the cuckoo-finch ( anomalospiza imberbis ) , also known as the parasitic weaver or cuckoo weaver , is a small passerine bird now placed in the family viduidae with the indigobirds and whydahs .

it occurs in grassland in africa south of the sahara .

the male is mainly yellow and green while the female is buff with dark streaks .

the eggs are laid in the nests of other birds .

cuckoo - finch

the preferred habitats for cuckoo finch are : woodlands and grasslands . the cuckoo finch is also at home in wetland and bushveld areas .
the cuckoo finch is a southern african bird that belongs to the viduidae bird family group which includes birds such as whydahs , indigobirds , cuckoo finch .
cuckoo finch ( anomalospiza imberbis fam . viduidae ) kruger park birds & birding .
in terms of distribution of the cuckoo finch in the kruger national park you may not see it in all areas . cuckoo finch : see above distribution map .
the cuckoo finch takes on more than a single mate ( it is bigamous ) .
this outraged tawny - flanked prinia has just seen a cuckoo finch near its nest .
a cuckoo finch chick about to fledge from the nest of a red - faced cisticola .
cuckoo - finch ( anomalospiza imberbis ) is a species of bird in the viduidae family .
rusty - breasted cuckoo , cacomantis sepulcralis , is split from brush cuckoo , cacomantis variolosus .
female cuckoo finch and female southern red bishop . but which is which ? claire spottiswoode , author provided
image : cuckoo finch chick sitting in the nest of its foster parents . courtesy of claire spottiswoode .
the cuckoo finch is mainly found in light and densely wooded forests , where there are mopane trees .
you will not see cuckoo finch in flocks . the bird prefers to act singly or in pairs .
museum specimens indicate historical distributions . the map below shows locations from which museum specimens of cuckoo - finch were collected . you can see more information on the individual museum specimens of cuckoo - finch here .
cuckoo finch , midmar game reserve , kwazulu - natal , south africa . [ photo alan manson © ]
the cuckoo finch ( latin name anomalospiza imberbis ) is described in roberts birds of southern africa , 7th edition . this bird has a unique roberts number of 820 and you will find a full description of this bird on page 1081 also a picture of the cuckoo finch on page 1009 . the cuckoo finch belongs to the family of birds classified as viduidae . according to the percy fitzpatrick institute of african ornithology the cuckoo finch is also known by these other names : parasitic weaver , cuckoo weaver .
a cuckoo finch in sheep ' s clothing : cuckoo finches in africa have adopted a unique disguise to help them lay their eggs in other birds ' nests .
the cuckoo finch is neither endemic or near endemic to the kruger national park . it is however a rare summer resident
) . he identified the young as that of a cuckoo finch only after roberts had photographed young cuckoo finches in nests of prinias and cisticolas . chicks thought to have been of
the female cuckoo finch ( l ) has evolved to be nearly identical to the harmless female red bishop ( r ) .
they reject foreign eggs from their nest at a higher rate after they have seen either a female cuckoo finch or a female bishop .
the outside circle shows eggs laid by tawny - flanked prinia females , and the inside circle shows eggs laid by different cuckoo finch females .
moluccan cuckoo , cacomantis heinrichi , is split from brush cuckoo , cacomantis variolosus . [ cuculidae , pelecanae i , 2 . 13 ]
some of the different types of patterns found in cuckoo finch eggs , which mimic african tawny - flanked prinia eggs . courtesy of claire spottiswoode .
the outside circle shows eggs laid by tawny - flanked prinia females , and the inside circle shows eggs laid by different cuckoo finch females . claire spottiswoode
a three day old cuckoo finch chick ( left ) with a tawny - flanked prinia hatchling ( right ) which is about to die of starvation .
the cuckoo - finch has a scattered distribution across sub - saharan africa where it occurs in open or lightly wooded grassland , especially near damp areas .
so were the prinia really deceived by the cuckoo finches’ mimetic plumage ? to answer this , we carried out one last experiment . we presented a female cuckoo finch , a female southern red bishop or a male southern red bishop model near a prinia nest . after that , we replaced a prinia egg with an experimental egg to simulate egg laying by a real cuckoo finch .
to answer this question , first we measured and compared the colour and pattern of cuckoo finches’ plumage to those of vidua finches ( the cuckoo finch’s closest relatives ) and weavers at the natural history museum at tring , uk .
as mentioned in the above paragraphs , cuckoo finches lay in the nests of prinias and cisticolas in grassland and marshes and in savanna and open woodland . these hosts rear the young cuckoo finch , usually the only chick in the brood that fledges . this is because the cuckoo finch , when she lays her egg , removes the host ' s eggs , thereby leaving her own young brood parasite as the only chick in the nest . occasionally , a host lays after the cuckoo finch has done so , and it may then rear its own young along with the parasitic nestling . sometimes , more than one cuckoo finch egg is deposited in the nest and two chicks survive and fledge . the survival of more than one chick , including either a host chick or another brood - parasitic one , indicates that the young cuckoo finch does not evict its nestmates .
so were the prinia really deceived by the cuckoo finches & apos ; mimetic plumage ? to answer this , we carried out one last experiment . we presented a female cuckoo finch , a female southern red bishop or a male southern red bishop model near a prinia nest . after that , we replaced a prinia egg with an experimental egg to simulate egg laying by a real cuckoo finch .
our work shows that the cuckoo finch has evolved another novel strategy of attack , whereby it defeats both sensory and cognitive components of host rejection behaviour .
the treatment of darwin ' s finches has been updated . the warbler finch , certhidea olivacea , has been split into green warbler finch , certhidea olivacea , and gray warbler finch , certhidea fusca . [ thraupidae , thraupid group , 2 . 12 ]
to answer this question , first we measured and compared the colour and pattern of cuckoo finches & apos ; plumage to those of vidua finches ( the cuckoo finch’s closest relatives ) and weavers at the natural history museum at tring , uk .
this diversity of mimicry has evolved because hosts fight back , since they pay a high price if they are tricked by a cuckoo finch . the young finch usually hatches a day or two in advance of the host chicks , which typically only survive a day or two before starving to death , while the cuckoo finch obtain ' s the lion ' s share of the food the host parents bring to the nest .
cuckoo finch eggs ( right column ) mimic their eggs of their hosts ( left column ) . the top two rows of eggs are from red - faced cisticola nests and the bottom four rows are from tawny - flanked prinia nests . tawny - flanked prinias lay a range of egg colours and patterns to foil cuckoo finch mimicry .
it would be great to know whether other parasites have a similar strategy to the cuckoo finch , and whether there is any way hosts can fight back .
cuckoo finches change their appearance with the season as a result of feather abrasion .
african tawny - flanked prinias are the targets of cuckoo finches in southern zambia .
having highly variable eggs among individuals makes it hard for each female cuckoo finch to match many of the egg types that different prinias lay ,
explained dr stevens .
the description for the cuckoo finch ( latin name anomalospiza imberbis ) can be found in the 7th edition of the roberts birds of southern africa . the anomalospiza imberbis can be quickly identified by its unique roberts identification number of 820 and the detailed description of this bird is on page 1081 . you will find a picture of the cuckoo finch on page 1009 .
this is unfortunate for the cuckoo finch – and we suspect this is because the rate of parasitism is consistently high at this site , making this strategy worthwhile for the crafty prinias .
the film clip shows a nest of the most frequent host of the cuckoo finch , the tawny - flanked prinia , which has an extravagantly diverse range of eggs . the prinia parent has recognised that an egg in its nest is that of a cuckoo finch , and proceeds to eject it by spearing it on the end of its beak and carrying it away .
the researchers took 999 randomly chosen pairs of 300 prinia and 84 cuckoo finch eggs in their study population , plugged them into the model and simulated egg rejection using different host - to - parasite egg ratios . they saw that the cuckoo finch eggs are less likely to be ejected when they comprise a greater proportion of the nest , especially if the mimicry is good .
cuckoo finch eggs mimic those of their hosts , and the same cuckoo finch female commonly lays two or more eggs in the same host nest . in this paper we show that this increases her chances of tricking hosts into accepting the parasitic eggs as their own . by increasing the proportion of foreign eggs in the clutch , cuckoo finches appear to be able to take advantage of uncertainty in the sensory and cognitive processes that hosts use to distinguish foreign eggs from their own .
the cuckoo finch was discovered to be a brood parasite after v . g . l . van someren , in 1912 , photographed and collected a young bird in the nest of a rattling cisticola (
the nesting habit of cuckoo finch is to use the nest of another bird . the surrogate family then raise the chicks . the bird lays eggs which are white in colour and number between 1 to 3
using model cuckoo finches and model southern red bishops ( a common weaver species at the study site ) , we tested whether the prinias reacted differently towards female cuckoo finches and female southern red bishops , compared to male cuckoo finches and male southern red bishops . unlike females , males of these two species look very different : male cuckoo finches are bright yellow and male southern red bishops are black and red .
left : two prinia eggs and one cuckoo egg ( good mimicry ) . right : one cuckoo egg and two prinia eggs ( poor mimicry ) . courtesy of stevens et al . / nature communications .
the name cuckoo is common to many parasitic bird species that rely upon others to raise their young .
the cuckoo finch does not built its own nest but rather invades the nest of other birds . if the bird does not find an empty nest it will attack the host ( original nest owner ) and displace it
the cuckoo finch in zambia has evolved to be almost indistinguishable from common and harmless female weaver birds , such as the southern red bishop , said dr william feeney , from the australian national university ( anu ) .
