angwantibos are the two species of strepsirrhine primates that are classified in the genus arctocebus of the family lorisidae .

they are also known as golden pottos because of their yellow or golden coloration .

angwantibos live in tropical africa and their range includes nigeria , cameroon north of the democratic republic of congo .

angwantibos grow to a size of 22 to 30 cm , and have almost no tail at all .

they only weigh up to 0.5 kg .

their fur is yellow brown to golden in color .

their snout is more pointed than that of the other lorids and this , along with their round ears , gives it the bear-like appearance that lends them their name in german : bärenmaki , " bear lemur " .

solitary , nocturnal and arboreal , they prefer the underbrush and the lower layers of the forests .

they spend the day hidden in the leaves .

like all lorisids they are characterized by slow movements .

the diet of angwantibos consists predominantly of insects ( mostly caterpillars ) , and occasionally fruits .

owing to their careful movements and their good sense of smell , they can quietly stalk and close-in on their prey and catch it with a lightning-quick movement .

the males mate with all available females whose territory overlaps with theirs .

copulation takes place hanging onto a branch .

gestation lasts 130 days and births are of a single offspring .

the juvenile clasps itself first to the belly of the mother and later she may park her offspring on a branch while she goes searching for food .

within three to four months the young are weaned , at about six months it leaves its mother , and at an age of eight to ten months it becomes fully mature .

the life expectancy of angwantibos is at most 13 years .

a subplot in gerald durrell 's first book the overloaded ark centres on his attempts to secure an angwantibo for zoological study .

