the dwarf seahorse ( hippocampus zosterae ) is a species of seahorse found in the subtidal aquatic beds of the bahamas and parts of the united states .

it is threatened by habitat loss .

according to guinness world records , it is the slowest moving fish , with a top speed of about 152 centimetres per hour .

it is most often white in color but can range from tan , brown , yellow and green .

in the wild , it often has small skin growths called cirri that resemble algae .

dwarf seahorse

dwarf seahorse <EOT> noaa fisheries . dwarf seahorse ( hippocampus zosterae ) . accessed september 30 , 2014 .

genetic evidence for monogamy in the dwarf seahorse , hippocampus zosterae . - pubmed - ncbi

information on the dwarf seahorse is currently being researched and written and will appear here shortly .

as “data - deficient , ” meaning that no one has really looked into the dwarf seahorse’s population dynamics .

the dwarf seahorse ( hippocampus zosterae ) is a small seahorse found in the western atlantic ocean . they are also known as little seahorses or pygmy seahorses .

masonjones , h . , s . lewis . 1996 . courtship behavior in the dwarf seahorse , hippocampus zosterae .

zebra snout seahorse hippocampus barbouri , a beautiful seahorse but one that frequently does poor in captivity .

masonjones hd and sm lewis . 1996 . courtship behavior in the dwarf seahorse , hippocampus zosterae . copeia 1996 : 634 - 640 .

embed this arkive thumbnail link ( " portlet " ) by copying and pasting the code below . < a href = " urltoken " title = " arkive photo - dwarf seahorse dorsal view " > < img src = " urltoken " alt = " arkive photo - dwarf seahorse dorsal view " title = " arkive photo - dwarf seahorse dorsal view " border = " 0 " / > < / a >

embed this arkive thumbnail link ( " portlet " ) by copying and pasting the code below . < a href = " urltoken " title = " arkive species - dwarf seahorse ( hippocampus zosterae ) " > < img src = " urltoken " alt = " arkive species - dwarf seahorse ( hippocampus zosterae ) " title = " arkive species - dwarf seahorse ( hippocampus zosterae ) " border = " 0 " / > < / a >

embed this arkive thumbnail link ( " portlet " ) by copying and pasting the code below . < a href = " urltoken " title = " arkive photo - adult male dwarf seahorse with young " > < img src = " urltoken " alt = " arkive photo - adult male dwarf seahorse with young " title = " arkive photo - adult male dwarf seahorse with young " border = " 0 " / > < / a >

project seahorse is the world’s premier seahorse conservation and research organization . a wealth of information is available at their web site : urltoken

jordan , , gilbert . 1882 . " hippocamous zosterae ( dwarf seahorse ) " ( on - line ) . fishbase . accessed october 13 , 2004 at urltoken .

video : " dwarf seahorse snatches a copepod " check out this up - close - and - personal video showing how these tiny seahorses can be deadlier than sharks .

we set out to catch a modern day unicorn , the dwarf seahorse , as dainty and secretive a creature as you can find anywhere on land or under the sea .

in fact , the center for biological diversity filed a petition in 2011 to list the dwarf seahorse under the endangered species act . federal officials are still considering that petition .

soon after the deepwater horizon oil spill , the center leapt into action to fight dangerous offshore oil drilling that threatens the survival of the dwarf seahorse and countless other animal and plant species . a year later , with pollution still persisting in the gulf and the seahorse in dangerous decline , we filed a scientific petition to federally protect the species . in 2012 , the national marine fisheries service announced that the dwarf seahorse may warrant protection .

dwarf seahorses have 9 - 10 bony rings around their trunk and 31 - 32 rings around their tail .

the small size and specific body ring and dorsal ray counts should be sufficient to allow the dwarf seahorse to be distinguished from the larger congener hippocampus erectus , with which it may co - occur .

full , round belly . a healthy seahorse is a will feed seahorse . while they tend to be fairly thin by nature , any caved in sides is a bad sign .

" hi there , i have 9 dwarf seahorses in a 35 gallon bow front . the tank is . . . "

vincent , a . 1995 . a role for daily greetings in maintaining seahorse pair bonds .

are humans . dwarf seahorses are extremely popular in the aquarium trade because of their small size . some fisheries off the coast of florida have built their business around the capture of live dwarf seahorses in shallow grass beds for the aquarium trade . tens of thousands of

the marine curio industry also affects wild seahorse populations . for more about this threat , go to

the seed to go on a seahorse hunt was planted during a recent conversation with brian jones of the sea lab , who mentioned that the lab had acquired some dwarf seahorses from another facility and would be putting them on display .

high reproductive rates and a stable population size suggest dwarf seahorses are an important trophic link in halodule seagrass communities ( strawn 1958 ) .

the breeding season for dwarf seahorses runs from february to november . in captivity , these animals have been reported to mate for life .

hermit crabs are not very effective predators in general , but a very large individual might be able to overcome a dwarf seahorse . it’s more likely that the crab was scavenging an already dead seahorse , but stick to very small individuals in your tank . these should be quite easy to collect in the waters inhabited by the pipefish .

