lalèyè . 2008 . designation of a neotype for synodontis schall ( bloch and schneider , 1801 ) and description of two new species of synodontis ( siluriformes : mochokidae ) . journal of natural history 42 ( 17 - 18 ) : 13031331 .
synodontis : from the greek syn , meaning together , and odontos , meaning tooth ; in reference to the closely - spaced lower jaw teeth .
fossil mochokids , of the genus synodontis , have been found in deposits from eastern and northern africa dating to at least the early miocene ( at least 20 mya ) ( stewart , 2001 ) . interestingly , fragments of pectoral spines of synodontis dating from the early oligocene have been found in oman , an area where mochokids do not exist today ( otero & gayet , 2001 ) . fossil mochokids outside of the genus synodontis are presently unknown .
6a . eyes with free orbital margin ; 17 principal caudal - fin rays ( only 13 in synodontis contracta ) ; tail forked ; 6 to 10 pectoral - fin rays ( usually 8 or 9 ) ; lateral mandibular barbels with single , gracile branches at each point along length or doubly branched ( fig . 27a–b ) … synodontis
olatunde aa . some aspects of the biology of synodontis schall ( bloch and schneider 1801 ) in zaria . j aquatic sci . 1989 ; 4 : 49 - 54 .
day , j . j . , and m . wilkinson . 2006 . on the origin of the synodontis catfish species flock from lake tanganyika . biology letters 2 : 548552 .
bishai h . m . and y . b . abu gideiri . 1968 . studies on the biology of genus synodontis at khartoum . iii . reproduction . hydrobiologia 31 : 193202 .
sanyanga , r . a . 1998 . food composition and selectivity of synodontis zambezensis ( pisces : mochokidae ) in lake kariba , and the ecological implications . hydrobiologia 361 : 8999 .
willoughby ng . the buoyancy and orientation of the upside - down catfishes of the genus synodontis ( pisces : siluroidei ) . j zool . 1976 ; 80 : 291 - 314 .
araoye pa , jeje cy . the diet of synodontis schall ( bloch and schneider 1901 ) in asa dam , ilorin . nigerian j sci . 1999 ; 33 : 67 - 76 .
bishai h . m . and y . b . abu gideiri . 1965a . studies on the biology of genus synodontis at khartoum . i . age and growth . hydrobiologia 26 : 8597 .
bishai h . m . and y . b . abu gideiri . 1965b . studies on the biology of genus synodontis at khartoum . ii . food and feeding habits . hydrobiologia 26 : 98113 .
most medium or large community fish . although commonly available as such , not a good species for the small community tank . anything smaller than 3foot / 1 meter long , go for synodontis nigriventris instead .
wright , j . j . and l . m . page . 2006 . taxonomic revision of the lake tanganyikan synodontis ( siluriformes : mochokidae ) . the bulletin of the florida museum of natural history 46 : 99154 .
synodontis is a common mochokid genus in many lakes and rivers in tropical africa [ 1 ] . in nigeria , there are about 18 species and these are of great commercial importance [ 2 , 3 , 4 ] .
araoye pa . morphology of the gonads in the reproductive cycle of synodontis schall ( pisces : mochokidae ) in asa lake ilorin , nigeria . j aquatic sci . 2001 ; 16 ( 2 ) : 105 - 110 .
synodontis schall is widely distributed and abundant in the jamieson river , a tributary of the coastal benin river in the niger - delta . they are tasty , much cherished by the local riverine inhabitants and supports a thriving fisheries .
wright , j . j . and l . m . page . 2008 . a new species of synodontis ( siluriformes : mochokidae ) from tributaries of the kasai river in northern angola . copeia 2008 ( 2 ) : 294300 .
halim aia , guma ' a sa . some aspects of the reproductive biology of synodontis schall ( bloch - schneider , 1801 ) from the white nile near khartoum . hydrobiologia . 1989 ; 179 ( 3 ) : 243 - 251 .
sadiku soe , olademeji aa . relationship of proximate composition of lates niloticus ( l ) synodontis schall ( bloch and schneider ) and sarotherodon . galilaeus . nigerian j fisheres . 1991 ; 2 / 3 ( 1 ) : 219 - 244 .
koblmüller , s . , c . sturmbauer , e . verheyen , a . meyer , and w . salzburger . 2006 . mitochondrial phylogeny and phylogeography of east african squeaker catfishes ( siluriformes : synodontis ) . bmc evolutionary biology 6 : 49 .
adedeji ra , araoye pa . study and characterization in the growth of body parts of synodontis schal ( pisces ; mochokidae ) from asa dam ilorin , nigeria . nigerian j fisheres . 2006 ; 2 / 3 ( 1 ) : 219 - 214 .
oni sk . , olayemi jy , adegboye jo . comparative physiology of three ecologically distinct fresh water fishes , alestes nurse : reppell , synodontis schall bloch and schneider and tilapia zilli : gervais . j fish biol . 1983 ; 22 : 105 - 109 .