angwantibo

calabar angwantibo - arctocebus calabarensis the calabar angwantibo is found in cameroon and nigeria . source : animal diversity web intended audience : general reading level : middle school teacher section : yes
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the golden angwantibo is closely related to the calabar angwantibo , arctocebus calabarensis , and was previously considered a subspecies of the latter . however , it can be distinguished by its smaller size , more slender build and shorter , brighter red - orange fur ( 4 ) ( 5 ) ( 6 ) .
the golden angwantibo is classified as least concern ( lc ) on the iucn red list ( 1 ) and listed on appendix ii of cites ( 3 ) .
the calabar angwantibo ( arctocebus calabarensis ) , also known as the calabar potto , is a strepsirrhine primate of the family lorisidae . it shares the genus arctocebus with the golden angwantibo ( arctocebus aureus ) . it is closely related to the potto ( perodicticus potto ) and to the various lorises . the calabar angwantibo lives in the rain forests of west africa , particularly in tree - fall zones . in areas where the forest has been cleared , it has been known to live on farmland .
the main threat to the golden angwantibo is habitat loss , due to logging and cultivation ( 1 ) ( 2 ) ( 7 ) . in addition , although it is thought to be too small and cryptic to face much danger from human hunters ( 4 ) , traps are not selective , meaning the golden angwantibo may be threatened by traps set for other species , particularly in light of its habit of coming down to the ground ( 8 ) . the opening up of previously inaccessible areas for logging may lead to increased hunting pressure ( 9 ) , and there may also be indirect effects of poaching of other species ; for example , forest elephants help create the areas of secondary growth favoured by the golden angwantibo , and the loss of these elephants may therefore reduce golden angwantibo habitat ( 8 ) . the relatively limited distribution of the golden angwantibo makes it more vulnerable to these threats than more widespread species ( 10 ) .
the golden angwantibo ( arctocebus aureus ) is a small , nocturnal primate with thick , woolly fur , which , as its name suggests , is golden - red or orange in colour . the underparts are creamy or greyish , and fine guard hairs on the back , shoulders and haunches have crinkled tips , giving the fur a frosted appearance . the head is rounded , with a pointed , narrow muzzle , the ears are small and rounded , and the eyes are large , giving the golden angwantibo excellent night vision ( 2 ) ( 4 ) ( 5 ) . the golden angwantibo has no tail , and , instead , its extremely powerful grip , made possible by a specialised arrangement of blood vessels in the wrists and ankles , aids it in moving securely through the trees ( 2 ) ( 6 ) . in common with other loridae ( lorises , pottos and angwantibos ) , the golden angwantibo has nails on all digits except for the second digit of each foot , which possesses a ‘toilet claw’ , used in grooming ( 2 ) ( 6 ) . interestingly , the index finger is reduced to a mere stub ( 2 ) ( 5 ) ( 6 ) .
the golden angwantibo has a widespread but patchy distribution in the tropical forests of west africa , in cameroon , congo , gabon , equatorial guinea , angola and central african republic ( 1 ) ( 4 ) . it occurs south of the sanaga river in cameroon , and east as far as the congo and ubangui rivers in congo ( 7 ) .
…but much smaller primates called angwantibo s ( arctocebus calabarensis and a . aureus ) live only in the rainforests of west - central africa . they measure 24 cm ( 9 . 5 inches ) long and are yellowish in colour , with a long , thin snout . like the potto , they are tailless , but the third finger as well as the…
active mainly at night , the golden angwantibo sleeps by day in thick foliage or in the shelter of tree crevices . it moves through the trees on all fours , using a slow , deliberate , ‘hand - over - hand’ movement , and crosses between trees by stretching between terminal branches , rather than by leaping or jumping ( 2 ) ( 6 ) ( 7 ) . on the ground , the golden angwantibo shows a unique defensive behaviour . if threatened , it stands with limbs rigid , widely spaced and fully extended , and the head tucked into the chest . if touched , it may lunge at the attacker from between the legs , with a quick , slashing bite ( 4 ) . alternatively , when in the trees , it may simply roll into a ball while clinging tightly to a branch ( 2 ) ( 5 ) .
the golden angwantibo feeds mainly on insects and other invertebrates , particularly caterpillars , which it supplements with fruit ( 2 ) ( 5 ) ( 7 ) . it may even rear onto its hind legs and use the hands to catch moths in flight ( 2 ) ( 5 ) . the golden angwantibo eats many unpalatable and even poisonous invertebrates ( 4 ) , and is thought to have an unusually slow metabolism which may allow undesirable chemicals to be neutralised in the gut ( 6 ) . although mainly solitary , the golden angwantibo may occasionally meet with other individuals with whom its home range overlaps ( 5 ) ( 6 ) . most communication is through scent ( 4 ) ( 6 ) , particularly through urine marks ( 7 ) . the female gives birth twice a year , to a single infant ( 1 ) , after a gestation of between 131 and 136 days . births may occur at any time of year , but are most often recorded during the wet season ( 7 ) . the infant clings to the female’s belly for the first three to four months , after which it is weaned , and begins to follow the female or ride on her back . individuals become sexually mature at around eight to ten months and may live for up to thirteen years ( 2 ) .
the golden angwantibo is listed on appendix ii of the convention on international trade in endangered species ( cites ) , meaning international trade in the species should be carefully controlled ( 3 ) . it is also protected by law in gabon , and is listed under class b of the african convention , which only allows it to be legally hunted , killed or captured with special authorisation ( 1 ) ( 11 ) . it is presumed to occur in a number of the new national parks in gabon ( 1 ) , and its ability to live in secondary forest may help the golden angwantibo to survive in habitats that have been disturbed by humans ( 2 ) . however , the species is difficult to census thoroughly because of its nocturnal and secretive habits , and it has been understudied in the wild , meaning more research is needed to more fully understand the ecology and social organisation of this poorly known primate ( 10 ) and to better establish its true conservation status ( 1 ) .
the golden angwantibo inhabits moist evergreen , lowland forest , preferring areas with fallen trees or young secondary growth . it is generally found in the understorey , below five metres , and may also venture onto the forest floor in search of food . it avoids climbing higher than about 15 metres , where the risk of predation , competition with birds , and exposure to wind and sun is higher , and also avoids climbing larger branches which its small , narrow hands and feet are not suited to grasping ( 4 ) ( 7 ) .
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i thought you might be interested in this item at urltoken title : mammal species of the world : a taxonomic and geographic reference author : don e wilson ; deeann m reeder publisher : baltimore : johns hopkins university press , ©2005 . isbn / issn : 0801882214 9780801882210 0801882389 9780801882388 0801882397 9780801882395 oclc : 57557352
wilson and reeder ' s mammal species of the world is the classic reference book on the taxonomic classification and distribution of the more than 5400 species of mammals that exist today . the third edition includes detailed information on nomenclature and , for the first time , common names . each concise entry covers type locality , distribution , synonyms , and major reference sources . the systematic arrangement of
information indicates evolutionary relationships at both the ordinal and the family level . this indispensable reference work belongs in public and academic libraries throughout the world and on the shelf of every biologist who works with mammals .
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this indispensable reference work belongs in public and academic libraries throughout the world and on the shelf of every biologist who works with mammals .
a uniquely valuable compendium of taxonomic and distributional data on the world ' s living and historically extinct mammalian species . contributors and editors alike deserve the thanks of all
mammalogists for helping to forge the nomenclatural mesh that holds our science together . * journal of mammalogy * to refer to this work as a checklist undervalues it and does not give sufficient credit to the authors and editors for their meticulous efforts in its production . a valuable reference work and a vital tool , particularly for researchers . * journal of natural history * by far the most convenient source for finding the correct scientific name of any mammal and should be on the reference shelf of libraries striving to have useful science sections . * science books and films * the editors and authors are to be congratulated for undertaking such an outstanding and authoritative work , and it should serve as a standard reference for mammalian species taxonomy for many years to come . * journal of mammalian evolution * the third edition adds to its reputation as an outstanding and authorative work . * national museum of natural history weekly update & forecast * impressive and elegant work . - - g . r . seamons * reference reviews * a must - have text for any professional mammalogist , and a useful and authoritative reference for scientists and students in other disciplines . * southeastern naturalist * a magnificent work important to anyone seriously interested in mammals . this work is essential for academic or special libraries supporting zoology or conservation and for large public libraries . * american reference books annual * as were many of our colleagues , we were waiting for this revised edition since 2003 . . . we can say that the wait was worth it . - - sergio solari and robert j . baker * journal of mammalogy *
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wilson and reeder ' s mammal species of the world is the classic reference book on the taxonomic classification and distribution of the more than 5400 species of mammals that exist today . the third edition includes detailed information on nomenclature and , for the first time , common names . each concise entry covers type locality , distribution , synonyms , and major reference sources . the systematic arrangement of information indicates evolutionary relationships at both the ordinal and the family level . this indispensable reference work belongs in public and academic libraries throughout the world and on the shelf of every biologist who works with mammals .
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authenticated ( 12 / 10 / 10 ) by dr elizabeth pimley , senior ecologist , worcestershire wildlife consultancy . urltoken
evergreen forest forest consisting mainly of evergreen trees , which retain leaves all year round . this is in contrast to deciduous trees , which completely lose their leaves for part of the year . gestation the state of being pregnant ; the period from conception to birth . guard hair in some mammals , long , coarse hairs that protect the softer layer of fur below . home range the area occupied by an animal during routine activities , which is not actively defended . invertebrates animals with no backbone . nocturnal active at night . secondary forest forest that has re - grown after a major disturbance , such as fire or timber harvest , but has not yet reached the mature state of primary forest . subspecies a population usually restricted to a geographical area that differs from other populations of the same species , but not to the extent of being classified as a separate species .
nowak , r . m . ( 1991 ) walker’s mammals of the world . the johns hopkins university press , baltimore and london .
kingdon , j . ( 1997 ) the kingdon field guide to african mammals . academic press , london .
ankel - simons , f . ( 1999 ) primate anatomy : an introduction . academic press , san diego , california .
macdonald , d . w . ( 2006 ) the encyclopedia of mammals . oxford university press , oxford .
blom , a . , alers , m . p . t . , feistner , a . t . c . , barnes , r . f . w . and barnes , k . l . ( 1992 ) primates in gabon - current status and distribution . oryx , 26 ( 4 ) : 223 - 234 .
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mittermeier , r . a . , rylands , a . b . and wilson d . e . 2013 . handbook of the mammals of the world : volume 3 primates . lynx edicions , barcelona .
justification : listed as least concern in view of its tolerance of some degree of habitat modification and since it persists quite well in secondary degraded forest . however , in eastern nigeria , there is some hunting pressure which if continues unabated may place this species in a higher category of threat .
this species is found in western equatorial africa , with a very patchy and localised distribution within the lowland rainforest block between the niger river and the sanaga river in nigeria and cameroon .
a cryptic species that is thought to be locally abundant within its patchy distribution . originally , they were particularly adapted to clearings in the forest and towards the forest edge .
confined to areas of very dense , low undergrowth with abundant lianas and vines within the understorey of primary , secondary , and coastal rainforest . this species particularly favours the growth that springs up in clearings , trees falls , and along forest edges . wherever it is already established , small - scale clearances , selective tree - felling , and road - making probably favour this species . in such areas it is likely to become abundant in thickets and patches of dense secondary growth . it feeds mainly on caterpillars ( which are found by smell ) , and also on beetles and fruits . this species is able to produce two young in a year .