we tested these predictions in the tawny - flanked prinia and its parasite , the cuckoo finch . egg appearance ( colour and pattern ) varies greatly among individuals in both host and parasite , but individual females always lay a single egg - type throughout their lives 7 , 8 . cuckoo finches do not target prinia clutches that resemble their own eggs but instead rely on chance matches to succeed 7 . therefore , mimicry can range from very good to poor . a cuckoo finch female commonly lays two eggs in the same host nest 22 ( see below ) .
the cuckoo finch looks a lot more similar to the bishop than its nearest relatives , the vidua finches , suggesting that it has evolved to be able to hang around prinia nests without arousing suspicion ,
he said .
the cuckoo finch , the whydahs and the indigobirds are brood parasites , laying their eggs in the nests of other kinds of songird . the nesting birds , the hosts , rear the young brood parasites along with their own brood .
what is interesting about this situation is that each female cuckoo finch only lays a particular type of egg mimicking a particular host species , and will specialise only on that species , so that within a small area , neighbouring cuckoo finches may look and sound the same , but have hatched from different host nests and lay eggs that mimic that host species . for example , the eggs in the header image above are all cuckoo finch eggs from an area of less than a thousand hectares on our study site in zambia , and come from the nests of three different host species .
unlike the indigobirds and whydahs , which have since split up into numerous species each specialising on a single host species , the cuckoo finch has remained one species comprising several host - specific races . for instance , the cuckoo finches we study in zambia lay their eggs in the nests of the tawny - flanked prinia prinia subflava and at least three cisticola species .
one of the first indicators to take note of when trying to identify a bird is it relative size . for example how big is the bird compared to a well known familiar bird . the cuckoo finch is a small bird about the size of a house sparrow . do not take this relative indicator as anything other than a rough easy to remember indicator . it is not a accurate visualization . the height of the cuckoo finch is about 13 cms and its weight is about 20 gms
researchers found that the cuckoo finches repeatedly targeted the same nests to improve the probability of their eggs being cared for .
the cuckoo - finch typically occurs in pairs or small flocks during the breeding season and larger flocks outside the breeding season . it forages on the ground or perched on the flower heads of grasses or herbs . it feeds mainly on grass seeds .
. female long - tailed paradise - whydahs are attracted to songs of their host , the melba finch , and not to orange - winged pytilia songs ; in aviaries , they sometimes lay when they hear songs of the melba finch . males of this paradise - whydah mimic songs of the melba finch , and in natural conditions the females are attracted to male whydahs giving these songs .
( ed . by t . e . martin & d . m . finch ) . new york : oxford university press .
prinias ' egg colours vary widely but by laying multiple eggs in a nest , cuckoo finches reduce the risk of rejection .
just as expected , we found that the prinias were much more likely to reject the foreign egg after seeing one of the two female species than when they saw a male bird . this showed that they were unable distinguish between the two female species and that the cuckoo’s mimicry is successful , but does not give the cuckoo finch the advantage in the arms race at this site .
, namely the shape of the horny palate and the thick , internally flattened lower mandible , function in breaking and crushing hard seeds . the cuckoo finch ' s crop contains crushed seeds , not intact , hulled ones as do those of the whydahs and indigobirds .
the cuckoo finch has a height of 13 cms and weighs around 20 gms . the head is coloured yellow while the bill is coloured brown . the anomalospiza imberbis has a white coloured throat , brown legs and a yellow coloured back . the eyes are brown .
there are two changes from the sacc . they have changed the name of the diademed plover back to diademed sandpiper - plover and have split the gray - throated warbling - finch , poospiza cabanisi , from red - rumped warbling - finch , poospiza lateralis , with the latter now called buff - throated warbling finch . [ charadriidae , charadriiformes , 2 . 51 thraupidae , core passeroidea v , 2 . 51 ]
host species therefore defend themselves against parasitism by rejecting foreign eggs from their nests , and this selection pressure has resulted in the evolution of superb egg forgeries by cuckoo finches . not only do cuckoo finches closely mimic the colour and pattern of host eggs , but as we have seen , different host - races of cuckoo finches lay different eggs that mimic those of the specific host species they specialise upon . for example , the photo below shows cuckoo finch eggs ( right column ) mimicking the eggs of two different host species ( left column ) : red - faced cisticolas in the first two rows , and tawny - flanked prinias in the last four rows .
our cuckoo finch research focuses on two general questions : exactly how cuckoo finches dupe their hosts into accepting these foreign eggs , and on the genetic mechanisms that allow egg mimicry of different hosts to be evolutionarily maintained . this is a puzzle because we would expect interbreeding among males and females raised by different hosts to cause such specialised adaptations to break down . for more information , see the research page .
cuckoo finches in africa have adopted a unique disguise to help them lay their eggs in other birds ' nests , biologists have found .
the prinias have learned to react aggressively towards the innocent female bishops , which look like female cuckoo finches ,
she said .
the top images show the range of colours and patterns found in prinia eggs , and the proportions of host and foreign eggs used in rejection trials ( ratios of host : foreign eggs ) . lines under the eggs indicate groups originating from the same clutch . the bottom two images show naturally parasitized clutches with one cuckoo finch egg ( left ) or two cuckoo finch eggs ( right ) . both cuckoo finch and host eggs show extensive variation among individuals . prinia eggs have fine lines on them that cuckoo finches do not reproduce ; surprisingly , hosts do not seem to use this fail - safe ‘signature’ in egg rejection decisions . such markings make it easy to distinguish host and parasite eggs . average host egg size for length is 15 . 63 mm ( max = 16 . 98 , min = 14 . 63 ) and breadth is 11 . 42 mm ( max = 11 . 91 , min = 10 . 82 ) from a sample of 40 randomly chosen eggs .
) shells . they have not been observed to double - scratch in the field , nor have captives in an aviary been seen to utilize this method with small grass seeds scattered on sand . the cuckoo finch takes grit and sand , which serve to pulverize hard seeds in the crop ;
cuckoo finches lay multiple eggs in the nests of other birds to make it harder to detect the ' imposters ' , researchers have found .
in all species , there was relatively little phenotypic variation within clutches ( electronic supplementary material , table s1 ) ; however , species differed in the level of among - clutch variation , i . e . polymorphism . we calculated mdp space for each host species and their respective cuckoo finch gens (
cuckoo finches forage on the ground and on erect stems of fruiting heads . they use the bill to crush large seeds , such as sunflower (
the species is a brood parasite , laying its eggs in the nests of cisticolas and prinias . the eggs are white , pale blue or pink with brown , reddish or violet markings . they are 17–17 . 3 mm long and 12 . 5–13 mm wide . the eggs are incubated for 14 days . the young bird fledges after 18 days and remains dependent on its hosts for another 10–40 days . the young of the host bird usually disappear although there have been records of the host ' s nestlings surviving alongside the young cuckoo - finch . sometimes two cuckoo - finch chicks have been found in the same nest .
we used our logistic models of conspecific egg rejection experiments to estimate the proportion of real parasitic eggs likely to be rejected by each host species . we simulated a randomly laying cuckoo finch female by pairing randomly sampled host and cuckoo finch eggs ( of the corresponding gens ) 999 times , and for each pair calculating the phenotypic difference between them for each egg trait . because for red - faced cisticolas the available sample of real cuckoo finch eggs was small ( n = 7 ) , to minimize the risk of identical host–parasite combinations , we chose 50 random host eggs in random order and compared each with a randomly chosen parasitic egg ( thus ensuring a different comparison each time ) , and repeated this process five times , thus generating 250 host–parasite comparisons . we then substituted these standardized values into the rejection models ( reported in the electronic supplementary material , table s3 ) to estimate the probability of egg rejection for each simulated laying event .
you ' re actually more likely to hatch alongside a sibling or half - sibling , since your mother probably laid two eggs in the same host nest . this is not a problem : you ' ll thrive alongside each other . this cuckoo finch chick at left has hatched just before its sibling at right . note the absence of any fine lines ( scribbles ) on the cuckoo finch egg , unlike on tawny - flanked prinia eggs . although these scribbles should be perfect signatures of identifty that reliably inform prinia parents which eggs are their own and which are a parasite ' s , puzzlingly , they often still accept unscribbed eggs .
the cuckoo finch is so similar to the innocent bishops , that the target of the trickery , the tawny - flanked prinia , cannot tell them apart ,
said dr feeney , who did his phd at the anu research school of biology before taking a position at the university of cambridge , united kingdom .
the female african tawny - flanked prinia , a species of warbler , lays eggs in a wide spectrum of colours in an effort to fool cuckoo finches .
an experimental study of co - evolution between the cuckoo , cuculus canorus , and its hosts . ii . host egg markings , chick discrimination and general discussion
this conflict of information can be exploited by a parasitic strategy of repeated laying in the same host nest , such that a parasitic female’s eggs outnumber the host’s own . a simulation model based on our field experimental data demonstrated that a parasite’s eggs are more likely to be accepted if she lays more than one egg in the same host nest , especially when the level of mimicry is also good . this implies a strong adaptive benefit to observed cuckoo finch behaviour : the majority of naturally parasitized nests in the field are composed of clutches in which cuckoo finch eggs are either equal in number to or outnumber host eggs . such repeated targeting of the same nest is unlikely to be explained by a shortage of hosts , as tawny - flanked prinias are abundant at the study site and parasitism levels are only ~ 19 % ( ref . 7 ) . our simulations suggest that approximately a quarter of cuckoo finch breeding attempts have levels of mimicry that afford a benefit from repeated parasitism .