synodontis : from the greek syn , meaning together , and odontos , meaning tooth ; in reference to the closely - spaced lower jaw teeth . this specific epithet literally means beautiful ( eu - = beautiful , good ) wing ( pteron = wing ) .
friel , j . p . , and j . p . sullivan . 2008 . synodontis woleuensis ( siluriformes : mochokidae ) , a new species of catfish from gabon and equatorial guinea , africa . proceedings of the academy of natural sciences of philadelphia 157 : 312 .
friel , j . p . and t . r . vigliotta . 2006 . synodontis acanthoperca , a new species from the ogôoué river system , gabon with comments on spiny ornamentation and sexual dimorphism in mochokid catfishes ( siluriformes : mochokidae ) . zootaxa 1125 : 4556 .
de weirdt , d . , e . vreven , and y . fermon . 2008 . synodontis ngouniensis , a new species ( siluriformes : mochikidae ) from ngounié and nyanga basins , gabon and republic of congo . ichthyological exploration of freshwaters 19 ( 2 ) : 121128 .
nine genera and approximately 200 valid species are currently recognized . some fossilized pectoral spines have been attributed to synodontis , but none of them are described as new . phylogenetic relationships among the mochokid genera were investigated by vigliotta ( 2008 ) who found that chiloglanis is possibly a paraphyletic assemblage , that synodontis must include s . membranaceous and s . batensoda ( formerly placed in hemisynodontis and brachysynodontis respectively ) and that the reciprocal monophyly of atopochilus and euchilichthys are questionable at best ; all remaining genera are recovered as valid and monophyletic . the general relationships between mochokid genera are illustrated in the phylogeny below .
even more peculiar is the habit of some species of synodontis that are known to swim upside - down . this habit seems to be correlated with feeding while upside - down at the water’s surface ( bishai & abu gideiri , 1965b ) , but upside - down catfishes will rest and swim in the inverted position on a regular basis . chapman et al . ( 1994 ) showed that an upside - down posture near the surface also facilitates respiration in poorly oxygenated water . while the genus synodontis presents the most well - known species with their fascinating behaviors and natural histories , the family is actually much more interesting when taken as a whole .
beyond information gleaned from captive breeding of certain species of synodontis , very little is known about reproduction in mochokids . the best studied mochokids in this regard are most likely nile river synodontis ( including s . membranacea and s . batensoda , previously placed in other genera ) . still , details are limited ; the studies indicate that spawning occurs from july to october , which coincides with the flooding season , and that pairs swim in unison during spawning bouts ( bishai & abu gideiri , 1968 ) . the most interesting and detailed information on mochokid reproduction relates to a species from lake tanganyika , synodontis multipunctatus , which is a brood parasite of mouth brooding cichlids such as simochromis and haplochromis ( sato , 1986 ; wisenden , 1999 ) . adults of this species spawn in the midst of spawning cichlids and the fertilized catfish eggs are taken into the mouth of a cichlid . the catfish eggs hatch first and will eat the host eggs before they leave the host mouth . most amazingly , this species has been able to parasitize mouth brooding cichlids from south america in captivity ( loiselle , 1998 ) .
based largely on coloration and pattern some scientists and aquarists have recognized ‘species flocks’ of synodontis . the largest and most visually impressive of these is the lake tanganyika synodontis species flock . the flock consists of at least six species , all endemic to the lake , that show amazingly similar coloration and patterning . recent work suggests that this ‘flock’ is not monophyletic and that the biogeographic scenario is more complicated than a simple radiation after lake formation ( day & wilkinson , 2006 ; koblmuller et al . , 2006 ) . regardless , in this group of species , the nearly constant color pattern consists of a light brown base color and darker brown polka - dots . it is made more impressive by the fins , which have dark brown membranes basally and stark white trailing edges . the cryptic nature of lake tanganyika synodontis has led to an underestimate of the actual number of species present ( wright & page , 2006 ) ; three new species were described and two others were resurrected in that work . there are several other smaller flocks with their own unique patterns and pigmentation outside of the lake , and cryptic species probably exist for these as well .
the testicular and ovarian cycle of synodontis schall in this investigation can be divided into five stages - immature , recovery , maturing , ripe and spawning . all the gonad stages showed visible morphological and histological changes during development . these changes , which occurred during the maturation processes , conformed to the general pattern of development of the gonads in most teleosts [ 18 , 19 , 20 ] .