major threats are habitat destruction from forestry and clearance for cultivation , as well as some hunting for meat in nigeria . this species will not be affected by low - level habitat disturbance , since it is able to inhabit secondary forests as long as dense undergrowth remains and inter - tree distance are not too great . however , broader clearances ( e . g . those made for plantations , clear - felling , and agriculture ) are likely to eliminate it because of its weak capacity to disperse .
this species is listed as class b under the african convention , and under appendix ii of cites . it is known to occur in cross river national park ( nigeria ) and korup national park ( cameroon ) . it probably occurs in a few others in the area , although its presence is not confirmed . further surveys are needed to determine its true conservation status .
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justification : listed as least concern as the species is relatively widespread in central africa , and there are no known major threats resulting in a significant population decline .
this species may occur from the sanaga river to the congo river / ubangi river , but with a very localized and patchy distribution . the range limits of this species are poorly known .
this cryptic species is considered rare in gabon , where densities of 2 individuals / km² were found in dense primary forest and 7 / km² in thickets in secondary forest . normal census methods are impossible because it hides its head and eyes at the least disturbance .
confined to vine tangles and areas with abundant young ( or slow - growing ) leafy stems in the understorey of moist evergreen , lowland rainforests . large vertical branches are never climbed because the small , narrow hands and feet of this species are adapted only to close around stems less than 6 cm in diameter . this species avoids climbing higher than 15 m ( it mostly lives below 5 m ) due to heightened competition from birds , less consistent insect resources , more exposure to wind , sun , and predators , and fewer thin - branched tangles to shelter in . it frequently descends to the forest floor for fallen fruits and invertebrates . caterpillars of all species are eaten , including hairy and distasteful species that are avoided by other insect - predators . the females give birth to one infant twice per year .
this species is too small and cryptic to face much danger from human predation . clear - felling and large - scale clearances are the only major threat to their habitat .
this species is protected by law in gabon . it is listed as class b under the african convention , and under appendix ii of cites . it is presumably in a number of the new national parks in gabon . this is a poorly known species in need of further research .
, are endemic in western equatorial africa , and are found in cameroon , equatorial guinea , nigeria , and zaire .
can be found in primary and secondary forests , where it prefers tree fall zones . this species also resides within forestry and agricultural plantations .
is adapted to undergrowth , foraging within the lower canopy of the forest . it will spend most of its time within 5 m of the ground .
can range from 266 to 465 grams . the head - body length ranges from 229 to 305 mm . this species has a reduced , nub - like tail that measures from 4 to 10 cm , along with a reduced index finger . the second digit on each toe is used as a grooming claw .
pelage coloration ranges from orange to yellow to brown on the dorsal side , with white or buff pelage on the ventral side . facial markings include a white stripe above the nose .
males mate polygynously , copulating with the females whose home ranges overlap their territories . a female signals to a male that she is ready to mate by suspending herself upside down from a branch . both male and female suspend themselves upside - down from a branch during copulation .
females have an estrous cycle of 36 to 45 days . gestation lasts between 131 and 136 days . they are capable of breeding more than one time per year , although details on interbirth intervals are not available .
the breeding season typically begins in the middle of the dry season and lasts until the start of the wet season . because of this , golden pottos can breed more than once per year . golden pottos copulate only at the end of the estrous cycle , when the female is about to ovulate . the female signals to the male that she is ready to mate by suspending herself upside down from a branch . both male and female suspend themselves upside - down from a branch during copulation .
females give birth to a single offspring . the young potto clings to the belly of the mother for about 4 months . young are weaned between three and four months of age , at which time they begin to ride on their mother ' s back . young leave the mother ' s home range around six months of age . they reach sexual maturity around 18 months .
breeding season breeding begins in the middle of the dry season and ends at the beginning of the wet season .
males are not known to provide parental care in this species . at birth , the young are able to cling to the mother ' s fur , and have their eyes open . they are not able to climb or walk well on their own . the female cares for the young , carrying the infant first on her belly and later on her back . females nurse their offspring for 3 to 4 months , and forage with them in the underbrush for another 2 months . at about 6 months of age , the young disperse .
in the wild , golden pottos can be expected to live anywhere from 12 to 15 years with an average life expectance of 13 years . when kept in captivity the lifespan of
males have home ranges which overlap the home ranges of 2 to 3 females . pottos are solitary animals who forage and sleep alone , although throughout the year , a male makes contact with females resident in his home range .
this species moves slowly and is a quadrupedal climber . while climbing , three of a golden potto’s limbs are always grasping for support while swinging from branch to branch . golden pottos are nocturnal and arboreal , sleeping within thick foliage cover . ( nowak , 1999 )
communication in this species has not been well described . vocalizations are recorded . in addition , the visual signal of a female positioning herself for copulation is important in breeding . presumably , as in other prosimians , there is scent marking of territories . tactile communication is important between mother and offspring , as well as between mates .
golden pottos are primarily insectivorous , eating mainly insects that are rejected by other insectivores . caterpillars are among the most common insects consumed by
. other insects consumed include beetles , ants , moths and crickets . before eating a caterpillar , golden pottos will rub the caterpillar in their hands to remove any hair the caterpillar may have . this prevents irritation from defensive hairs on the caterpillars . golden pottos will also eat fruit and gums .
this species tends to forage alone within the lower canopy or on the ground within the undergrowth . although golden pottos generally move slowly , they have been observed quickly rearing on their back legs in order to snatch moths from the air .
details on predation of these pottos are not available , although they presumably fall victim to small carnivores , and the standard nocturnal predators of equatorial africa .
is known to roll up into a ball when threatened , keeping the face under the armpit . if attacked , golden pottos will bite the predator on the snout , not letting go . infants cling to the mother if she appears alarmed . newborns are born with eyes open and can cling to their mothers ' fur or to tree branches . in order to avoid birds of prey , these primates rarely climb higher than 15 m . ( charles - donimique , 1977 )
golden pottos help to disperse seeds of the fruit they have eaten by defecation ( nowak , 1999 ) .
golden pottos are hunted for their meat by humans ( kingdon , 1997 ) .
is a cites appendix ii species , which means there are restrictions and guidelines pertaining to the trade and exploitation of this species . this species also faces habitat destruction as the rainforests are cut down for timber and to open up farmland . although these pottos are adapted to secondary vegetation , they are unable to disperse across unforested areas . ( kingdon , 1997 )
taryn olson ( author ) , university of wisconsin - stevens point , chris yahnke ( editor ) , university of wisconsin - stevens point .
living in sub - saharan africa ( south of 30 degrees north ) and madagascar .
young are born in a relatively underdeveloped state ; they are unable to feed or care for themselves or locomote independently for a period of time after birth / hatching . in birds , naked and helpless after hatching .
having body symmetry such that the animal can be divided in one plane into two mirror - image halves . animals with bilateral symmetry have dorsal and ventral sides , as well as anterior and posterior ends . synapomorphy of the bilateria .
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature . endothermy is a synapomorphy of the mammalia , although it may have arisen in a ( now extinct ) synapsid ancestor ; the fossil record does not distinguish these possibilities . convergent in birds .
offspring are produced in more than one group ( litters , clutches , etc . ) and across multiple seasons ( or other periods hospitable to reproduction ) . iteroparous animals must , by definition , survive over multiple seasons ( or periodic condition changes ) .
the area in which the animal is naturally found , the region in which it is endemic .
rainforests , both temperate and tropical , are dominated by trees often forming a closed canopy with little light reaching the ground . epiphytes and climbing plants are also abundant . precipitation is typically not limiting , but may be somewhat seasonal .
the region of the earth that surrounds the equator , from 23 . 5 degrees north to 23 . 5 degrees south .
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female .
to cite this page : olson , t . 2003 .
arctocebus calabarensis
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there are 10 species of small primates in this family . lorises are found in asia . pottos and angwantibos are found in africa . lorises , pottos and angwantibos have thick , wooly fur ; short or no tails ; and big , round eyes .
the primates in this family live in trees , but unlike other primates , they do not swing or leap from branch to branch . they slowly crawl around on tree branches .
they can crawl on the top of a branch , or hang upside down and crawl on the underside of a branch . lorises , pottos , and angwantibos are nocturnal . they spend the day resting in tree hollows or on tree branches . at night the slowly crawl around the tree branches searching for fruit and insects .
least concern near threatened vulnerable endangered critically endangered extinct in wild extinct status and range is taken from icun redlist . if no status is listed , there is not enough data to establish status .
bengal slow loris - nycticebus bengalensis the bengal slow loris is found in bangladesh , cambodia , china , india , laos , myanmar , thailand , and vietnam . source : arkive intended audience : general reading level : middle school teacher section : yes
bornean slow loris - nycticebus menagensis the bornean slow loris is found in brunei darussalam , indonesia , malaysia , and the philippines . source : arkive intended audience : general reading level : middle school teacher section : yes
gray slender loris - loris lydekkerianus the gray - slender loris is found in india and sri lanka . source : arkive intended audience : general reading level : middle school teacher section : yes
greater slow loris - nycticebus coucang the greater slow loris is found in indonesia , malaysia , singapore , and thailand . source : arkive intended audience : general reading level : middle school teacher section : yes
greater slow loris - nycticebus coucang greater slow lorises are covered with short , thick , woolly fur in a variety of colors and patterns . source : animal diversity web intended audience : general reading level : middle school teacher section : yes
greater slow loris - nycticebus coucang the greater slow loris stays motionless for hours . source : los angeles zoo intended audience : general reading level : middle school teacher section : yes
greater slow loris - nycticebus coucang the greater slow loris eats eat snails , insects , lizards , birds , small mammals , and fruit . source : woodlands park zoo intended audience : general reading level : middle school teacher section : yes
javan slow loris - nycticebus javanicus the javan slow loris is found in indonesia . source : arkive intended audience : general reading level : middle school teacher section : yes
potto - perodicticus potto the potto is found in angola , benin , burundi , cameroon , central african republic , congo , côte d ' ivoire , equatorial guinea , gabon , ghana , guinea , kenya , liberia , nigeria , rwanda , sierra leone , togo , and uganda . source : arkive intended audience : general reading level : middle school teacher section : yes
potto - perodicticus potto pottos have long , slender bodies , large eyes , and small , round ears . source : animal diversity web intended audience : general reading level : middle school teacher section : yes
potto - perodicticus potto pottos leave urine trails along branches to communicate with each other through scent . source : cincinnati zoo intended audience : general reading level : middle school teacher section : yes
pygmy slow loris - nycticebus pygmaeus the pygmy slow loris is found in cambodia , laos , and vietnam . source : animal diversity web intended audience : general reading level : middle school teacher section : yes
slender loris - loris tardigradus the slender loris is found in sri lanka . source : arkive intended audience : general reading level : middle school teacher section : yes
slender loris - loris tardigradus the slender loris is nocturnal and lives in trees . source : animal diversity web intended audience : general reading level : middle school teacher section : yes