24 g . all are sexually dimorphic . the male cuckoo finch is greenish and yellow . males of the whydahs and indigobirds have extensive black in the breeding plumage , and whydah males have the inner two pairs of rectrices elongated , in contrast to the additional elongated rectrices of the long - tailed male widowbirds in the ploceid genus
here , we show that prinias prioritize a template - based approach to identify foreign eggs , but that they also utilize information about the relative proportions of their own and foreign eggs in making rejection decisions . second , we show that hosts are less likely to reject foreign eggs when they outnumber their own and when the level of mimicry is very good , and correspondingly cuckoo finch eggs are more likely to be accepted under such circumstances . finally , we show that cuckoo finch females have a strategy of repeatedly targeting the same host nests with more than one egg to increase the likelihood of acceptance , and this constitutes a further adaptation by brood parasites to defeat host defences .
the rattling cisticola , intermediate with respect to both strategies of defence , is not currently parasitized at our study site . just as several species potentially suitable as common cuckoo hosts show strong rejection behaviour [ 9 ] , it is likely that the rattling cisticola is a former host that has won the arms race with the cuckoo finch . while some foreign eggs were accepted , experimental eggs were always conspecific and hence likely to be a much closer match to the host clutch than real parasitic eggs ; therefore , this does not preclude consistent rejection of cuckoo finch eggs . if the rattling cisticola is indeed a former host , then implementing both strategies appears to have been a highly successful defence against brood parasitism . ideally , these dual defences would be analysed in a phylogenetic context across a range of hosts to distinguish ancestral from derived levels of defence .
species learn the songs from their foster parents and the birds inherit their mitochondrial genes from their mother . in the first generation , a female indigobird laid an egg in a melba finch nest . the melba finch reared the young indigobird , a female , and the latter became imprinted upon the song of her foster parent . as a breeding adult , she was attracted to and mated with a male paradise - whydah mimic of the melba finch . she was then attracted to nesting melba finches and laid her eggs in their nest , and her hybrid young were reared by the melba finches . the two male whydahs , hybrids in the third generation of this family history , mimicked the songs of the melba finch .
rejection frequency by each host species of real cuckoo finch eggs laid by their respective parasitic gens , based on simulations using logistic models of egg discrimination experiments ( see §2 ) . total frequencies add up to in ( a ) 999 , tawny - flanked prinias , but in ( b ) 250 , red - faced cisticolas ( see §2 ) .
11–12 cm ; 18–21g ( kenya ) , 20–22·5 g ( transvaal ) . small , stocky finch with short tail and short , stubby bill with upper mandible laterally compressed . . .
if female cuckoo finches looked more similar to vidua finches than to weavers , then it would suggest that the cuckoo finch plumage is a product of their shared ancestry . if they looked equally similar to vidua finches and weavers , it would suggest that their plumage has been shaped through shared selection pressures from a shared environment ( for example , having to avoid shared predators ) . however , if they looked more similar to the weavers than the vidua finches , it would suggest that natural selection for mimicry has driven their resemblance .
distribution of cuckoo finch in southern africa , based on statistical smoothing of the records from first sa bird atlas project ( © animal demography unit , university of cape town ; smoothing by birgit erni and francesca little ) . colours range from dark blue ( most common ) through to yellow ( least common ) . see here for the latest distribution from the sabap2 .
cuckoo finches reproduce by stealing something very unusual from other birds : parenting skills . the cuckoos lay their eggs in the nests of other bird species , hoping their young will blend in and be fed . even though other birds have evolved to detect minute differences between eggs , and will eject foreign eggs from their nests , somehow cuckoo finches get by .
brood parasite , mating system not known , but probably polyg - ynous . lays one to two eggs per nest , removing one or more host eggs . incubation 14 days , fledging 18 days . hosts are warblers of the genera cisticola or prinia , host young usually trampled in nest , rarely reared with parasite young . two cuckoo finch young may be reared together .
widowbirds , in which the change is brought about by moult . female cuckoo finches are streaky brown above and whitish below , similar in appearance to females or non - breeding males of
we specifically looked at cuckoo finches , as there is already good evidence of an evolutionary arms race between it and its primary host in southern zambia , the tawny - flanked prinia .
cuckoo finches , like the iconic cuckoos , are brood parasites who lay their eggs in the nests of other birds , to deceive them into raising the parasitic young as their own .
kozlovic , d . r . , knapton , r . w . & barlow , j . c . 1996 . unsuitability of the house finch as a host of the brown - headed cowbird .
the cuckoo - finch is a small finch - like bird , about 11–13 cm long . it has a short tail , large legs and feet , and a large , deep , conical bill . the adult male has a black bill and a yellow head and underparts . the upperparts are olive - green with black streaks . the yellow areas become increasingly bright prior to the breeding season as the feathers become worn . the adult female is buff with heavy black streaking above and light streaks on the flanks ; its face is largely plain buff and the throat is buff - white .
cuckoo finches live in grassland , shrubby woodland , and grassy marshes and swamps . unlike some of their relatives in the present family , however , they are not associated with human activities .
found in cisticola nests in ethiopia were saved as specimens in the british museum ( natural history ) ; examination of these reveals that they are , in fact , young cuckoo finches .
payne , r . ( 2018 ) . cuckoo - finch ( anomalospiza imberbis ) . in : del hoyo , j . , elliott , a . , sargatal , j . , christie , d . a . & de juana , e . ( eds . ) . handbook of the birds of the world alive . lynx edicions , barcelona . ( retrieved from urltoken on 9 july 2018 ) .
of f . willughby in 1676 , and the
red - breasted long - tailed finch
described by g . edwards in 1747 . aldrovandi ' s paradise - whydah is the bird now known as
the species was described in 1868 by the german ornithologist jean cabanis based on a specimen from east africa , probably from the coast opposite zanzibar . it was initially placed in the genus crithagra but later moved to a genus of its own , anomalospiza . the name of the genus means
anomalous finch
with spiza being a greek word for finch . the specific name imberbis comes from latin and means
beardless
.
the village indigobird similarly exploits small termites when they emerge during the rains . straw - tailed whydahs supplement their diet of small grass seeds with both larval and adult insects , which they catch on the ground . the cuckoo finch has been seen on rare occasions to take insects , sometimes hawking these at dusk . it feeds its young with insects , including caterpillars and wasps ( hymenoptera ) . wilsonçs indigobird (
a particularly interesting case involves the cuckoo finch ( anomalospiza imberbis ) and one its many hosts , the african tawny - flanked prinia ( prinia subflava ) . university of exeter ecologist martin stevens told io9 ,
there ' s an extremely high level of variation from one prinia ' s eggs to another .
some birds ' eggs resemble the surface of mars , while other eggs may be green with brown spots .
anomalospiza imberbis ( cuckoo finch ) koekoekvink [ afrikaans ] ; koekoekswever [ dutch ] ; anomalospize parasite [ french ] ; kuckucksweber [ german ] ; tecelão - parasita [ portuguese ] distribution and habitat occurs in patches across africa’s western coast from guinea to cameroon , with a separate population extending from ethiopia through tanzania , zambia and angola to southern africa . here it is uncommon in swaziland , mpumalanga and surrounding provinces , while…
importantly , the cuckoo has evolved to produce eggs that look similar to the prinia ' s eggs . but rather than seek out prinia nests with eggs that look like its eggs , the cuckoo leaves it all up to chance , laying eggs in seemingly random prinia nests . in response to this mimicry , the prinia , like many other host species , has developed mechanisms to tease out imposter eggs .
davies , n . b . , brooke , m . de l . & kacelnik , a . 1996 . recognition errors and probability of parasitism determine whether reed warblers should accept or reject mimetic cuckoo eggs .
naturally parasitized clutches at our study site during 2007–2009 and 2012–2013 are consistent with the prediction that repeated parasitism should benefit the cuckoo finch : of 62 parasitized prinia nests where the final clutch composition was known ( that is , incubation had begun ) , two - thirds contained either two ( 61 % ) or three ( 5 % ) parasitic eggs laid by the same female ( as assessed phenotypically by the human eye ; cuckoo finch eggs are highly variable and distinctive among individuals for colour and pattern 7 , making it relatively easy to identify eggs as belonging to the same individuals ) . parasitic eggs were in the majority in 68 % of nests ( in 36 of 42 cases , no host eggs were present ) , equal numbers of host and parasitic eggs were present in 19 % of nests , and host eggs made up the majority of the clutch in just 13 % of parasitized nests .