dorsal view of heads illustrating sexual dimorphism of the opercular spine in synodontis acanthoperca : a . cu 89005 , male holotype , 44 . 1 mm sl ; b . cu 89006 , female paratype , 40 . 4 mm sl . the pectoral spines in both specimens have been removed from the images to make the margins of the head more distinct against the background . scale bar equals 1 mm . ©
little is known about the ecology of most mochokids . what is known pertains mostly to diet and is biased towards species of synodontis . stomach contents from synodontis have included insects , nematodes , crustaceans , mollusks , annelids , seeds , algae , diatoms , fish scales and , incidentally , sand ( bishai & abu gideiri , 1965a ; bishai & abu gideiri , 1965b ; winemiller & kelso - winemiller , 1996 ; sanyanga , 1998 ) . from observations of stomach contents , the diet of most mochokids is probably very similar ; that is , they are omnivores . for some of the larger sucker - mouthed species ( i . e . , atopochilus and euchilichthys ) the stomach contents contain a high proportion of silt , algae and detritus . for these taxa it seems likely that scraping or grazing is the predominant method of feeding .
in addition to being numerous and widespread on the african continent , the mochokidae are actually quite diverse in terms of morphology . mochokids are small to medium sized catfishes , ranging from less than 40 mm sl as an adult in certain species of chiloglanis and microsynodontis , up to a reported 800 mm sl in some species of synodontis . most of the larger species are in the genus synodontis ; still , the majority of those are less than 300 mm sl . the morphology of mochokids is notably diverse aside from size as well ; the size and shape of the mouth and the shape of the body are notable examples . most mochokids exhibit a ventrally directed mouth , with papillose lips and , more often than not , branched mandibular barbels ( e . g . , most synodontis ) . species exhibiting this type of mouth are quite often deep bodied and somewhat triangular in lateral view , their greatest depth being at the base of the dorsal spine . yet others with this same type of mouth tend to be more cylindrical along their entire length ( microsynodontis and few synodontis ) . species of chiloglanis , atopodontus , atopochilus and euchilichthys exhibit a ventrally directed mouth , but it is formed as a sucker - like oral disc , wherein the lower lip is greatly expanded and incorporates the mandibular barbels . here , the body shape tends to be quite cylindrical or depressed and the head is quite often greatly depressed . some mochokids do not possess a ventrally directed mouth . mochokiella paynei , acanthocleithron chapini and members of the genus mochokus have mouths that are only slightly subterminal ; while the mandibular barbels are still branched , the lips are not nearly as fleshy . here , again , the body shape tends to be relatively cylindrical .
figure 2 : photomicrographs showing changes in testes of synodontis schall ( a & b ) transverse section of the immature and maturing testes showing spermatogonia ( sp ) and clusters of primary and secondary spermatocytes ( ps & ss ) with a few spermatids ( s ) . ( c & d ) ripe and spawning testes showing active spermatogenesis . sperm ducts distended with spermatozoa ( sz ) . mag . x400 in a , b , d & d .
the mochokidae are a family of african catfishes known commonly as ‘squeakers’ and ‘upside - down catfishes . ’ these common names refer to some unusual habits of certain members of the large genus synodontis . the name squeaker refers to the fact that , when agitated , many species in the genus are capable of making a squeaking noise by stridulation of the pectoral spine against the pectoral girdle ( jubb , 1967 ) ; stridulation is also apparent in mochokiella paynei and some species of atopochilus .
results from this investigation , showed that fecundity - body weight and fecundity - ovary weight logarithmic relationships were more highly correlated and significant than the fecundity - total length relationship . similar observation was reported by araoye for s . schall [ 10 ] , but halim and guma ' a noted a high correlation between fecundity and body length for same species from the white nile near khartoum [ 9 ] . the positive correlation between fecundity - body weight and fecundity - ovary weight may be attributed to the high fecundity characteristic of members of the genus synodontis [ 10 ] .
the fecundity of 81 ripe females of synodontis schall from jamieson river ranged from 1530 - 13 , 965 eggs with a mean of 6080 eggs . the total lengths of these ripe specimens range from 19 . 40cm to 26 . 20cm with body weights of 73 . 62gm to 252 . 15gm and ovary weights of 2 . 30gm to 28 . 41gm . maximum fecundity was recorded from a fish measuring 21 . 70gm in total length and 138 . 69gm in body weight and the minimum , from a fish measuring 24 . 80gm in total length and 131 . 71gm in body weight .
figure 3 : photomicrographs showing changes in the ovary of synodontis schall . ( a & b ) transverse section of immature and recovery ovaries showing oogonia ( o ) ( c ) the maturing ovary with primary vitellogenic oocyte ( pvo ) , showing increase in size and accumulation of yolk granules ( yg ) droplets . ( d ) the ripe ovary with secondary vitellogenic oocytes ( svo ) and post - vitellogenic oocytes ( psvo ) . ( e ) the spawning ovary with hyaline post vitellogenic oocytes ( psvo ) ready for spawning . mag x100 in a , d & e ; x160 in b and x200 in c .