leioproctus fulvescens is a species of bee native to the south island of new zealand .

adults are about 10 mm long with dense characteristically yellow to orange-brown hair ; this feature distinguishes them from other new zealand leioproctus species , which have white to cream hairs .

the bees fly primarily in the spring and summer , with the majority of individuals between november to march , though some have been observed as early as september .

the bees nest underground in a variety of soil types , including beach sand , salt flats , dry river banks , clay , garden soil , and compacted dirt and shingle roads ; nearly any soil type appears to be used so long as it is on relatively free of vegetation , has a relatively low level of moisture and a sunny aspect .

females prefer to build their nest tunnels in slightly sloping ground , and dig the main shaft anywhere from 100-500mm into the ground .

along the tunnel , there are often a number of side branches , each terminating in a single oval nesting chamber .

the chamber is lined with a cellophane-like substance which reduces the amount of moisture that can enter the cell , providing a protective chamber for the larvae to develop .

each chamber is provisioned with a ball of pollen and nectar , on top of which a single egg is laid .

once completed , the chamber is sealed up with packed earth .

females forage mainly on plants in the family asteraceae , such as gentiana corymbifera ( snow gentian ) , raoulia , and some of the white flowered hebes such as hebe subalpina .

they have also been observed foraging on introduced asters , such as yarrow and canada thistle .

leioproctus fulvescens

scientific illustration of new zealand native bee leioproctus fulvescens . one of the bees i ' m working with in my current research project .
leioproctus fulvescens , a native colletid of new zealand . now that i have access to the lab’s insect collection , i can finally get reference photos to create as many illustrations as i want .
they dig nest holes in the ground , and sometimes a nesting area riddled with bee holes gives the impression of a colony . a small pile of soil is the usual sign of individual nest tunnels . each species prefers a specific type of soil . for example , leioproctus fulvescens needs fine - grained soil , while leioproctus metallicus nests in coastal sand .
the most commonly seen native bees are 18 species of leioproctus . these bees are robust and hairy , looking similar to honeybees but smaller ( 5–12 millimetres long ) . all are black except for the south island species leioproctus fulvescens , which is covered with dense orange–yellow hair . they are often seen in summer carrying pollen on their back legs , like honeybees and bumblebees .
the yellow hairs are a key character of l . fulvescens . there are 18 leioproctus species in new zealand , but l . carinatifrons is not one of them , as it is native to australia . you might come to nz ? cool !
the south island species that is pictured above and below is the most colourful of our native bees , leioproctus fulvescens . although they have quite cosmopolitan tastes , members of the daisy family ( such as the olearia cymbifolia shown in these images ) are important sources of pollen for l . fulvescens . on a sunny day in the mackenzie basin , large numbers of this conspicuous bee can be viewed going about their business .
flax ( phormium spp . ) do not just extend their largesse towards our native birds ( who avidly feed upon their nectar ) , as shown by the leioproctus sp . pictured below , which was emerging from a phormium tenax flower in west auckland . it clearly displays the ' pollen pellets ' that bees collect on their hind legs as they harvest , a feature that is also evident in the photograph of leioproctus fulvescens above .
the final image shows an individual of leioproctus fulvescens visiting a celmisia gracilenta flower amidst degraded tussockland near the glenmore tarns . amidst all of the legitimate concern regarding the decline of honeybees throughout the world , it is also important to be conscious of maintaining healthy populations of other pollinators from our environments ( such as native bees , butterflies and new zealand ' s diverse and significant range of fly species ) .
oh man , this is quite detailed . not sure if this is what i will expect to see if my family does move to new zealand ( being their
native bee
. ) it amazes me how species that superficially look the same can be so different in minute ways . seems this bee someone told me was a new zealand native bee was actually leioproctus carinatifrons . ( is it possible for the fulvescens species not to have the orange - yellow hairs ? )
half - healed , half fresh , but man , am i super psyched to have wrapped up this tattoo on josh today . also a little sad ! it’s been so fun to work on ! new zealand and northern european native birds , plants , and insects . trees are pohutukawa , birch , beech , rowan ; birds are tui , kea , house swallow , and raven ; today added a magpie moth and two leioproctus fulvescens bees . hopefully i’ll snag some healed photos before he heads back to nz ! detail post after this .
ooh , thank you for clearing that up ! that ' s what i read about l . fulvescens as well , but i have not seen even a preserved specimen for myself . i ' m not very sure . we have friends ( and some relatives ) in australia , but a high school classmate of mine lives in nz . she ' s been inviting me to visit her for a while , now .
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flies , caddisflies , craneflies , damselflies dragonflies , gnats , mayflies . midges , mosquitoes
insects ( ants , beetles , bugs , cicadas , cockroaches , centipedes , crickets , grasshoppers , lacewings , ladybirds , mantis , millipedes , scale , shield bugs , stick insects , wetas , weevils , etc . ) .
reptiles ( frogs , geckos , skinks , snakes , lizards , turtles ) .
trees & shrubs ( new zealand native ) botanical names a to f with photo .
trees & shrubs ( new zealand native ) botanical names g to l with photo .
trees & shrubs ( new zealand native ) botanical names m to q with photo .
trees & shrubs ( new zealand native ) botanical names r to z with photo .
trees ( new zealand ) hebes and their hybrids & cultivars ( photos ) .
weeds & escapee plants : a to f ( common names with photo ) .
weeds & escapee plants : g to l ( common names with photo ) .
weeds & escapee plants : m to q ( common names and photo ) .
weeds & escapee plants : r to z ( common names with photo ) .
© copyright 2008 - 2018 - t . e . r : r . a . i . n . all rights reserved . last update : 27 - nov - 17 . site designed & hosted by smokeylemon .
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griswold , t . , d . yanega , et al . ; as - yet unpublished manuscript
john ascher , connal eardley , terry griswold , gabriel melo , andrew polaszek , michael ruggiero , paul williams , ken walker , and natapot warrit . additional credits noted at : urltoken ; = apoidea _ species
disclaimer : itis taxonomy is based on the latest scientific consensus available , and is provided as a general reference source for interested parties . however , it is not a legal authority for statutory or regulatory purposes . while every effort has been made to provide the most reliable and up - to - date information available , ultimate legal requirements with respect to species are contained in provisions of treaties to which the united states is a party , wildlife statutes , regulations , and any applicable notices that have been published in the federal register . for further information on u . s . legal requirements with respect to protected taxa , please contact the u . s . fish and wildlife service .
ella mai – boo ' d up ( remix ) ft . nicki minaj & quavo
confused by a class within a class or an order within an order ? please see our brief essay .
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 .
disclaimer : the animal diversity web is an educational resource written largely by and for college students . adw doesn ' t cover all species in the world , nor does it include all the latest scientific information about organisms we describe . though we edit our accounts for accuracy , we cannot guarantee all information in those accounts . while adw staff and contributors provide references to books and websites that we believe are reputable , we cannot necessarily endorse the contents of references beyond our control .
this material is based upon work supported by the national science foundation grants drl 0089283 , drl 0628151 , due 0633095 , drl 0918590 , and due 1122742 . additional support has come from the marisla foundation , um college of literature , science , and the arts , museum of zoology , and information and technology services .
like wasps , bees may be solitary or social . they feed on nectar and pollen , and play an important role in the pollination and survival of many flowering plants . new zealand has 28 native and 13 introduced species of bee .
at least three native bee species have a basic social structure , a bit like the introduced honeybee and bumblebee . the rest are solitary , although they may make nests close together .
native bees pollinate many native plants . they are also widespread in kiwifruit and apple orchards and some vegetable crops , and may be important pollinators in horticulture .
the seven hylaeus species are 7–9 millimetres long , and slender . almost hairless , they are black with small yellow markings on the face and thorax . they make nests in blind tunnels in twigs and branches , or in old beetle holes in logs . they have no special pollen - carrying structure on the back legs , so carry pollen in the stomach .
the smallest ( 4–8 millimetres long ) and most easily overlooked native bees are four species of lasioglossum . they are black or greenish , only moderately hairy , and nest in the soil . at least one species , lasioglossum sordidum , has adapted well to modified habitats . its nests are often found along fencelines , on horticultural land sprayed bare with herbicides , and on stopbanks and ditch sides above water level .
all text licensed under the creative commons attribution - noncommercial 3 . 0 new zealand licence unless otherwise stated . commercial re - use may be allowed on request . all non - text content is subject to specific conditions . © crown copyright .
thank you ! there are lots of details in tiny things , and i love them .
most of our native bees don ' t quite match the perception of how a bee should look or behave . they do not form hives or live in swarms ; they generally live in burrows within the ground ; and many are relatively small and unassuming . however , they are fascinating members of our ecologies , and deserving of our attention ( particularly as they play a role in the pollination of a great number of plant species , both native and exotic ) .
the other bee that is pictured below , which i presumed to be a species of lasioglossum , was one of many native pollinators ( including a striking species of hoverfly ) that were making the most of hebe parviflora ' s abundant flowering .