( a ) simulations between 999 random pairs of host and cuckoo finch eggs show that as the proportion of parasitic eggs in the nest increases , they are more likely to be accepted . error bars show ±1 s . e . m . ( b ) the probability of rejection also depends on the level of colour difference between host and parasitic eggs : closely matching eggs are less likely to be rejected when they comprise a greater proportion of the clutch .
surprisingly , we found that the prinias were extremely aggressive to both the harmful female cuckoo finches and harmless southern red bishops – treating both as threats . they were not , however , aggressive to males of either species .
less is known about the breeding behaviour of the cuckoo finch . adults and juveniles of this species form flocks both outside and within the breeding season . when not in a flock , a male sometimes sings at a single site for a few minutes , as has been recorded at lochinvar national park , in zambia , and at harare , in zimbabwe . the male ' s courtship displays , with the wings raised , look more like the nest - displays of
= 55 per group ; resampled mean ± s . e . for prinias = 0 . 651 ± 0 . 002 and for red - faced cisticolas = 0 . 382 ± 0 . 002 ) . correspondingly , cuckoo finch eggs laid in tawny - flanked prinia nests were more polymorphic ( mean ± s . e . = 0 . 547 ± 0 . 015 ) than those laid in red - faced cisticola nests ( 0 . 404 ± 0 . 038 ) (
the broad - tailed paradise - whydah is a southern african bird that belongs to the viduidae bird family group which includes birds such as whydahs , indigobirds , cuckoo finch . the description for the broad - tailed paradise - whydah ( latin name vidua obtusa ) can be found in the 7th edition of the roberts birds of southern africa . the vidua obtusa can be quickly identified by its unique roberts identification number of 863 and the detailed description of this bird is on page 1071 . more
i ' ve incorporated the new paper by burns and racicot ( 2009 ) about tachyphonini . the tachyphonini have been rearranged and gained black - goggled tanager and crimson - breasted finch from the incertae sedis tanagers . [ thraupidae , core passeroidea v , 2 . 15 ]
in europe , whydahs and indigobirds have been kept as cagebirds for centuries , being held in esteem for their song and colourful breeding plumage . renaissance scholar michel de montaigne visited the italian city of florence in 1581 and saw them in the medici aviaries . his description of a finch with
its closest relatives are thought to be the indigobirds and whydahs of the genus vidua . these birds are now usually considered to form a family , viduidae . previously they were treated as a subfamily , viduinae , within either the estrildid finch family , estrildidae , or the weaver family , ploceidae .
in this study , we demonstrate a novel evolutionary tactic at play in these interactions . we have previously shown that the tawny - flanked prinia , the most common host of the cuckoo finch , uses several different features of egg colour and pattern to discriminate between its eggs and those of the cuckoo finch . in this study , we first demonstrated that prinias know the appearance of their own eggs and primarily reject foreign eggs based on whether they deviate from this internal template . this is consistent with past work investigating mechanisms of rejection in hosts of other brood parasites 11 , 12 , 13 , 14 , 16 , 20 . however , we further demonstrated that prinias do not simply reject any eggs that differ sufficiently from an internal template regardless of their frequency . instead , they appear to use both template - recognition and discordancy mechanisms to maximize information about egg identity . the two mechanisms are in conflict when host eggs are outnumbered by mimetic parasitic eggs , such that sensory and cognitive mechanisms disagree . we have shown that under such circumstances , hosts prioritize information from the template - recognition mechanism but require greater colour differences to make the correct decision .
nestling and fledgling whydahs and indigobirds are fed by their foster parents . they crouch , twist the head and neck , wave the head from side to side , and beg with the head turned to one side or even upside - down , in the manner of the young of their estrildid hosts . the nestlings and fledglings are fed with seeds regurgitated by their foster parents . in contrast to the whydahs and indigobirds , the young cuckoo finch begs in an upright posture , without waving the head , and it feeds directly , taking insects held in the fosterer ' s bill .
we carried out fieldwork during january–march 2007–2009 , within a ca 800 ha area on and around musumanene farm ( 16°47′ s , 26°54′ e ) near choma , southern zambia . all hosts build woven nests with a side entrance , stitched among the broad leaves of small herbaceous shrubs ( tawny - flanked prinias and red - faced cisticolas ) , or tucked into the base of a shrub or grass tussock ( rattling cisticolas ) . hosts pay strong fitness costs of parasitism since cuckoo finch hatchlings usually outcompete all host young [ 22 ] . hosts removed foreign eggs by puncturing then ejecting them .
, the cuckoo finch , include the bill , the mouth and the palate . the bill is short and stubby , with the outline straight . the jaw is bent downwards at the frontonasal - maxillary hinge at an angle of about 110 degrees in relation to the jugal . inside the mouth , a thick lateral surface is formed by the edge of the maxilla and a broad ventral protuberance that articulates with the jugal bone . this complex forms a crushing surface . the lower mandible of all of the viduids has a thick , flat rostral flange that is expanded ventrally at its posterior margin .
this paper shows experimentally that adult female cuckoo finches ( at left in photo ) in zambia have evolved to resemble harmless and abundant bishop - birds ( right ) , which should help them to slip past being attacked by host parents while they try to lay their egg . however , hosts are not fooled by this attempted deception , and defend themselves against parasitic cuckoo finches and harmless bishop - birds alike . to our knowledge this is the first time that such “wolf - in - sheep’s - clothing” plumage mimicry has been experimentally shown to exist in any adult bird .
if you ' re an adult female , lay your eggs in exactly the same host species as your mother did . hope that at least some of your eggs will match the host clutch more like nest number 13 on the left , than nest number 15 on the right ( in each case , the egg at far right is that of a cuckoo finch , and the others are those of the tawny - flanked prinia host ) . your egg will therefore have a much better chance of being accepted by the host parents ( the whole lot will probably still get eaten by a snake , though ) .
anticipating sacc decisions , hyphens have been removed from : rufous crab hawk , buteogallus aequinoctialis ; many - colored rush tyrant , tachuris rubrigastra ; crowned slaty flycatcher , empidonomus aurantioatrocristatus ; shear - tailed gray tyrant , muscipipra vetula drab water tyrant , ochthornis littoralis ; short - tailed field tyrant , muscigralla brevicauda ; many - colored chaco finch , saltatricula multicolor ; black - backed bush tanager , cnemoscopus rubrirostris ; long - tailed reed finch , donacospiza albifrons ; and gray - hooded bush tanager , cnemoscopus rubrirostris . i have also removed a hyphen from white - headed marsh tyrant , arundinicola leucocephala , which has been added to the sacc proposal .
we found the latter , which suggested that female cuckoo finches have evolved to mimic weavers . we then conducted two field experiments in southern zambia to test whether we could verify this apparent case of mimicry . this meant months of long days watching these birds from the inside of a hide , which was absolutely brilliant !
has a single clear layer of bone on each side of the dorsal mid - line ; the clear region contrasts with the spotted appearance of the skull of other songbirds , in which two layers of bone are joined by columns and the layers are otherwise separated by a layer of air , the mature skull being pneumatized or
ossified
. nearly all adults have an incompletely pneumatized skull . in yearling indigobirds the skull is pneumatized by about half , individuals two years old and older have the skull more than 70 % pneumatized , and fewer than 5 % of all birds have a fully pneumatized skull . cuckoo finch adults also have an incompletely pneumatized skull .
many brood parasites [ such as cuckoo finches ] and hosts are locked in ongoing evolutionary arms races , with parasites evolving attack strategies to get their eggs accepted - such as egg mimicry - and hosts evolving defences - such as egg rejection ,
explained co - author dr martin stevens from the university of exeter .
using simulations based on the egg rejection models derived from experimental data , we found that prinia–cuckoo finches laying randomly in tawny - flanked prinia nests have an average rejection probability of 0 . 492 ± 0 . 008 ( range 0 . 047–0 . 999 ) , and that the distribution of rejection probabilities was relatively even ( figure 3 a ) . red - faced cisticola–cuckoo finches laying randomly in red - faced cisticola nests have an average rejection probability of 0 . 521 ± 0 . 014 ( range 0 . 001–0 . 795 ) ; thus , very similar on average to prinias , but with a less even distribution ( figure 3 b ) .
we were suspicious that adult female cuckoo finches might be employing aggressive mimicry to get into their host’s nest because they look remarkably similar to another group of species that shares their grassy habitats : females of the several common species of weavers , known as bishopbirds or widowbirds . is this coincidence , or a deceptive strategy shaped by natural selection ?
on the evolution of aggressive mimicry by adult cuckoo finches : feeney , w . e . , troscianko , j . , langmore , n . e . & spottiswoode , c . n . 2015 evidence for aggressive mimicry in an adult brood parasitic bird , and generalised defences in its host . proceedings of the royal society of london b 282 : 2015079 .
we found that african cuckoo finches – brood parasites that rely on a different kind of bird to raise their young – have evolved to look like harmless weaver birds in an attempt to deceive their hosts . but we also discovered that their tawny - flanked prinia hosts have caught onto this and responded by being aggressive to anyone resembling their enemy – a form of collective punishment .
in some cases , a brood parasite ' s eggs will look nothing like the host ' s eggs , and this is ok because the host cannot tell the difference . but in other cases , especially those involving cuckoo birds , the parasite ' s eggs and the host ' s eggs have similar patterns or colorations , and this results in some very cool evolutionary arms races .
indigobirds and whydahs , along with other finch - type species , are widely trapped for the cagebird trade . in senegal , hundreds of thousands of birds are captured each year , under permit , for this purpose , yet this activity appears , perhaps somewhat surprisingly , to have no noticeable effect on population numbers . viduids are trapped for the trade also in guinea , mali , tanzania and mozambique , and almost certainly elsewhere , too .
a few indigobirds ringed as adults have been recovered more than 20 km from their breeding site , but nothing is known about the juvenile dispersal of these birds . at the end of the breeding season , some whydahs form large flocks and move many kilometres , and a marked shaft - tailed whydah was recovered 150 km from its earlier site . in the dry non - breeding season , cuckoo finches appear in flocks far from their known breeding areas , and they may , in fact , be seasonal migrants .
paradise - whydahs in zambia , where males in breeding plumage appeared at the same site and chased each other . their plumage and their display behaviour were intermediate between those of indigobirds and those of the long - tailed paradise - whydah , and their song mimicked the songs and calls of the melba finch , the normal host species of the whydah . mitochondrial dna of the hybrid male was like that of the indigobirds , which parasitize and mimic the songs of firefinches . the individual life history of one of these hybrid viduids was recovered from its song mimicry and its mitochondria , as
host species of brood - parasitic birds can evolve features such as spots , squiggles and colours on their eggs that act like ‘signatures ' that are difficult for parasites to forge , helping hosts to detect and reject imposter eggs . in this paper , we show that hosts of cuckoo finches ( as well as hosts of diederik cuckoos ) in zambia have optimised this defence by arranging signature traits in unpredictable combinations . thus , egg signatures are individually distinctive and hard for parasites to mimic , helping hosts distinguish parasitic eggs from their own . the paper arose from mphil research by eleanor caves ( co - authored by martin stevens , edwin iversen and claire spottiswoode ) and the data were all obtained from major john colebrook - robjent ' s wonderful egg collection .
viduids occur in flocks at any time of the year , gathering together in the evening , and they often roost in flocks both in the breeding and in non - breeding seasons . sometimes several species will flock and roost together at night in leafy trees . when gathered together , birds will occasionally produce a harsh
chut
or short chatter ; they do not give song mimicry at their roosting assemblages . it is uncertain whether the actively breeding males join in these roosting flocks or roost alone , but at the end of the breeding season , and still in breeding plumage , they certainly feed together and flock for the evening roost along with the moulting males , as well as the females and juveniles . cuckoo finches have not been observed closely through the day , but the breeding females at all stages of their laying cycle spend much of their time in flocks ; males tend to occur alone on song territories , where they are well - spaced from other males , but they also occur in flocks throughout much of the day .