monthly samples of synodontis schall were collected from four locations in the river from october 2010 and october 2011 . the fish samples were obtained from hired fishermen who carried out fishing between 0730 - 1200h during the day and 0200 - 0400h in the night . the principal gears employed in all the sampling zones were cast nets ( 35 - 55 mm stretched mesh size ) and gill nets ( 20 - 70 mm stretched mesh size ) . fish samples caught were transported in an ice box from the fishing site to the laboratory . routine measurements of length ( standard and total ) were taken to the nearest 0 . 1 cm and specimens were weighed to the nearest 0 . 1 g .
all species in the genus synodontis have a hardened head cap that has attached a process ( humeral process ) which is situated behind the gill opening and pointed towards the posterior . the dorsal fin and pectoral fins have a hardened first ray which is serrated . caudal fin is always forked . there is one pair of maxillary barbels , sometimes having membranes and occasionally branched . the two pairs of mandibular barbels are often branched and can have nodes attached . the cone - shaped teeth in the upper jaw are short . s - shaped and movable in the lower jaw . these fish produce audible sounds when disturbed rubbing the base of the pectoral spine against the pectoral girdle . a nondescript but fairly common import .
pigmentation and patterning of mochokid skin is also diverse . mochokids are popular in the pet trade because they have showy colors , sharply contrasting patterns like stripes and polka - dots and , quite often , extravagant fins . as some of the largest and most active mochokids , species of synodontis display an amazing array of patterns and pigmentation that may , in some cases , serve as visual cues to conspecifics . it might also be true that the bright , contrasting coloration found in some species serves as a warning to predators . like many catfishes , some mochokids possess specialized poison glands for delivering offensive chemicals along with a ‘stick’ by the pectoral spine ; anecdotal accounts indicate that these wounds can be very painful . however , field studies that might demonstrate function of these varied patterns have not been done .
all species in the genus synodontis have a hardened head cap that has attached a process ( humeral process ) which is situated behind the gill opening and pointed towards the posterior . the dorsal fin and pectoral fins have a hardened first ray which is serrated . caudal fin is always forked . there is one pair of maxillary barbels , sometimes having membranes and occasionally branched . the two pairs of mandibular barbels are often branched and can have nodes attached . the cone - shaped teeth in the upper jaw are short . s - shaped and movable in the lower jaw . these fish produce audible sounds when disturbed rubbing the base of the pectoral spine against the pectoral girdle . juvenile colouration is quite different from that of the adult . the change begins when the fish reach about 40mm and gradually continues until they pass the 100mm mark .
many mochokid species exhibit obvious sexual dimorphism . for example , many species in the genus chiloglanis show dimorphism of the caudal and anal fins ( roberts , 1989 ; seegers , 1996 ; friel & vigliotta , 2006 ) ; some chiloglanis also display sexual dimorphism of the cleithral process , wherein males possess a greatly enlarged process shielding the flank . in the closely related genus atopochilus , sexual dimorphism of the anal fin is sometimes evident . some mochokids exhibit spiny ornamentation of the skull roof bones , opercular series and pectoral girdle ( friel & vigliotta , 2006 ) . in the case of synodontis acanthoperca , a spine found at the rear of the opercle is , itself , sexually dimorphic . the spines of males are much larger than those of females . this is also true for mochokiella paynei ( personal observation ) , which was previously unknown to possess opercular spines or exhibit sexual dimorphism .
in the juvenile stage , the ovary consists of very small spherical oogonia and a few primary oocytes , constituting the first growth phase or previtellogenesis . the recovery and maturing stages constitute the second growth phase or vitellogenesis ; which is characterised by rapid growth . during this period oocytes increase rapidly in size due to accumulation of yolk materials in the oocytes cytoplasm . next is the ripe and spawning stages which consist mainly of secondary vitellogenic and post - vitellogenic oocytes . this is the period of oocyte maturation , when oocytes had accumulated enough yolk , become matured and ripe and ready for ovulation and spawning . similar observations were reported for synodontis schall from asa lake , ilorin [ 10 ] , african lungfish ( protopterus annectens ) from river niger [ 21 ] and tilapia mariae and chromidotilapia guentheri from jamieson river [ 22 , 23 ] . however , araoye , who worked on same species as in the present study , only examined the morphological features of the gonads [ 10 ] . the use of histological descriptions is important in clearly separating the different maturity stages and enables one to access correctly the level of reproductive activity ( fertility ) of a measured fish specimen .
absolute fecundity of s . schall ranged from 1530 to 13 , 965 eggs with a mean of 6080 eggs . the estimate of fecundity in the present study was much lower than the estimates reported for same species ( 10 , 000 - 90 , 000 eggs ) [ 9 ] and ( 7910 to 64 , 450 eggs ) [ 10 ] . although , the ovary weights of the specimens ( 6 . 30 - 43 . 75g ) from asa lake were observed to be larger in size than those of the present study ( 2 . 30 - 28 . 41gm ) . however , similar fecundity estimates were reported for s . batensoda ( 6850 - 20 , 400 eggs ) and s . nigrita ( 952 - 11 , 400 eggs ) from lake kainji [ 26 ] . the change in fecundity estimation could be due to different environmental conditions in which these different populations live . in general , compared to most freshwater fishes , willoughby , noted that members of - the genus synodontis have always exhibited high fecundity and this can be attributed to the small size of their eggs [ 26 ] . according to olatunde , high fecundity is an advantage because of the continued existence of fish which depends on the number of eggs hatched and their survival to adult stage [ 4 ] .