the four-eyed fishes are a genus , anableps , of fishes in the family anablepidae .

they have eyes raised above the top of the head and divided in two different parts , so that they can see below and above the water surface at the same time .

like their relatives , the onesided livebearers , four-eyed fishes only mate on one side , right - " handed " males with left - " handed " females and vice versa .

these fish inhabit freshwater and brackishwater and are only rarely coastal marine .

they originate from lowlands in southern mexico to honduras and northern south america .

four - eyed fish

a
four - eyed
fish swims along the surface with eyes appearing both in and out of the water .
eye development in the four - eyed fish anableps anableps : cranial and retinal adaptations to simultaneous aerial and aquatic vision .
eye development in the four - eyed fish anableps anableps : cranial and retinal adaptations to simultaneous aerial and aquatic vision . - pubmed - ncbi
in the case of the
four - eyed fish ,
or anableps , and its sister species a . microlepis and a . dowei , the fish have two large eyes .
brenner , m . and u . krumme . 2007 - j . fish biol . 70 ( 2 ) : 406 - 427 . tidal migration and patterns in feeding of the four - eyed fish anableps anableps l . in a north brazilian mangrove .
the four - eyed name derives from the fact that it divides each pupil into two , one above the water and one below ,
lead author gregory owens told discovery news .
an anableps ' eye at the water surface . the fish actually has only two eyes , and the four - eyed name
derives from the fact that it divides each pupil into two , one above the water and one below ,
researcher gregory owens explained .
to compensate for this problem , certain other marine dwellers , such as archerfish , have to mentally calculate refraction to find the true position of objects they encounter . the
four eyed
anableps instead sees a broader angle .
one of the strangest fish in the world is anableps anableps , commonly called the ‘four - eyed fish’ because of the unique configuration of its eyes . 1 these are large and bulging , like those of a frog , and are located on the top of its head so that it swims with its eyes half in and half out of the water .
…“four - eyed fish” of the genus anableps , which cruises the surface meniscus with the upper part of the eye looking into air and the lower part looking into water . it makes use of an elliptical lens , with the relatively flat sides adding little to the power of the cornea and the…
kanungo , j . , s . k . swamynathan and j . piatigorsky . 2004 - exp . eye res . 79 ( 6 ) : 949 - 956 . abundant corneal gelsolin in zebrafish and the ' four - eyed ' fish , anableps anableps : possible analogy with multifunctional lens crystallins .
…the eye of anableps , the four - eyed fish , so named because each eye is a double structure . the eye is set high on the head and the upper part projects above the water . the cornea is divided by a horizontal band of pigment , separating an upper , strongly convex part from a…
new research explains how the fish simultaneously sees in these two very different environments .
does this fish really have four eyes ? the generic name
anableps
is derived from the greek for
up - looking .
as you can see from the picture at the left , the fish appears to be gazing meditatively upward , as though it were trying to remember how to multiply 9 x 16 .
during neap tides the fish were observed feeding on exposed areas of mud in the furo do meio .
( family anablepidae , order atheriniformes ) . four - eyed fishes are surface dwellers and have eyes adapted for seeing both above and below the water surface . the eyes are on top of the head , and each is divided into two parts , an upper half for vision in air , and a lower half for vision in water ; hence , the common name . the
the fish literally ' surf ' the peak of the flood tide into temporarily - inundated zones . . .
spiny - finned fish , any member of the superorder acanthopterygii , including four orders of marine and freshwater fishes having fins with some spiny ( as opposed to soft ) rays—atheriniformes , beryciformes , zeiformes , and lampridiformes . the atheriniform is the best known of the spiny - finned group , …
the vision system and associated over water and under water lifestyle comes at a price , though . as one might imagine , it ' s not hard for predators to miss a bug - eyed fish skimming along the surface . but anableps is forever on the lookout , with large areas of its brain devoted to vision .
homepage : urltoken facebook : urltoken twitter : urltoken + + + this is none of my own tanks . in this video you can see a fish tank of a zoo aquarium called
allwetterzoo münster
. we have videos of many tanks of this zoo . + + + the population of this tank : - largescale four - eyed fish / vierauge ( anableps anableps ) - more coming soon ( if you are intrested in helping me classifying the other species in this tank , post your suggestions ) + + + intro : 5xlmusic weitere informationen unter urltoken + + + veröffentlichung des videomaterials mit der freundlichen genehmigung des allwetterzoos münster . weitere informationen unter urltoken
four - eyed fishes are classified as order atheriniformes , suborder cyprinodontoidei , family anablepidae , genus anableps . they live in shallow , muddy freshwater streams in central america and mexico , are born live , and grow from 4–6 cm ( 1 . 5–2 . 5 inches ) at birth to 15–30 cm ( 6–12 inches ) . they usually travel in schools , cruising the surface to feed on insects and other small invertebrates . return to text .
the red and green algae upon which the fish feed during high tide is clearly visible on these mangrove stilt roots in the high inter - tidal zone .
in nature it has a diverse , but highly adapted , feeding strategy dependant on environmental conditions . at low tide it seldom forages at all except during neap tides when fish carcasses or small quantities of mud are consumed . terrestrial insects along the shoreline may also be attacked with the fish leaping onto the exposed banks .
at the waterline , the eyes are divided by a band of epithelium ( tissue ) into upper and lower parts , with separate corneas and retinas , which function for aerial and underwater vision respectively . 2 , 3 the lens is more egg - shaped than convex and can focus two images simultaneously , one from above the water and the other from below ( see diagram ) . this means that the fish’s two eyes actually function as four eyes ; hence its name .
terrestrial insects and small crabs of the family grapsidae are the other main sources of food ; these are captured by jumping attacks or the fish leaping onto the stilt roots themselves . the above water eye is actually thought to have evolved to allow the fish to exploit such high protein food sources ; for example , small crabs climb down the stilt roots to moisten their gills and the fish is able to sneak up on them before using its elongated body to launch a powerful leap . gammarid amphipods , snails , mussels and worms are also eaten in smaller amounts .
during high tides , when the fish move into inundated first order channels to feed , the majority of the diet is composed of red macroalgae ( catanella and bostrychia spp . ) which grows on the exposed mangrove stilt roots at around the average high water level . this activity is thought to be mutually beneficial as the fish perform a cleaning function which is useful to the trees in terms of growth and productivity . the water in the temporary channels is very clear compared to the turbid main channel so the fish also use the below water part of the eye to search for submerged algae and other items .
the fish does not actually have four eyes , but the eye is divided to allow the fish to see both above and below the waterline . a narrow band of epithelium divides the upper and lower halves of the eye . each half of the eye has a separate pupil , iris and cornea , but the retina is divided . both halves of the eye use the same lens , with the upper light path traveling through the short axis of the lens , while the lower light path travels through the long axis . this dual use of the lens corrects for the different behavior of light in air and in water , with the underwater lens face more strongly curved . the underwater half of the eye projects an image to the upper half of the retina , while the part of the eye above water projects to the lower retina .
the upper eye must be occasionally wetted to prevent dehydration , but when the fish is completely submerged , the image from the upper half of the eye is out of focus . click here for more information about the anableps eye .
when anableps is looking out into the air , the light rays pass through the shorter width of the lens , which gives good distance vision for locating its prey of insects ; it also means that the fish is difficult to catch , as it can see fishermen approaching ! from under the water , the light rays pass through the full length of the lens , so that the fish is near - sighted under water . 4 one is reminded of a bifocal lens in spectacles .