the siamese algae eater ( crossocheilus oblongus ) is a species of freshwater fish in the carp family , cyprinidae .

this bottom-dwelling tropical fish is found in mainland southeast asia , including the chao phraya and mekong basins as well as the malay peninsula .

its natural habitats are streams and rivers as well as flooded forests during the rainy season .

the siamese algae eater should not be confused with the flying fox ( epalzeorhynchos kalopterus ) or the false siamensis ( garra cambodgiensis ) .

siamese algae eater

siamese algae eater , chinese algae eater and harlequin´s , in my 200 liters planted fishtank .
algae eater , siamese headbreather , sucker loach , sucking loach , and biforated carp .
there is a narrow lighter band above the black band in a false siamese algae eater .
all fins on a false siamese algae eater are yellowish in color except for the pectorals .
) . these fish are very commonly sold as merely algae eater . watch out for its adult size , and temperament . the siamese algae eater , (
specificationsmpnf90 0022 2105manufacturerthat fish placecommon nametrue siamese algae eater scientific namecrossocheilus siamensis originasia max siz . . .
the siamese algae eater is also known as the siamese flying fox , flying fox and siamese fox . it is common in aquarium stores and a very good algae eater . a very similar species , garra taeniata aka epalzeorhynchus sp , is sometimes sold as siamese algae eater which have earned that species the common name false siamese algae eater . a majority the siamese algae eaters that are ( or at least used to be ) sold in united states are in fact false siamese algae eaters . it is also common for shipments of siamese algae eater to contain both siamese algae eaters and false siamese algae eater . this is not surprising as the species live in the same areas and young specimens of the two species school together . you can tell the two species apart by the following facts :
otocinclus catfish care guide - otocinclus vittatus - best nano algae eater . great for brown algae .
the siamese algae eater is an interesting and fun fish to watch , especially when in their natural habitat , being a planted community aquarium . these algae eaters are not to be confused with the chinese algae eater
the siamese algae eater is one of the best algae eater fish . sometimes it is confused with other similar fish like the flying fox . אוכל אצות סיאמי , שועל מעופף , אצות באקווריום
the black horizontal band doesn ' t go all the way to the tail fin on a false siamese algae eater .
right now you are bound to think “ does it really matter if i get the true siamese algae eater or the false one ? ” . the answer is that it very well might . the false siamese algae eater is not as good an algae eater as the true one and more importantly is more aggressive towards other fish species than the siamese algae eater . it is therefore much less suitable for a community aquarium with friendly fish .
the true siamese algae eater ( crossocheilus siamensis ) is one of the most popular algae eaters , especially to help control nuisance algaes in planted . . .
the siamese algae eater is native to thailand and the malay peninsula . it is the only know species to eat red algae and can be a good ally to have when fighting a number of nasty algae such as red algae and brush algae .
in addition , the dorsal fin of the flying fox is more deeply notched than on the siamese algae eater , although this may be slight .
ok , i ' m sure you can see the differences right off the bat between a siamese and chinese algae eater , so i ' m not going to get into that much . but as you can see , the false siamensis and flying fox are very similar in apperance to a true siamese algae eater .
siamese algae eaters need to swim to float . if they stop they sink to the bottom .
common name : siamese algae eater , siamese flying fox , flying fox , siamese fox scientific name : crossocheilus siamensis max size : 6 inches / 15 cm ph : 6 . 5 - 7 ( tolerates a much larger range span ) temperature : 75 - 79˚f / 24 - 26˚c
the flying fox has a smoother edge to the black stripe running along its body — the one on the siamese algae eater has a more ragged edge — with the area above the stripe tending to be uniformly coloured . the scales in this area of the siamese algae eater have dark margins , imparting a net - like pattern .
the chief difference is a large fleshy flap in the corner of the mouth in the flying fox ( epalzeorhynchos kalopterus ) that’s absent in the siamese algae eater ( crossocheilus siamensis ) .
more commonly referred to as the carp family . these bottom - dwelling algae eaters are not to be confused with the chinese algae eater or plecostomus , two other popular varieties of algae eaters among freshwater aquarium owners . the siamese algae eater is indigenous to the main lands of southeast asia including the mekong and chao phraya river basins . they inhabit streams and rivers and will spread into flooded out lowland jungle areas of the malay peninsula during the rainy season .
siamese algae eaters are technically omnivores but lean quite far toward the herbivore side of the spectrum . the algae growth in your aquarium alone will not provide an adequate foods source . sinking food wafers and algae pellets or dried algae sheets will help insure they receive enough food to keep them healthy and full of vigor . siamese algae eaters will readily nibble at green leafy vegetables like lettuce and spinach . these make excellent supplemental food items .
some tips and information on keeping the siamese algae eater - sae . like and subscribe ! music :
drops of h2o ( the filtered water treatment )
by j . lang ( feat . airtone ) urltoken is licensed under a creative commons license : urltoken
siamese algae eater are a medium sized member of the carp family . these fish generally reach a maximum adult length of 6 inches in an aquarium setting . they have slender torpedo shaped bodies with transparent fins . these fish have silver color palettes with a single horizontal stripe beginning in front of their eyes and terminating at the base of the caudal fin . siamese algae eaters have a double set of barbels . barbles are a distinguishing characteristic of the carp family .
another big difference is in behaviour . both the false siamensis and flying fox are solitary , and may become aggressive to others of its kind . the siamese algae eater , on the other hand , is a peaceful schoaler , and does better in a small group of 4 - 6 .
this species is among a handful of near - identical congeners that are traded as ‘siamese algae - eater’ ( often abbreviated to ‘sae’ ) , ‘siamese flying fox’ and ‘crossocheilus siamensis’ . recent work has shown that name to be a synonym of epalzeorhynchos siamensis which was described from tadi province , southern ( peninsular ) thailand by smith ( 1931 ) before being moved to crossocheilus by bănărescu ( 1986 ) .
this species is as earlier mentioned a good algae eater , but in most aquariums they will need other food as well as there simply isn ' t enough algae to sustain a school of siamese algae eaters . they willingly accept all types of live , frozen and flake food . feed them a varied diet with a lot of vegetable matter . if given too little green food in the aquarium they might hurt the plants . young specimens are better algae eaters while older specimens seem to like other food more .
common name : siamese algae eater scientific name : crossocheilus siamensis family : cyprinidae origin : south east asia size : 5 - 6 inches / 12 - 15 cm ph : 7 . 0 - 8 . 0 temperature : 74 - 80 f temperament : peaceful great fish for eating nuisance black / beard algae . excellent in planted aquariums and should be kept in groups of 3 or more .
finally , one last thing i ' ve read about and also observed in my tank concerns the peculiar way a siamese algae eater rests . it doesn ' t lie flat on it ' s belly but keeps propped up slightly with its tail , pelvic and pectoral fins ; prefering low , dense plants like cryptocorynes .
i observed mine doing this very thing the other evening , so it seems only appropriate to end this article with a picture of 3 of my siamese algae eaters resting in the dim evening lights .
the easiest and most apparent difference is the horizontal black stripe running down the body . both the false siamensis and flying fox have a nice smooth black stripe topped with a gold stripe . the true siamese algae eater has a ragged , almost zig - zag black stripe running to it ' s tail , and no gold stripe .
the next thing to look at is the mouth . admittedly it ' s hard to see in the photos , but on close inspection you ' ll notice that the false siamensis and flying fox both have twin pairs of barbells ( the little whisker by their mouths ) , but a true siamese algae eater only has 1 pair .
how to identify the siames algae eater . recently i had the luck of running across 6 beautiful little siamese algae eaters , mistakenly labeled at the pet store as flying foxes . knowing their true identity i immediately bought all 6 , and now that they ' ve settled and i ' ve gotten some good pictures , i ' d like to share with you all some tips on identifying this amazing little fish .
the siamese algae eater is generally considered to be the best all - around algae eater available to aquarists . unfortunately it is easily confused with other similar species ( usually
false siamensis
epalzeorhynchus sp . ) , and is often mislabeled in stores . most of the fish i ' ve seen in canada sold under the name
siamese algae eater
are really epalzeorhynchus sp . a relatively peaceful fish , especially when young , it can become agressive to its own species as it ages , and its quick , darting movements can stress out some more sensitive fish , such as dwarf cichlids or discus . a very hardy fish , it is easy to keep and feed , eating both algae and just about anything else put into the tank , such as flake food , pellets , live foods , parboiled vegetables , etc . it does a diligent job of removing algae from plants without harming them , as well as from decorations and aquarium glass . considered by this aquarist as a necessity in any well - planted aquarium . cover the tank carefully however , as these fish are strong jumpers .