400mm or 15 . 7
sl . find near , nearer or same sized spp .
first lay the fish in your hand with its head toward your palm and the tail toward your fingers . hold the dorsal spine between your middle and ring finger so the fish is belly up and you won ' t get stuck ( which by the way , hurts like crazy ! ) . the genital pore is in a small furrow of tissue ( in healthy fish ) and will be obstructed by the pelvic fins . pull down on the tail gently to arch the fishes spine and the pelvic fins will stand and the furrow open to display the genital pore and the anus of the fish . the male has a somewhat ridged genital papillae on which the spermatoduct is on the back side , facing the tail fin . a gravid female will also show an extended papillae but the oviduct is on the ventral side of the papillae ( and may also show a little redness if really gravid ) . a thin or emaciated female will have just two pink pores , the oviduct and the anus .
africa : niger and ouémé rivers , nokoue lake . also known from the bénoué .
sinking catfish pellets are taken , frozen foods such as bloodworm and brineshrimp are eagerly devoured , will also take algae wafers and most other commercially prepared foods .
a sandy substrate is best but a smooth rounded gravel will suffice . prefers wood to stone . must have its own hideaway in the form of a cave or pipe .
more suited to the larger community . as with many other catfish species it will eat what it can fit into its mouth so no small tetras .
does well with larger barbs ( such as tinfoil and lemon barbs ) . will tolerate other catfish so long as they are no competition . a good fish for the larger cichlid aquarium .
catalogue of the fresh - water fishes of africa v . 2 - pp403 - fig . 305
( 1 ) synodont _ fan , ( 2 ) mrfishydude , ( 3 ) arapaimag , ( 4 ) mcjlance , ( 5 ) n0body of the goat , who also notes :
very stocky ~ 15cm sl catfish , very outgoing and diurnal for a syno ,
troy
is often one of the first to greet me when looking into the 6 - foot african tank .
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mochokid catfishes are currently restricted to the freshwaters of africa , but are nearly ubiquitous in the habitable waters of the continent . a high degree of morphological diversity allows mochokid catfishes to inhabit some of the fastest flowing streams and cataracts to the widest and deepest stretches of the congo river . mochokids also inhabit the massive african rift lakes like tanganyika , victoria and nyasa . the greatest diversity of mochokids almost certainly occurs in the congo river and its numerous tributaries , but they are also found in many of the rivers and lakes of western africa , southern africa , eastern africa and in the nile . like a handful of other catfishes , some mochokids are known to swim in mid - water ; other members of the family are primarily benthic . likewise , some mochokids shoal while others are rather solitary . as a rule they are most active during the night , but they can be found hiding amongst plants , logs and other submerged structure during the day .
lateral view of atopochilus vogti , illustrating typical body shape in sucker - mouthed mochokids ; cu 93752 . ©
vigliotta ( 2008 ) provides several synapomorphies as diagnostic features for the mochokidae including : absense of the ascending process of meckel’s cartilage ; a shortened horizontal process of meckel’s cartilage ; coronomeckalian extremely reduced or even absent ; absence of a coronoid process ; absence of an interhyal ; presence of a pectoral locking foramen ( absence / reversal in most suckermouthed species ) ; seven pelvic - fin rays ; fusion of upper caudal - fin elements ( absence / reversal in atopochilus and euchilichthys ) ; a reduced number of mandibular sensory canal pores ( 3 or fewer ) ; and distinctive , ramified inner and outer mandibular barbels ( absence / reversal in suckermouthed mochokids where these barbels are partially or completely incorporated into an expanded lower lip ) .