the researchers suspect that anableps used to just have eyes suitable for the aerial environment . over time , they think the fish lost green sensitivity in the lower eye halves , gaining yellow sensitivity there for better aquatic vision , particularly in muddy yellow water .
he said several fish , amphibians , pigeons , other birds and certain primates , including humans , all possess what is known as
intraretinal variability ,
meaning that variations in spectral sensitivity exist across the retina , which is a delicate , light - sensitive membrane lining the inner eyeball .
fish , any of more than 30 , 000 species of vertebrate animals ( phylum chordata ) found in the fresh and salt waters of the world . living species range from the primitive , jawless lampreys and hagfishes through the cartilaginous sharks , skates , and rays to the abundant and diverse bony fishes . most…
development is viviparous , with the young nourished by nutrient diffusion across the reproductive tract of the female . the fry are retained until they reach a length of about 45 mm . probably because of the size of the young fish at
birth
only 14 to 20 embryos develop from a brood . sexual maturity occurs at about 9 months .
there are three species in the genus anableps . the species found in the james r . record aquarium is anableps anableps . the genus belongs to the order cyprinodontes , small , often colorful livebearing fish with complex behaviors . the famous desert pupfish is also in this order . anableps is found in coastal waters from the yucatan peninsula to the equator .
two horizontal flaps of the iris are thought to reduce glare from the water surface . these adaptations allow the fish to see above and below the water simultaneously , and because there exists no predator which specialises on anableps the split eye is thought to have evolved specifically in order to allow exploitation of the narrow ecological niche between aquatic and terrestrial habitats .
we used in situ hybridization with opsin riboprobes to map cone opsin expression in the retina of a . anableps . this was repeated for jenynsia onca , a species with normal eye morphology in the sister genus to anableps . recently , both species have had their cone opsin repertoires characterized , revealing nine genes in a . anableps , ( one sws1 , two sws2 , two rh2 and four lws genes ) , and eight in j . onca ( one less lws gene ) [ 9 , 10 ] . by studying j . onca , we have inferred ancestral expression patterns and identified changes that have evolved in concert with the unique eye morphology of a . anableps .
inhabits brackish - water rhizophora mangrove forests where it has come to forge an extraordinary existence at the water’s edge of inter - tidal zones . these constantly fluctuating habitats are subjected to at least one , usually two , daily tidal movements and this fish has evolved to move with the water , inhabiting the shallow margins of permanent water channels during low tide and moving into inundated zones to forage when the water level rises .
for the study , owens , a university of victoria biologist , and his colleagues analyzed the eyes of the fish , focusing on light - sensitive proteins called visual opsins . each is most sensitive to a particular wavelength of light . humans , for example , have three visual opsins sensitive to blue , green and red light . they absorb light at slightly different wavelengths , enabling us to see those three colors and others .
the unique visual system allows the fish to avoid a problematic phenomenon
snell ' s window ,
which occurs when you are underwater while looking up out of the water . due to the refraction of light at the water ' s surface , after a certain angle you no longer see out of the water , and instead see a reflection on the water ' s surface . thus , your field of vision is limited to about 96 degrees .
this is supposed to mean that ‘right - sided’ males are only able to copulate with ‘left - sided’ females and vice versa . however sf members who have kept this species found that the gonopodium is flexible to a certain degree meaning it’s possible that males can mate with any partner . certainly if the former theory is true then the fish have 50 % less chance of finding a suitable partner compared with other livebearers , though perhaps they occupy such a unique ecological niche that no evolutionary bottleneck has occurred .
it’s exposed to highly variable salinity levels between 5 - 30‰ in the wild so water chemistry isn’t too much of a concern ; for ease of maintenance a specific gravity between 1 . 005 - 1 . 015 is normally recommended . apart from this the most important provision is shallow water with a depth of 15cm / 6″ or so being more than adequate ; the fish will spend almost all their time at the water surface and actually bob back up to the surface in a cork - like fashion if submerged for too long .
during low water the fish congregated in marginal zones of the main channel ( usually < 1 m away from the bank ) and the authors hypothesised that this allows them to maximise foraging time by always being close to the mouths of the temporary channels , as well as providing protection against potential predators and preventing them being swept away by strong currents in the central , deeper section . large areas of mud and sand banks are exposed during these periods and some individuals were observed to leap out of the water to lay in the sun , often for minutes at a time .
the best conditions for foraging were found to be at spring tide during daylight hours when the water level is highest and the fish are able to take full advantage of the above water eye ( see ‘notes’ ) , whereas when high tide occurred during the night less individuals were found to migrate . there is an initial rapid rise in water levels as the tide comes in and young specimens were observed swimming at the peak of the first wave to enter the marginal creeks , with adults behind . this ‘first flood rise’ was the trigger for the “virtual disappearance of a . anableps from the main channel” .
the encyclopaedia britannica describes anableps as ‘an extreme example of adaptation to life near the air - water interface’ . 5 if this is the case , how did it develop its multi - functional eyes , beginning as an ordinary fish with normal , single - function eyes ? it is extremely difficult to see how something as complex as this could develop by gradual stages , and the more parts that have to develop , the greater the difficulty . this includes the complex brain setup needed to simultaneously decode the double images being received by the two retinas . how did all this evolve until it was fully functional ?
archerfish ( toxotes chatareus ) experience a similar light environment to a . anableps and have had their vision studied using msp [ 4 ] . they were found to have double cones in the dorsal retina that were most sensitive to the most prevalent wavelengths of upwelling light . however , unlike a . anableps , double cones in the ventro - nasal retina in archerfish were shifted to even longer wavelengths , suggesting that the ventral exclusion of lws opsin expression seen in three surface - dwelling , cyprinodontiformes fish has not occurred . this implies that other features beyond light environment , such as phylogeny or the visual tasks required , may affect opsin expression .
fieldwork by brenner and krumme ( 2007 ) in the furo do meio , a tidally - influenced tributary of the caeté mangrove estuary located to the north of bragança city , 200 km south of the amazon delta , revealed that these daily migrations are entirely related to feeding ( see ‘diet’ ) . at low tide the permanent channel of the tributary measures just 30 m across , but during high water this increases to between 50 m in its upper reaches and 400 m near its mouth . smaller channels around its margins therefore become temporarily flooded and the fish move into these to forage , sometimes up to 1 km away from the main tributary .
in situ hybridization was used to characterize the topography of cone photoreceptor subtypes . anableps anableps and j . onca exhibited uniform distributions of cones expressing sws1 , sws2b and rh2 - 2 ( figure 2 and figures in the electronic supplementary material ) . neither species exhibited detectable sws2a expression in the retina . species - specific differences were noted for the rh2 - 1 - expressing cones . in j . onca , rh2 - 1 had uniform expression across the retina in all sections , whereas adult a . anableps had rh2 - 1 in a large number of ventral cone cells and in a small patch of cones at the dorsal tip of the retina . this pattern was observed in all adults . in juveniles , rh2 - 1 expression was confined to a smaller number of cells in the ventral half of the eye , or was entirely absent . the lws riboprobe , which was designed to bind all lws paralogues , revealed inter - individual and interspecific differences in lws cone photoreceptor distributions . in j . onca , lws - expressing cones were limited to the dorsal retina in two fish ( a male and a female ) and to a transverse streak in the middle of the eye in one male . in a . anableps , lws cones were detected only in the dorsal half of the retina . this pattern appears to be the inverse of the rh2 - 1 cone distribution ( figure 1 ) .
[ hd ] tank of the giants : 13200 us gallon / 50 . 000 liter landschafts - aquarium @ aquazoo [ 7 / 52 ]