siamese algae eaters leave most plants alone but might eat duckweed ( lemna minor ) and the roots of the water hyacinth . they are best kept in schools . true siamese algae eaters are peaceful and can be kept in community tanks with most other friendly fish . avoid keeping them with long finned fish as they might bite the fins on long finned fish . the aquarium should be at least 25 gallon / 100 l .
siamese algae eaters make excellent additions to a community tank . they have peaceful temperaments and quite frequently ignore the activities of fish in the upper levels of your tank . they should not , however , be housed with fish with long , flowing fins like angelfish and bettas . they are reputed fin nippers . unlike many bottom dwelling species , the siamese algae eater exhibits no sign of territorial aggression toward conspecifics . multiples will school together in home aquariums . it is in fact recommended that these fish be raised in schools . they have a particular affinity to broad leafed aquarium plants and will frequently be found resting atop of them , especially when they are younger . adult fish are more prone to rest on the aquarium substrate . these fish will require a minimum tank size of 25 gallons . the average lifespan of a siamese algae eater is 5 - 7 years but they have been documented to live as long as 10 years .
the siamese algae eater is a hardy fish that can adapt to a wide variety of living conditions as long as extremes are avoided , but they do best in planted aquariums with densely planted areas as well as open areas . siamese algae eaters wants to have at least a few broad leafed plants in the aquarium since they like to rest on top of such leafs . young specimens also use narrow leaves for this . if not provided with suitable plants they rest on the bottom . adult fish are more prone to rest on the bottom even if suitable plants are available .
siamese algae eaters a brief description and benefits of keeping this fish . sea ' s were kept in this small tank only for a week , to remove some bba algae which appeared after the water output flow was rendered and some dead spots were created . music by : andrew komarnjicki etsy shop : urltoken
description - urltoken one of the best known algae eater in aquarium . peaceful and attractive fish . temperature : 20 - 26 °c ph : 6 - 7 . 5 tank : min 100 l fish size : 10 - 15 cm .
now observe the color of the fish itself . you ' ll see that both the false siamensis and flying fox are more colorful , with some yellow or red markings to the fins . the siamese algae eater is rather blandish gold - brown - silver . but a distinctive marking is along the back , where the black outlines the scales , making the top of the fish appear retulicar .
how well do otocinclus catfish eat algae ? a little experiment from the den . . . .
although the body stripe becomes paler when the fish are sparring it doesn’t change in width , and a further simple distinguishing trait is the presence of a dark blotch immediately in front of the anal fin on the underside of the fish . this fish is the one most often referred to as ‘siamese algae eater’ in literature and online , but because it varies slightly with c . langei sensu stricto the possibility that it’s an undescribed species cannot be discounted .
a wonderful fish that is known to even eat red algae . not to be confused with the flying fox or false siamese algae eater . these fish are jumpers though , and won ' t hesitate to leap out of the water . a good cover for the tank is required . new owners of this fish might be unnecessarily distressed by their unusual sleeping behavior . it is not uncommon for these fish to sleep nose down , even upside down , either supported by water flow or jammed into or precariously perched upon aquarium decor and equipment . a true sign of distress however , often indicating , stress from water chemistry issues or stress from persecution by other fish is a blanching out of the black lateral stripe , something that should be taken very seriously , and potential causes investigated immediately . siamese algae eaters regularly blanching out are often only hours away from death .
extremely pleased with my order of 6 siamese algae eaters . they are all very healthy and have acclimated to my tank nicely . shipping process was smooth and package arrived on time tightly packed inside a heated enclosure , due to cold weather conditions . thanks again ! you’ve got my attention .
niederle , j . , 2009 - the aquarium gazette 8 my anabasis with red - algae eaters known as crossocheilus siamensis .
lives mainly in mountain streams and brooks with gravel bottoms . feeds on algae and other plants ( ref . 45563 ) .
siamese algae eaters are hard to sex but females are fatter than males and look more rounded when viewed from above . no other differences are known . nothing is known about breeding this species in aquariums without the aid of hormones . it is reasonable to assume that changes in the water ( temperature , ph , hardness ) and current conditions might trigger spawning in well conditioned fish .
arrived alive and in good condition . they do nibble on black algae but they & apos ; ll eat cucumbers , zucchini and fish food as well .
came in great and did well . they seem to be doing the job that i bought them for , eating the black hair algae in my tank !
‘crossocheilus siamensis’ ( see ‘notes’ ) is famed as a consumer of ‘black brush’ algae ( bba ) , also known as ‘red’ or ‘beard’ algae . these members of the division rhodophyta can be otherwise difficult to remove once established in aquaria so the ‘species’ has achieved huge popularity among hobbyists who maintain planted set - ups .
siamese algae eaters accept a wide variety of water conditions but neutral to slightly acidic water is preferred even if they tolerate ph 5 . 5 - 8 . 0 . the recommended temperature is between 75 and 79˚f / 24 and 26˚c . don’t keep this species in very hard water . they prefer well circulated clean water . it is recommended to oxygenate the water as they like oxygen rich water .
came in the day after i ordered . arrived very healthy and adjusted to the community immediately . they have severely reduced the black beard algae in the tank .
) unless the aquarium is large and well planted , because that species is very aggressive towards all its relatives . i have kept these fish in my 200 l community tank for years bacause this slender algae eating barb is the only known fish that eats the red algae which grows in my heavily planted tank from time to time .
frank , neil ; liisa sarakontu .
algae eating cyprinids from thailand and neighboring areas
. the aquatic gardener : journal of the aquatic gardeners association . aquatic gardeners association .
fish are often bought as algae eaters because they will readily eat algae when young , but with age , their preference changes towards meatier foods , such as prepared aquarium foods , frozen crustaceans and small fish . this change is also reflected in behaviour , which becomes aggressive with age , especially so towards others of their own kind and fish with similar colors .
they were delivered timely and in good health . they came in separate bags exactly as i requested because they were going into different tanks . it took them about a week to do any algae eating , but they now have done a nice job of cleaning up the hair algae . they are very cute and one likes to school with my large school of rummy nose tetras !
) is an active and fast swimmer , which thrives best in schools but can also be kept alone or in pairs . it is a strong jumper and should not be kept in uncovered tank , because it will eventually jump . siamese algae eaters often chase one another , but they never get hurt in these fights . as they are not aggressive , they can be kept in any community tank big enough . their active behavior might stress some sensitive species like dwarf cichlids and prevent them from spawning . they should not be kept with red - tailed sharks (
arrived alive , very healthy , and settled right in . only problem is they don & apos ; t do much eating of the hair algae i bought them for . they seem to eat most anything else except live plants . my otocinclus eat as much of it as they do , very odd
. it is a beautiful , peaceful little schooler that more than anything else is famous for being possibly the only aquarium fish in the world that will eat black brush ( red ) algae . the problem is they ' re not easy ( or downright impossible ) to breed in captivity , and easily mixed up with
in nature crossocheilus species are aufwuchs grazers feeding on algae , diatoms and other phytoplankton , plus associated microorganisms . the use of high - protein foods in the aquarium should therefore be avoided as the fish are unable to metabolise some components efficiently ; regular , prolonged consumption can result in excessive deposits of fat and even organ degeneration .
siamese algae eaters appreciate the company of their own species and may wane and become overly timid if kept in solitary conditions . this is a communicative species that requires shoal numbers for their full personality to be appreciated , they will sleep in groups , and feed in coordinating lines and rows . they will shoal defensively . this is a consistently active fish that may annoy fish of a more delicate temperament such as discus , and corydoras with their incessant flight behaviour . the author recommends an aquarium of at least 40 gallons for four adult specimens . the positive aspects of allowing this fish a social life cannot be ignored as regards their health and vigor . this fish has nothing in common with the antisocial and territorial flying fox as regards personality , and is consistently peaceful throughout its life . scuffles cause no real injuries .
we had problems with black bearded algae in our 85 liter tank . so we bought 4 sae ' s when they were just a couple of centimeters long . they quickly grew to maximum size ( 12 - 14 cm ) , and we had to get a new aquarium . we bought a 530 liter aquarium , and the fishes are now very happy , i think . we have had no problems with black bearded algae after the sae ' s moved in . have in mind that they grow quite large , and should have plenty of space to move on . they are so incredibly fast , that i call them
my 4 small jet fighters
. they are nice to other fish !
i have had my sae for about 10 years . he has grown so big ( about 13 cm and has outlived every fish in my tank . although i have read that he is a good algae eater , mine is a big fat lazy opportunist . he eats more processed food and live food than all my fish put together and has a big fat gut . he or she is also very territorial and won ' t allow any of the fish to have a space of their own . i have a 300 liter tank filled with sweet little community fish , angelfish , a kribensis mother and some grown babies , and some rams . he lays ownership to any spot that another fish wants . i do have to say that he doesn ' t allow other fish to fight . if he sees fish getting aggressive toward one another , he is right there to break it up . he is absolutely a pain in my tank , but i love him .