1a . lips and barbels modified into oral disc ( fig . 27c ) ; postcleithral process short ( fig . 22c ) ; 5 infraorbitals ( figs . 2c , 4b ) ; pelvic - fin origin at vertical at end of dorsal - fin base . . . 2
1b . lips and barbels not modified into oral disc ; postcleithral process quite long ( fig . 22b ) ; 4 infraorbitals figs . 2b , 4a ) ; pelvic - fin origin beyond end of dorsal - fin base . . . 5
2a . mandibular teeth bunched ( in bouquet ) at midline ( fig . 3d in friel and vigliotta , 2008 ) in or spread across mouth opening in one or two discrete rows ( fig . 3e–f in friel and vigliotta , 2008 ) ; eyes without free orbital margin ; mandibular sensory - canal absent ; 4 to 6 dorsalfin rays ( typically 5 ) ; 5 to 7 branchiostegal rays ( typically 5 or 6 ) … chiloglanis
2b . mandibular teeth spread across mouth opening in more than two discrete rows ( fig . 3a–c in friel and vigliotta , 2008 ) ; eyes with free orbital margin ; mandibular sensory canal present , with 2 pores on each side ; 6 to 7 dorsal - fin rays ; 7 to 8 branchiostegal rays . . . 3
3a . small anteriorly directed pocket underneath lower lip produced by folds of skin ( fig . 4a in friel and vigliotta , 2008 ) ; width of mandibular tooth rows less than 66 % width of paired premaxillae ( fig . 3a in friel and vigliotta , 2008 ) ; caudal fin emarginate ; gas bladder extremely reduced to two small bulbs ( fig . 5 ) … atopodontus
3b . small anteriorly directed pocket underneath lower lip absent ( fig . 4b in friel and vigliotta , 2008 ) ; width of mandibular tooth rows more than 66 % width of paired premaxillae ( fig . 3b–c in friel and vigliotta , 2008 ) ; caudal fin forked ; gas bladder only modestly reduced ( fig . 3c ) . . . 4
4a . mandibular teeth spatulate and unicuspid ( fig . 10c ) ; large posterior pectoral - spine serrae ; one or only a few pores at sites along the cephalic sensory canals ; fewer than 40 vertebrae … atopochilus
4b . mandibular teeth with lengthwise keel creating trowel shape and sometimes bicuspid from wear ( fig . 10a ) ; small posterior pectoral - spine serrae ; several pores at various sites along the cephalic sensory canals ; more than 40 vertebrae … euchilichthys
5a . s - shaped auxiliary dentary teeth present ( fig . 10a , c–f ) ; premaxillary teeth differentiated by shape and size front to back ; lips plicate ( with folds at corners of mouth ) . . . 6
5b . s - shaped auxiliary dentary teeth absent ( fig . 10b ) ; premaxillary teeth showing little , if any , differentiation from front to back ; lips papillose , but not plicate ( without folds ) . . . 7
6b . eyes without free orbital margin ; 12 to 14 principal caudal - fin rays ; tail truncate or rounded ; 6 or 7 pectoral - fin rays ( typically 6 ) ; lateral mandibular barbels with single , gracile branches at each point along length ( fig . 27a ) … microsynodontis
7a . dorsal surface of the head and nuchal shield covered by large ridges and spinous projections ; cleithrum bearing spine in males ; rounded , blunt postcleithral process ; anus and urogenital opening distant ; free orbital margin present ; gill openings open to isthmus ; tips of mandibular teeth spatulate ; medial mandibular barbels with multiple , thick branches at each point along length ( fig . 27b ) ; 8 to 9 pectoral - fin rays ; 17 caudal - fin rays ; more than 40 vertebrae … acanthocliethron
7b . dorsal surface of the head and nuchal shield without ridges and spinous projections ; cleithrum without spine in males ; pointed postcleithral process ; anus and urogenital opening very close ; free orbital margin absent ; gill openings restricted to sides of the head ; tips of mandibular teeth pointed ; medial mandibular barbels with single , gracile branches at each point along length ( fig . 27a ) ; 5 to 7 pectoral - fin rays ; 13 or 15 caudal - fin rays ; fewer than 36 vertebrae . . . 8
chapman , l . j . , l . kaufman , and c . a . chapman . 1994 . why swim upside - down - a comparative study of 2 mochokid catfishes . copeia 1994 : 130135 .
ferraris , c . j . , jr . 2007 . checklist of catfishes , recent and fossil ( osteichthyes : siluriformes ) , and catalogue of siluriform primary types . zootaxa 1418 : 1628 .
friel , j . p . and t . r . vigliotta . 2008 . atopodontus adriaensi , a new genus and species of african suckermouth catfish from the ogôoué and nyanga river systems of gabon ( siluriformes mochokidae ) . proceedings of the academy of natural sciences of philadelphia 157 : 1323 .
jubb , r . a . 1967 . freshwater fishes of southern africa . cape town , amsterdam , balkema , 248 pp .
ng , h . h . and r . m . bailey . 2006 . chiloglanis productus , a new species of suckermouth catfish ( siluriformes : mochokidae ) from zambia . occasional papers of the university of michigan museum of zoology 738 : 113 .
otero , o . and m . gayet . 2001 . palaeoichthyofaunas from the lower oligocene and miocene of the arabian plate : palaeoecological and palaeobiogeographical implications . palaeogeography palaeoclimatology palaeoecology 165 : 141169 .
roberts , t . r . 1989 . systematic revision and description of new species of suckermouth catfishes ( chiloglanis , mochokidae ) from cameroun . proceedings of the california academy of sciences series 4 , 46 : 151178 .
sato , t . 1986 . a brood parasitic catfish of mouthbrooding cichlid fishes in lake tanganyika . nature 323 : 5859 .