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the findings , published in the latest royal society biology letters , help to explain how animal visual systems , including human ones , evolve in response to different light environments .
the scientists determined that the top part of anableps ' eyes , the set that sticks out of the water , possess opsins sensitive to green . the bottom half of the eyes , actually in the water , are sensitive to yellow . the entire eye has genes sensitive to ultraviolet , violet and blue light .
this tells us that anableps is more sensitive to yellow light from the water and green light from the air ,
owens said .
we hypothesize that this functions to match their sensitivity with the light available . the water anableps lives in is generally muddy ( mangrove forests of northern south america ) and in this muddy water yellow light transmits best .
all lightning on earth may have its roots in space , new research suggests .
karen carleton , an assistant professor in the university of maryland ' s department of biology , told discovery news that
what dr . owens and his colleagues are seeing is quite reasonable .
she said
it seems probable that anableps has
fine tuned
its eyes
for its two visual tasks .
shelby temple of the university of bristol ' s visual ecology group also supports the new findings , saying that they have
added yet another example of a vertebrate that has the potential to have different spectral sensitivity in different parts of its field of view .
temple concluded ,
now we just need to try and understand why so many animals may be sensitive to different wavelengths of light in different directions .
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anableps seems to be designed for asymmetrical mating . in females , a single large scale covers the cloaca and opens either to the left or to the right . in males , the anal fin is adapted as a funnel for sperm transfer , and similarly extends either to the right or the left of the body .
fertilization is internal , and males and females have to be appropriately matched . right - handed males outnumber left - handed males about 60 : 40 with about the same proportion of the appropriately structured females .
anableps is primarily a surface feeder and its view of surface activity makes it difficult to catch , except with long - handled nets .
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( ed . ali , m . a . ) 609–617 ( plenum , new york , 1975 ) .
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comparison of anablepid eye morphology . ( a ) a . anableps eye at the water surface . the dorsal cornea receives light from the aerial environment , while the ventral cornea receives light from the aquatic environment . dc , dorsal cornea ; vc , ventral cornea . photo by andreas werth . ( b ) jenynsia onca female . the eye is morphologically normal in this species . photo by leo van der meer . ( c ) a schematic of a sagittal section of an a . anableps eye . light paths are indicated . green and yellow dots indicate rh2 - 1 and lws gene expression , respectively . ael , aerial line - of - sight ; aql , aquatic line - of - sight ; l , lens ; on , optic nerve ; dt , dorsal tip of the retina ; d , dorsal retina ; m , medial retina ; v , ventral retina . ( d ) in situ hybridization images of adult a . anableps labelled with the rh2 - 1 or lws riboprobe . cone cells expressing the gene of interest are purple . the brown area is retinal pigment epithelium .
summary of expression domains for each gene tested in a . anableps and j . onca . ( a ) the visual spectrum as seen by humans with putative spectral sensitivity for each opsin tested . numbers are in nanometres . ( b ) schematic of eyes with dorsal on top , ventral on bottom . coloured areas indicated expression , while dotted bars indicated areas of polymorphic expression . cropped microscope images are retinal sections probed using each riboprobe . cone cells expressing the gene of interest are purple .
anableps anableps ' remarkable eyes simultaneously sample photons from terrestrial and aquatic habitats . in situ hybridization with six riboprobes demonstrated that a . anableps and the closely related j . onca express at least five cone opsins ( sws1 , sws2b , rh2 - 1 , rh2 - 2 and lws ) , possibly more given the redundancy of our lws probe .
the wavelength of maximal sensitivity for a visual pigment ( and consequently the photoreceptor expressing it ) can be determined by microspectrophotometry ( msp ) or in vitro protein reconstitution [ 13 , 14 ] . by comparing maximal sensitivity data from a . anableps and its relatives obtained using these techniques , we have endeavoured to assign specific opsin genes to cone cell spectral sensitivities : sws1 ( 356–365 nm , uv ) , sws2b ( 405–425 nm , violet ) , rh2 - 2 ( 452–472 nm , blue ) , rh2 - 1 ( 492–539 nm , green ) and lws ( 543–576 nm , yellow ) ( figure 2 a and discussed in supplementary materials ) . while these represent the value for individual opsin proteins , multiple proteins may be found co - expressed in a single cone , causing intermediate sensitivity values for the photoreceptor .
early msp work showed no difference in the prevalence of different cone cells between retinal halves [ 15 ] . however , our in situ hybridization experiments , which are better suited to assess photoreceptor distributions because they sampled more photoreceptors by several orders of magnitude , did detect differences : the dorsal retina , used for aquatic vision , has cone photoreceptors that express sws1 , sws2b , rh2 - 2 and lws , while the ventral retina , used for aerial vision , expresses sws1 , sws2b , rh2 - 2 and rh2 - 1 ( figure 2 ) . from these observations , we predict that wavelength sensitivity differs in the dorsal and ventral regions of the retina .
the reduction of rh2 - 1 expression and retention of lws expression in the dorsal retina suggest that a . anableps has enhanced sensitivity to long wavelength light ( 543–576 nm ) in the aquatic field of view . this enhanced sensitivity could be advantageous in the brackish waters of the mangrove forests and river deltas that a . anableps inhabits , as these often contain dissolved organic matter that shifts light abundance to longer wavelengths [ 17 ] . light measurements taken in similar mangrove habitat showed that downwelling light is most prevalent at approximately 500 nm , while upwelling light peaks at approximately 580 nm [ 4 ] . we propose that , by the differential expression of rh2 - 1 and lws , a . anableps is better able to match its double cones to the background light in each field of view .
we thank three anonymous reviewers for helpful suggestions . we were supported by nserc discovery grants ( j . s . t . ) and graduate scholarship ( g . l . o . ) , as well as university of victoria graduate fellowships ( g . l . o . and d . j . r ) . we thank the university of victoria advanced imaging centre for their assistance .
switch in rod opsin gene expression in the european eel , anguilla anguilla ( l . )
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this configuration of the eyes enables anableps to search for food in one habitat ( air ) and at the same time watch out for predators in another habitat ( water ) . when it sees a predator approaching through the water , it escapes by leaping out of it , which is a reason why this species is not very suitable for keeping in a small home aquarium . another unusual habit is that when swimming it continually ducks its head under the water . this is because , unlike most land animals , it does not have a tear duct to keep the eye moist and so must duck to prevent its eyes from drying out .
) . this accounts for the formation of all the parts of the eyes and the needed complementary parts of the brain , with everything functional from the beginning .
‘the cornea is divided by a horizontal band of pigment , separating an upper , strongly convex part from a lower , flatter division . the iris has a pair of projections , partially dividing the pupil into two . ’ encyclopaedia britannica , 19 : 252 , 1992 . see also ibid 1 : 668 . return to text .
using a camera as a rough analogy , we can think of the cornea as the ‘window’ in front of the lens , and the retina as the surface on which the image is focused , somewhat like the film in a camera . from there , electrical signals send this visual information to the brain , where the signals are processed into mental images . return to text .
edward migdalski and george fichter , the fresh and salt water fishes of the world , bay books , sydney , australia , 1976 , p . 186 . return to text .
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atheriniform , any member of the order atheriniformes , containing 15 families of marine and freshwater spiny - finned fishes , including the flying fishes ( see photograph ) , needlefishes , silversides , and cyprinodonts . the last group , the cyprinodontidae , is an abundant tropical and subtropical family…
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animal , ( kingdom animalia ) , any of a group of multicellular eukaryotic organisms ( i . e . , as distinct from…