i have a school of seven sae ' s in my 220 liter community aquarium . they range in size from about 6 cm to 8 cm . i believe these are about the most industrious algae eaters i ' ve seen in my 55 years as a fish hobbyist . i originally purchased them because i read somewhere on the internet that they were the only species that ate what has come to be known as black bearded algae , which is an unsightly pest that is very difficult to get rid of . i had this scourge all over some driftwood and all over my live plants , and it was one of the factors that led to the demise of many of my plants . the sae ' s went to work the instant i put them in the tank , and within a few weeks the driftwood looked like it had just come from the processor - it sparkled a bright brown color . they also went to work on the plants when they got tired of polishing the driftwood . within a few days those leaves that were not destroyed by the algae began to look greener and brighter . the algae was almost gone , and there were no residual holes where the sae ' s had been feasting . since this aquarium is located next to my computer , i get to spend a lot of time watching the fish , and i have never seen the sae ' s resting . they constantly forage on every surface in the aquarium . i have found these little custodians to be a peaceful and most useful addition to this community aquarium , which is populated with several species of near adult rainbowfish , adult congo tetras , adult emperor tetras , and several half grown apistogramma species .
these are the hardest working , most beautiful cleaner fish you can get . i think they are much more attractive than the false siamensis and cae ' s with whom they are commonly confused . once you know what to look for it , is easy to make a distinction . the main thing to look at as the stripe . true sae ' s have a serrated stripe that runs all the way to the tip of the tail . i have 10 sae ' s in my 380 liter and they are constantly looking for algae or leftover food to nibble on . they never stop ! i highly recommend these to anyone with the room for them . they get quite large , i ' ve seen some about 14 cm ! they are a must for a planted tank , as they clean the leaves so well , but cause no damage to the plant whatsoever . they eagerly take flake food , but should always have some sort of vegetable matter in their diet , so if they run out of algae , supplement with sinking algae tabs , mine love them . sae ' s are very peaceful toward other fish , but i ' ve noticed mine can occasionally be territiorial to each other , although i don ' t think they have the ability to cause injury .
this can be further furnished with roots and branches arranged to form a network of nooks , crannies and shaded spots . while the majority of plant species will fail to thrive in such surroundings hardy types such as microsorum , bolbitis or anubias spp . can be grown attached to the décor and bright lighting will promote the growth of algae upon which the fish will graze . in this kind of environment it will display more natural behaviour and can be kept alongside other species that enjoy similar conditions .
presumably this saleability is also one reason why several fishes , including c . langei , are offered under the name . these do browse on bba but to varying extents depending on species and in some cases the availability of alternative food sources . c . atrilimes , for example , shows a preference for fine - leaved , higher plants such as vesicularia spp . but will also feed on various types of algae . c . langei sensu amplo is the most efficient consumer of bba although some reports state that only younger , softer growths are eaten and that the fish should be introduced prior to any potential outbreak .
occur in medium to large - sized rivers and enters flooded fields ( ref . 12975 ) . found on solid surfaces in flowing waters . mostly herbivorous , feed largely on algae , periphyton and phytoplankton , but also take insect larvae or zooplankton . in current , they hold onto fixed objects with their sucker - like mouth . for breathing , water is pumped into the gill cavity through a small spiracle and across the gills for gas exchange . large fish are sold in the markets , smaller ones are used to make prahoc ( ref . 12693 ) . aquarium keeping : needs plant feed ; adults territorial ; in groups of 5 or more individuals ; minimum aquarium size 60 cm ( ref . 51539 ) .
occur in medium to large - sized rivers and enters flooded fields ( ref . 12975 ) . found on solid surfaces in flowing waters . mostly herbivorous , feed largely on algae , periphyton and phytoplankton , but also take insect larvae or zooplankton . in current , they hold onto fixed objects with their sucker - like mouth . for breathing , water is pumped into the gill cavity through a small spiracle and across the gills for gas exchange . large fish are sold in the markets , smaller ones are used to make prahoc ( ref . 12693 ) . aquarium keeping : needs plant feed ; adults territorial ; in groups of 5 or more individuals ; minimum aquarium size 60 cm ( ref . 51539 ) .
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first off let me say that i ' ve searched the internet extensively for info on sae ' s , and i have to admit i am amazed at the conflicting information concerning this innocent little fish . as with everything on the internet , easily half the information posted is either inaccurate or outdated , so it is very possible that something i post is also incorrect . so this is sort of my disclaimer : to the best of my knowledge , what i ' m writing is as accurate as information as i can find .
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an unidentified species of striped crossocheilus feeding in the songgaria river , western thailand .
crossocheilus : from the ancient greek κροσσός ( krossós ) , meaning ‘fringe , tassel’ , and χείλος ( cheílos ) , meaning ‘lip’ , in reference to the barbels on the upper lip in members of this genus .
langei : named in honour of e . a . lange , acting health officer and hospital inspector , dutch east indian army , who forwarded the type specimen to bleeker .
currently considered to occur in borneo , peninsular malaysia , southern and western thailand , and possibly southern myanmar . the distribution of laterally - striped crossocheilus spp . , particularly in thailand , requires further study as some populations may represent undescribed species .
inhabits flowing streams and tributaries with substrates of boulders , pebbles , gravel and sand , often in areas with submerged driftwood or tree roots . the clear , often shallow , water allows sunlight to penetrate the surface and the development of a rich biofilm covering submerged surfaces upon which the fish browse .
it is thought to undergo seasonal migrations during which it can be found in deeper , more turbid water .
this species will do well in most well - maintained tanks but is best - suited to a set - up designed to resemble a flowing river or stream , with a substrate of variably - sized rocks , gravel and some large water - worn boulders .
like many fishes that naturally inhabit running waters it’s intolerant to the accumulation of organic wastes and requires spotless water at all times in order to thrive . it also does best if there is a high level of dissolved oxygen and a decent level of water movement in the tank so a external filters , powerheads or similar should be employed in order to obtain the desired effect .
a good quality dried product ( s ) with added spirulina or similar is ideal but plenty of fresh vegetable matter should also be included in the diet . shelled peas , blanched courgette , spinach and chopped fruit all make good additions to the menu . once settled into the aquarium the fish sometimes ascend into midwater to feed and in a set - up as described above will often be seen browsing the biofilm that tends to form on the rockwork .
generally peaceful and can be maintained alongside many of the more popular species in the hobby although it is perhaps preferable to select fishes from from one of its native countries or rivers . possibilities from thailand alone include botia rostrata and crossocheilus reticulatus plus various cyclocheilichthys , devario , mystacoleucus , rasbora , garra , homaloptera , lepidocephalichthys , nemacheilus , syncrossus , yasuhikotakia and schistura species .
crossocheilus spp . are typically found swimming in loose aggregations in nature and can exhibit shy or skittish behaviour if kept singly or in small numbers . they are shoaling , rather than schooling , fishes which develop a distinct pecking order and are best - maintained in a group of six or more since weaker individuals may be bullied incessantly if smaller numbers are kept . you’ll be rewarded with a more natural - looking display plus interesting behaviour from the fish as they interact with one another .
sexually mature females are normally thicker - bodied than males but it’s impossible to accurately sex young fish by external characters .
not thought to have occured in the hobby although the young fish widely available in the trade are assumed to be farmed via the use of hormones . members of this genus are known to undergo seasonal reproductive migrations in nature , moving upstream during the dryer months and in the opposite direction when water levels rise .
the latter name is not valid , however , and is a synonym of epalzeorhynchos siamensis which is itself a synonym of crossocheilus oblongus , a species described from java . c . oblongus is currently accepted to range throughout indochina and the sunda islands but its identity is unclear although its name is routinely applied to fish in the aquarium trade . it was described as a blueish fish with yellow fins and is almost certainly not the ‘sae’ in the aquarium hobby .
separating the species found on sale as ‘c . siamensis’ is tricky but differences do exist if combinations of characters are considered . c . atrilimes is most - easily identified by observing the distance between the vent and anal fin which in this species is only 1 . 5 - 2 scale widths compared to 2 - 3 . 5 in other species .
the black lateral stripe runs from the snout to the tip of the caudal fin ; the eye is pale brown above the pupil and white below ; maxillary barbels are not visible ; the lateral line is curved ; the fins are a pale dusky yellow colour . depending on mood this species has the ability to change the appearance of the dark body stripe , most obviously during bouts of sparring when it becomes much broader and paler in colour .
c . langei sensu amplo seems to be the other commonly - traded , laterally - striped crossocheilus and can be told apart from c . atrilimes by the following characters : the eye is reddish - golden above the pupil and white below ; it has two pairs of barbels ; the lateral line is essentially straight and passes through the centre of the dark body stripe ; the fins are brownish .
the third fish in the group is an undescribed species sometimes referred to as c . sp . ‘citripinnis’ . it’s a larger fish growing to 150 mm sl and possessing a clearly visible pair of maxillary barbels . the fins are lemon yellow in colour , this becoming more intense as the fish mature ; the dark body atripe doesn’t alter in width or colour when the fish are sparring ; the lateral line is curved and the overall body shape is similar to c . atrilmes meaning they’re easily confused as juveniles . there may also be other , potentially undescribed , species from thailand being traded as c . siamensis but as yet no detailed study has been conducted .
in 2009 tan and kottelata described a new laterally - striped species , c . obscurus , from the batang hari river drainage in sumatra . this species also grows relatively large ( to “at least” 5 . 6″ / 14 . 2 cm ) and is further distinguished as follows : “one pair of rostral barbels , no maxillary barbels ; midlateral stripe with edges not sharply contrasted , slightly curved downward , obscured in largest individuals , continued on median caudal - fin rays , reaching posterior margin ; no black mark between anus and anal fin ; mouth wide ( 30 - 36 % hl ) ” . it’s possible that this one has already appeared in the trade labelled with a different name .