seegers , l . 1996 . the fishes of the lake rukwa drainage . musée royal de lafrique centrale , annales , sciences zoologiques 278 : 1407 .
seegers , l . 2008 . the catfishes of africa . a handbook for identification and maintenance . aqualog verlag , rodgau , germany . 604 pp .
stewart , k . m . 2001 . the freshwater fish of neogene africa ( miocene - pleistocene ) : systematics and biogeography . fish and fisheries ( oxford ) 2 : 177230
vigliotta , t . r . 2008 . a phylogenetic study of the african catfish family mochokidae ( osteichthyes , ostariophysi , siluriformes ) , with a key to genera . proceedings of the academy of natural sciences of philadelphia 157 : 73136 .
winemiller , k . o . , and l . c . kelso - winemiller . 1996 . comparative ecology of catfishes of the upper zambezi river floodplain . journal of fish biology 49 : 10431061 .
wisenden , b . d . 1999 . alloparental care in fishes . reviews in fish biology and fisheries 9 : 4570 .
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. african squeaker and suckermouth catfishes . version 02 march 2009 ( under construction ) .
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entsua - mensah , m . , darwall , w . & smith , k .
this species is found in the niger basin , including the benue . the specimens reported from the ouémé by poll ( 1971 ) belong to s . melanopterus .
this is a benthopelagic species of 39 . 7 cm tl . recorded size at maturity is 20 . 1 cm tl for female and 22 . 4 cm tl for male in kainji lake in nigeria .
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greek , syn , symphysis = grown together + greek , odous = teeth ( ref . 45335 )
freshwater ; benthopelagic ; ph range : 6 . 2 - 7 . 2 ; dh range : 6 - 20 . tropical ; 22°c - 27°c ( ref . 12468 ) ; 10°n - 4°n
africa : endemic to the niger river basin , including the benue ( ref . 57223 ) . report from the ouémé ( benin ) ( ref . 3202 ) refers to misidentified s . melanopterus specimens ( see dvd version of ref . 57223 ) . report from the chari - logone ( chad basin ) in central african republic ( see map in ref . 57223 ) questionable .
maturity : l m ? , range 20 - ? cm max length : 40 . 0 cm sl male / unsexed ; ( ref . 31256 )
dorsal spines ( total ) : 1 ; anal spines : 0 . diagnosis : gill slits not extending ventrally beyond pectoral - fin insertions ; maxillary barbels distinctly fringed , longer than head , unbranched and lacking tubercles , but with a broad , long and dark basal membrane ; outer mandibular barbels with few simple , short ramifications , inner mandibular barbels with tuberculate , subdivided branches ; mandibular teeth moderately developed , numbering 45 - 64 ( 64 in the holotype ) ; denticulations on pectoral - fin spines weaker on outer than on inner margin ; dorsal - fin spine smooth anteriorly ; first ray of dorsal and pectoral fins , as well as both caudal - fin lobes extended into filaments ; humeral process pointed , granulose , its ventral margin keeled and bearing 3 backward - pointing spines ( sometimes only 1 or 2 in young individuals ) ; adipose fin normally developed and distinctly separated from rayed dorsal fin ( ref . 57223 ) . coloration : ground colour uniformly greenish - yellow ; series of black spots sometimes present on fins in young individuals ( ref . 57223 ) .
oviparous ( ref . 205 ) . maximum size 395mm tl , 297mm sl ( ref . 57223 ) .
oviparous ( ref . 205 ) . distinct pairing during breeding ( ref . 205 ) .
paugy , d . and t . r . roberts , 2003 . mochokidae . p . 195 - 268 in c . lévêque , d . paugy and g . g . teugels ( eds . ) faune des poissons d ' eaux douce et saumâtres de l ' afrique de l ' ouest , tome 2 . coll . faune et flore tropicales 40 . musée royal de l ' afrique centrale , tervuren , belgique , museum national d ' histoire naturalle , paris , france and institut de recherche pour le développement , paris , france . 815 p . ( ref . 57223 )
phylogenetic diversity index ( ref . 82805 ) : pd 50 = 0 . 5000 [ uniqueness , from 0 . 5 = low to 2 . 0 = high ] .
bayesian length - weight : a = 0 . 00617 ( 0 . 00259 - 0 . 01467 ) , b = 3 . 09 ( 2 . 88 - 3 . 30 ) , in cm total length , based on lwr estimates for this ( sub ) family - body shape ( ref . 93245 ) .
trophic level ( ref . 69278 ) : 2 . 8 ±0 . 3 se ; based on size and trophs of closest relatives
resilience ( ref . 69278 ) : medium , minimum population doubling time 1 . 4 - 4 . 4 years ( k = 0 . 3 ) .
vulnerability ( ref . 59153 ) : moderate vulnerability ( 35 of 100 ) .