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perez ln 1 , lorena j 1 , costa cm 1 , araujo ms 1 , frota - lima gn 1 , matos - rodrigues ge 2 , martins ra 2 , mattox gm 3 , schneider pn 4 .
instituto de ciências biológicas , universidade federal do pará , belém , pará , brazil .
instituto de ciências biomédicas , universidade federal do rio de janeiro , rio de janeiro , brazil .
departamento de biologia , universidade federal de são carlos , campus sorocaba , são paulo , brazil .
instituto de ciências biológicas , universidade federal do pará , belém , pará , brazil schneider @ ufpa . br .
pmid : 28381624 pmcid : pmc5394668 doi : 10 . 1098 / rspb . 2017 . 0157
the anableps eye . ( a ) anableps anableps adult female specimen . ( b ) close - up view of the a . anableps eye ; dorsal and ventral corneas and pupils are visible . ( c ) schematic of the visual aerial and aquatic inputs ( sagittal view of the eye ) . rpe , retinal pigmented epithelium ; onl , outer nuclear layer ; inl , inner nuclear layer ; gcl , ganglion cell layer ; on , optic nerve ; dr , dorsal retina ; dp , dorsal pupil ; vr , ventral retina ; vp , ventral pupil ; ch , choroid ; l , lens ; ir , iris ; ps , pigmented strip ; dc , dorsal cornea ; vc , ventral cornea ; do , dorsal ; ve , ventral ; di , distal ; pr , proximal . scale bars : 1 cm ( a ) , 0 . 5 cm ( b ) .
eye development during larval stages . anableps anableps larvae at stage 1 ( a , b ) , stage 2 ( c , d ) , stage 3 ( e , f ) , stage 4 ( g , h ) , stage 5 ( i , j ) and stage 6 ( k , l ) . figures to the right are higher magnification images of ocular region . scale bars : 5 mm ( a , c , e , g , i , k ) , 500 µm ( b , d , f , h , j , l ) .
neurocranium ontogeny . anableps anableps neurocranium at stage 3 ( a , b ) , stage 4 ( c , d ) , stage 5 ( e , f ) stage 6 ( g , h ) and in the adult ( i , j ) . panels show dorsal ( left ) and lateral ( right ) views . boc , basioccipital ; epbar , epiphyseal bar ; epo , epiotic ; epopr , epiotic process ; ethpla , ethmoid plate ; exoc , exoccipital ; fro , frontal ; intsp , interorbital septum ; lamorb , lamina orbitonasalis ; let , lateral ethmoid ; mfl , membranous flap ; otcap , otic capsule ; par , parietal ; pro , prootic ; pto , pterotic ; psph , parasphenoid ; soc , supraoccipital ; sph , sphenotic ; tm , taenia marginalis ; trcom , trabecula communis ; the frontal and the interorbital septum are denoted in bold . scale bars : 1 mm .
= 5 , mean and standard deviation were calculated for a total of 27 eye sections ) . (
= 2 ; biological replicates for each larval stage of development ) . dr , dorsal retina ; vr , ventral retina ; l , lens ; ir , iris ; ps , pigmented strip ; dc , dorsal cornea ; vc , ventral cornea ; rpe , retinal pigmented epithelium ; is , inner segments ; os , outer segments ; onl , outer nuclear layer ; opl , outer plexiform layer ; inl , inner nuclear layer ; ipl , inner plexiform layer ; gcl , ganglion cell layer . scale bar : 200 µm .
asymmetric opsin gene expression in the larval retina . ( a ) analysis of the pattern of expression of five visual opsins in ventral retina , relative to the dorsal retina , as determined by qpcr . the relative expression values were determined using the 2 −δδct method . bars represent mean in log 2 scale ±standard deviation of biological and technical replicates ( n = 9 ; three biological and three technical replicates ) . student ' s t - test was used to assess statistical significance between samples ( * * p < 0 . 01 and * * * p < 0 . 001 ) . ( b – k ) in situ hybridizations of visual opsins in eye sections of larvae of a . anableps : rh1 ( b , c ) , rh2 - 1 ( d , e ) , rh2 - 2 ( f , g ) , sws2b ( h , i ) and lws ( j , k ) . left column shows expression pattern in portions of the dorsal retina , as well right column in the ventral retina . scale bars : 0 . 05 mm . ( l – o ) immunofluorescence assay showing opsin expression on the dorsal and ventral retina in a . anableps at stage 6 . ( l , m ) immunostaining showed that rhodopsin is expressed equally in the dorsal and ventral retina . ( n ) opsin l / m monoclonal is only expressed in the dorsal retina . ( o ) opsin l / m monoclonal expression is not detected on the ventral retina . onl , outer nuclear layer ; inl , inner nuclear layer ; gcl , ganglion cell layer . cryosections are 20 µm thick . scale bars : 50 µm ( b – k ) and 200 µm ( l – o ) .
female of a . anableps . the pale stripe running down the dorsal surface is an identifying feature for this species .
the furo do meio is a tidal tributary of caeté bay , brazil and a typical habitat of this species .
. . . whereas during low tide they typically congregate in large groups . this and the previous image were taken off the coast of suriname .
a . anableps during low tide in the main channel of the furo do meio .
occurs along much of the north - east south american coastline from the gulf of paria ( the shallow , brackish inland sea which separates trinidad and tobago from venezuela ) through guyana , suriname and french guiana and past the amazon delta in brazil as far as the parnaíba river estuary at the border between the states of maranhão and piauí .
sympatric species in the furo do meio included colomesus psittacus , sciades herzbergii , pseudauchenipterus nodosus and hyporhamphus roberti .
surface area is far more important than height but this species is unsuitable for all but the largest aquaria ; a tank with base dimensions of 150 cm x 45 cm should be the minimum considered , and even this could only house half a dozen adults at most . given that it’s known to congregate in large groups at low tide , often comprising several hundred individuals , it’s clearly more suited to public than private aquaria .
temperature : strictly a tropical species ; the temperature should be maintained between 25 – 31 °c .
in captivity most dried foods are accepted but should not form the principal component of the diet , and it’s best to use a product with added spirulina or similar . gut - loaded drosophila fruit flies , bloodworm , artemia and chopped earthworms are excellent treats and good results have been reported using a home - made , gel - based recipe containing a mixture of seafood and fresh vegetables . feed twice daily to mimic its natural feeding cycle and note that a poor diet may be associated with reproductive problems ( see ‘breeding’ ) .
best kept in a species - only display and may predate on much smaller fishes but in very large tanks can be combined with peaceful estuarine fishes . some poecilia spp . are suitable and if geography is ignored monodactylus and bottom - dwelling gobies such as stigmatogobius sadanundio are possibilities . avoid vigorous surface - dwellers such as toxotes spp . or voracious feeders like scatophagus as this species has no natural competitors .
it should be maintained in a group of at least six , preferably a dozen or more as it can behave nervously in the absence of conspecifics . aggression is rare except in gravid females ( see ‘breeding’ ) .
females grow considerably larger than males and the latter possess a prominent gonopodium . this has a different structure to that seen in poeciliid livebearers having a scaled , tubular structure .
anableps species are viviparous and mating usually presents few problems provided you have a mixed - sex group . the genital opening of the female is covered by a hinged flap of skin known as the foricula , and most aquarium literature suggests that both this and the gonopodium of the male are naturally - orientated to the left or right depending on the individual .
gestation takes around 12 weeks and the female’s appetite increases significantly during this period . just before giving birth she becomes hostile towards any other tankmates and will attempt to find a quiet spot to release the young . these are fully - formed , measure around 40 - 50mm and are able to accept quite large morsels of food immediately .
many breeders have experienced problems with young being born prematurely , often with sections of the gut protruding through an opening in the abdomen . this leaves them susceptible to infection but in some cases they can be saved via removal them to a separate tank containing sterile water . it’s unknown whether such issues relate to water quality , diet , sexual maturity or stress but we’d suggest isolating gravid specimens and offering a varied diet containing both high protein items and algae .
the eye of anableps species is split horizontally by a band of epithelial tissue . it has two corneas , two pupils , a single , egg - shaped lens and one retina that’s also split into two sections . the lens is oval and asymmetric with the upper part flattened as in the human eye and the lower section curved as in most other fishes . the upper cornea is thicker and enriched with glycogen which possibly helps to protect it from drying and uv irradiation .
the family anablepidae also includes the genera oxyzygonectes ( monotypic ) and jenynsia ( 13 species ) . they’re members of the order cyprinodontiformes so are related to killifish , goodeids and poeciliid livebearers . anableps is the only genus to have developed specialised eye morphology and but jenynsia species are also viviparous .
ghedotti , m . j . and e . o . wiley . 2003 - in : carpenter ( 2003 ) . the living marine resources of the western central atlantic . v . 2 . anablepidae .