c . oblongus is another name widely misused in the trade but that species has seemingly never been exported and was described as a blueish fish with yellow fins . it’s native to streams of gunung salak mountain in bogor regency , west java , indonesia where collecting of ornamental fishes is almost non - existent . other species of laterally - striped crossocheilus also exist and may be available from time - to - time but are more easily told apart from the group described above .
in c . nigriloba , for example , the dark body stripe uniquely breaks up into a series of blotches when the fish are sparring , stressed or sleeping and the lower caudal fin lobe contains dark pigmentation suffused with red , while c . burmicanus exhibits a patch of blue colouration at the base of the pectoral fins .
to add further confusion the vaguely - similar garra cambodgiensis ( itself often referred to incorrectly as g . taeniata ) is usually sold with the name ‘false sae’ although this one is easily - identifiable as the dark lateral stripe ends at the caudal peduncle , all barbels are tiny and it has a disc - like lower jaw which sometimes develops bright red colouration on the outer lips .
epalzeorhynchos kalopterus is sometimes misidentified as a crossocheilus sp . but exhibits several distinguishing traits , the most obvious of which are the characteristic white - edged , red and black coloured fins . also comparable are the paracrossochilus species from the island of borneo but these are almost unknown in aquaria .
members of crossocheilus are characterised by possessing 8 branched dorsal fin rays , immobile rostral lobes , lacking a dorsal spine and by the fact that the upper and lower lips aren’t connected , the upper being attached to the lower jaw via a thin membrane .
bleeker , p . , 1860 - acta societatis regiae scientiarum indo - neêrlandicae v . 7 ( n . s . , v . 2 ) : 1 - 492 + i - xiii de visschen van den indischen archipel , beschreven en toegelicht . deel ii .
bănărescu , p . m . , 1986 - travaux du muséum d ' histoire naturelle 28 : 141 - 161 a review of the species of crossocheilus , epalzeorhynchos and paracrossochilus ( pisces , cyprinidae ) .
kottelat , m . , 2003 - raffles bulletin of zoology 51 ( 2 ) : 399 - 401 nomenclatural status of crossocheilus burmanicus , c . horai and c . multirastellatus ( osteichthyes : cyprinidae ) .
kottelat , m . , 2013 - the raffles bulletin of zoology supplement 27 : 1 - 663 the fishes of the inland waters of southeast asia : a catalogue and core bibiography of the fishes known to occur in freshwaters , mangroves and estuaries .
ng , h . h . and h . - h . tan , 1999 - zoological studies 38 ( 3 ) : 350 - 366 the fishes of the endau drainage , peninsular malaysia with descriptions of two new species of catfishes ( teleostei : akysidae , bagridae ) .
rainboth , w . j . , 1996 - fao , rome : 1 - 265 fishes of the cambodian mekong . fao species identification field guide for fishery purposes .
su , r . - f . , j . - x . yang and y . - r . chen , 2000 - the raffles bulletin of zoology 48 ( 2 ) : 215 - 221 a review of the chinese species of crossocheilus , with description of a new species ( ostariophysi : cyprinidae ) .
tan , h . h . and m . kottelat , 2009 - ichthyological exploration of freshwaters 20 ( 1 ) : 13 - 69 the fishes of the batang hari drainage , sumatra , with description of six new species .
article about “hormone free” breeding in the current issue of the german amazon magazine # 47 pp . 64 – 66 .
these two species are often confused . dr heok hee ng explains how to tell them apart .
since examination of structures of mouthparts is very difficult , if not impossible with live fishes , the only other way to tell them apart are slight differences to colour pattern .
the fins of the flying fox are generally yellowish , and orange for the caudal fin , with black highlights on the dorsal , pelvic and anal fins .
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this is a hardy species that can adapt to a multitude of living conditions . it is , however , only prudent to provide you with what would be considered premium water parameters for this species .
these fish thrive in softer water with a neutral to slightly acid ph factor . a ph level anywhere in the range of 5 . 5 - 8 . 0 is considered ideal . they prefer water temperatures between
75 - 79˚f . well circulated water with plenty of flow and a high oxygen content will simulate their natural habitat .
the males and females of this species look very similar in appearance . females tend to be a little more rounded than males . this species rarely breeds in home aquariums . their seems to be no information available as to whether or not these fish are commercially bred to supply the demand created from the fish hobby trade , which would tend to indicate that they are not .
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greek , gyrinos = tadpole + greek , cheilos = lip ( ref . 45335 )
freshwater ; demersal ; ph range : 6 . 0 - 8 . 0 ; dh range : 5 - 19 ; potamodromous ( ref . 51243 ) . tropical ; 25°c - 28°c ( ref . 1672 )
maturity : l m ? range ? - ? cm max length : 28 . 0 cm sl male / unsexed ; ( ref . 27732 )
has 9 branched dorsal rays ; 36 - 40 lateral line scales ; no dark spots on pelvic and anal fins ( ref . 27732 ) ; a small dark spot always present behind spiracle ; sometimes tiny tubercles on side of head and large tubercles confined to snout ( ref . 12693 ) .
rainboth , w . j . , 1996 . fishes of the cambodian mekong . fao species identification field guide for fishery purposes . fao , rome , 265 p . ( ref . 12693 )
phylogenetic diversity index ( ref . 82805 ) : pd 50 = 0 . 7500 [ uniqueness , from 0 . 5 = low to 2 . 0 = high ] .
bayesian length - weight : a = 0 . 00389 ( 0 . 00180 - 0 . 00842 ) , b = 3 . 12 ( 2 . 94 - 3 . 30 ) , in cm total length , based on all lwr estimates for this body shape ( ref . 93245 ) .
trophic level ( ref . 69278 ) : 2 . 5 ±0 . 25 se ; based on food items .
vulnerability ( ref . 59153 ) : low vulnerability ( 24 of 100 ) .
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the middle / lower mekong ( thailand , cambodia , lao pdr , viet nam ( e . g . , the mekong delta ( electricity viet nam 2010 ) and the
and from the northern malay peninsula ( southern thailand , peninsular malaysia , and probably associated parts of the mekong drainage in myanmar ( mekong myanmar ( the mae kok , mae sai , and kengtung ) ) .
28 . 0 cm sl ( male / unsexed ; ( ref . 27732 ) )
has 9 branched dorsal rays ; 36 - 40 lateral line scales ; no dark spots on pelvic and anal fins ( ref . 27732 ) ; a small dark spot always present behind spiracle ; sometimes tiny tubercles on side of head and large tubercles confined to snout ( ref . 12693 ) .
inhabits flowing streams and tributaries with substrates of boulders , pebbles , gravel and sand , often in areas with submerged driftwood or tree roots ( rainboth 1996 ) . it is thought to undergo seasonal migrations during which it can be found in deeper , more turbid water and is known to enter temporarily - inundated zones .
occurs in medium to large - sized rivers and enters flooded fields ( taki 1978 ) . it is a good indicator of stream / river quality ( c . vidthayanon pers . comm . 2011 ) .
demersal ; potamodromous ( ref . 51243 ) ; freshwater ; ph range : 6 . 0 - 8 . 0 ; dh range : 5 - 19
potamodromous . migrating within streams , migratory in rivers , e . g . saliminus , moxostoma , labeo . migrations should be cyclical and predictable and cover more than 100 km .
the following is a representative barcode sequence , the centroid of all available sequences for this species . there are 3 barcode sequences available from bold and genbank .
below is a sequence of the barcode region cytochrome oxidase subunit 1 ( coi or cox1 ) from a member of the species .
the species has a wide distribution from southern china and southeast asia ( thailand , lao pdr , cambodia and viet nam ) .
populations have declined in some parts of its range ( e . g . , thailand ) as a result of over - exploitation . although considered threatened in china and viet nam , and perhaps naturally rare , it is assessed as least concern at present as it is not thought likely to have declined sufficiently across its range in order to qualify for a threatened category .
it is naturally rare / uncommon in china and southern viet nam ( mekong delta areas ) , but is locally common in viet nam ' s mekong tributaries ( the se san and sre pok ) and the chao phraya - mae khlong basin and the tonle sap basin . populations in thailand have declined ; it was an important component of fish sauce (
although the species may be impacted by dams , not enough is known about its migratory habits to predict the scale of impacts . populations have declined locally , especially in thailand , as a result of a range if factors , including over - exploitation .
more information on the species ecology , threats and distribution is required . listed as a protected animal in yunnan province in 1989 and considered endangered ( wang 1998 ) , and considered rare in viet nam ( huynh 1998 ) .
it is of interest as a local food source and for the aquarium trade , being first imported into germany in 1956 .
the fish spends most of its time on flat surfaces , such as rocks , in flowing water , using its unusually formed inferior mouth to attach itself to rocks in stronger flows .
the fish are sold in local markets as a food source and small fish are used in preparation of prahok .
has been recorded as reaching at least 28 cm ( 11 . 02 in )
and is the only species in the genus to have 9 branched dorsal rays and 36 - 40 lateral line scales .
the mouth is inferior with a special
sucker
modification which allows the fish to attach itself to smooth surfaces . no barbels are present .
wild type colour varies from pale grey to olive , with darker markings along the lateral line which vary from a solid stripe with alternating higher and lower extensions to uneven dots . the belly is usually paler than the base colour . some darker markings may also be observed along the back and on the caudal fin , but no dark markings occur on the pelvic and anal fins .
and is sometimes misidentified as one of these species . it is available in a number of colour morphs , including wild type , gold , marble ,