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to cite this page : myers , p . , r . espinosa , c . s . parr , t . jones , g . s . hammond , and t . a . dewey . 2018 . the animal diversity web ( online ) . accessed at https : / / animaldiversity . org .
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oviparous ( ref . 205 ) . maximum size 395mm tl , 297mm sl ( ref . 57223 ) .
africa : endemic to the niger river basin , including the benue ( ref . 57223 )
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boulenger , george a . 1911 . catalogue of the fresh - water fishes of africa in the british museum ( natural history ) . , london . vol . 2 : i - xii , 1 - 529 .
anonymous ( 1998 ) fisheries statistical bulletin , kainji lake , northern nigeria , 1997 . : nigerian - german kainji lake fisheries promotion project technical report series 9 . 29pp .
baensch , h . a . and r . riehl ( 1995 ) aquarien atlas . band 4 . : mergus verlag gmbh , verlag für natur - und heimtierkunde , melle , germany . 864 p .
chinese academy of fishery sciences ( 2003 ) chinese aquatic germplasm resources database . : urltoken
gosse , j . - p . ( 1986 ) mochokidae . : p . 105 - 152 . in j . daget , j . - p . gosse and d . f . e . thys van den audenaerde ( eds . ) check - list of the freshwater fishes of africa ( cloffa ) . isnb , brussels , mrac , tervuren ; and orstom , paris . vol . 2 .
olaosebikan , b . d . and a . raji ( 1998 ) field guide to nigerian freshwater fishes . : federal college of freshwater fisheries technology , new bussa , nigeria . 106 p .
varjo , m . , l . koli and h . dahlström ( 2004 ) kalannimiluettelo ( versio 10 / 03 ) . : suomen biologian seura vanamo ry .
wu , h . l . , k . - t . shao and c . f . lai ( eds . ) ( 1999 ) latin - chinese dictionary of fishes names . : the sueichan press , taiwan . 1028 p .
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department of animal and environmental biology faculty of life sciences , university of benin , benin city , nigeria .
biological studies of s . schall have been reported [ 1 , 4 , 5 , 6 , 7 , 8 ] . however , only few reports exist on the aspects of its reproduction . the morphology of the gonads in the reproductive cycle of s . schall from asa lake , ilorin nigeria has been studied [ 9 , 10 ] . reproductive biology is an important branch of fishery science and it is useful in fish culture and management . the ultimate aim of fisheries management is to attain sustainable exploitation of fisheries resources and this requires a proper understanding of the population dynamics of the fish stock . reproductive biology is one of the major factors influencing the dynamics of a given population .
the present study was therefore undertaken with a view to contributing to the reproductive biology of s . schall in nigeria , with emphasis on the histology of its gonads which clearly assist in separating the different stages of gonadal development .
the study was carried out in the jamieson river ( 5°41’ - 5°58’e ; 5°54’ - 6°08’n ) , one of the two confluent tributaries of benin river ( fig . 1 ) . it takes its origin from ugboko - niro and flows in a south - westerly direction , 70 km , to sapele , where it empties into the benin river , which discharges into the atlantic ocean at the bight of benin .
figure 1 : map of study area ( a ) south - west coastal zone of nigeria showing the location of river jamieson ( b ) the course of river jamieson showing the sampling zones .
jamieson river lies in an area with a tropical rainforest climate . two main seasons prevail ; the wet ( may to october ) and dry season from november to april the following year . the river flows all year round with the highest level and discharges during the flood period ( july - november ) . the river is subjected to tidal inundation from the benin river at the sapele - sakponba stretch . the fringing plants consists mainly of cyrtosperma senegalense ( schott ) egnl . , lonchocarpus griffonianus dunn , anthocleista vogelii planch , pandanus candelabrum p . beauv and crinum jagus thomps .
the fish samples were dissected , sexed and the state of the gonads were recorded [ 11 ] . ovaries and testes were detached and weighed to the nearest 0 . 01g . the data on the body and gonad weights were used to compute the gonadosomatic index ( gsi ) [ 12 ] .
immature ovaries and all stages of testes were fixed in bouin’s fluid . for specimens with maturing to mature ovaries , one of the ovaries was fixed in bouin’s fluid and the other in gilson’s fluid . all gonads fixed in bouin’s fluid were later processed , embedded in paraffin , sectioned at 4 - 6μm , stained with haematoxylin and eosin and used for histological evaluation [ 13 ] .
ovaries preserved in gilson’s fluid , had their eggs separated from the ovarian tissues by frequent vigorous agitation of the specimen bottles after a week . the eggs were then cleaned thoroughly by rinsing with the fixative three to four times and the number of eggs in each pair of ovaries was determined by direct enumeration . size frequency distribution of intraovarian oocytes was determined by measuring the diameter of one hundred oocytes taken at random from anterior , middle and posterior region of five ripe female specimens [ 14 ] . the egg diameters were measured with a calibrated micrometer mounted in the eye - piece of a binocular microscope [ 15 ] .