, commonly known as the dwarf seahorse , inhabits coastal waters of the western atlantic ocean , including the caribbean sea , the gulf of mexico , and the continental shelf of the southeastern united states ( jordan and gilbert , 1882 ) .

dwarf seahorses are also collected in florida for the marine ornamental aquarium industry . annual seahorse landings vary widely , but adams et al . ( 2001 ) indicates more than 80 , 000 h . zosterae were collected in florida in 1992 .

masonjones , h . 2001 . the effect of social context and reproductive status on the metabolic rates of dwarf seahorses ( hippocampus zosterae ) .

dwarf seahorses , hippocampus zosterae remains an ever popular , easy to care for aquarium pet . the basics of keeping them are . . .

bright , active eyes . a healthy seahorse will swivel its eyes around in constant search of food .

citation : fedrizzi n , stiassny mlj , boehm jt , dougherty er , amato g , mendez m ( 2015 ) population genetic structure of the dwarf seahorse ( hippocampus zosterae ) in florida . plos one 10 ( 7 ) : e0132308 . urltoken

a pair of dwarf seahorses are entombed in this acrylic paperweight bought in a seashell curio shop . thousands of seahorses meet a similar fate every year .

large species of seahorse , very similar to h . reidi in form and coloration . a subtropical seahorse from the pacific , found on the west coast , possibly as far north as california . outgoing , active seahorse . but very difficult to keep successfully . prone to bacterial illnesses that tend to then infect any other syngnathid inhabitants .

your fears are correct . seahorse should not be kept with reef lobsters . please look at the tankmates article .

breeding interval dwarf seahorses remate within 4 to 20 hours after the young have been released from the brood pouch . this may occur throughout the breeding season .

for those who have never seen a pipefish , it is the closest swimming relative of the seahorse . in fact , pipefish look just as a seahorse would look if you straightened its body out and bent the seahorse head to be in line with the rest of the body . but they share a much more fascinating trait than just appearance .

the trade in dwarf seahorses for both the aquarium and curio trades has historically been concentrated in florida [ 51 , 52 ] . collection of h . zosterae in florida is regulated in the same manner as other near - shore marine fishes and is subject to the restrictions of recreational and commercial fishing licenses issued by the florida fish and wildlife conservation commission [ 51 ] . the results of our analyses , considered alongside observations of the methods of dwarf seahorse collectors , suggest that the impact of the aquarium trade on h . zosterae is likely small and can be sustained by dwarf seahorse populations . implementation of seasonal restrictions on large - scale catches of dwarf seahorses , such as those for the curio trade , could be a useful management tool for curtailing collection during the peak of annual population contraction , which occurs from december to february [ 1 , 52 ] .

staring at a picture of a dwarf , i thought , what a thing , to catch one of these tiny and magical creatures and hold it in your hand . in a lifetime spent prowling ocean waters , i had previously encountered only one live seahorse , which my cousin mike and i caught in a seine in panama city in the 1970s . it was the more common and much larger lined seahorse .

a 10 gallon aquarium is far too small for most seahorse species , and clownfish are not good tank mates for seahorses .

the key to feeding dwarf seahorses dwarf seahorses are one of the only seahorse species that will thrive on a diet consisting solely of enriched brine shrimp . they will , however , appreciate an occasional meal of tiny , wild caught invertebrates – thin meshed “plankton nets , ” ( available from biological supply houses ) drawn through shallow marine waters will yield a wealth of valuable food items . “enriched” brine shrimp are those that have been allowed to feed for a few days before themselves being given to the seahorses . this process increases the shrimps’ nutritional value , and is indispensable if one is to succeed in keeping dwarf seahorses . therefore , brine shrimp intended as seahorse food should be given brightwell aquatic’s phyto - green , or a similar product , for several days .

2003 . " biology of seahorses " ( on - line ) . project seahorse . accessed october 13 , 2004 at urltoken .

tiger tail seahorse , hippocampus comes , showing the distinctive tail coloration that earned this species it’s name . photo courtesy of debby ng

one issue that new seahorse keepers struggle with is what exactly they need for an aquarium setup to keep seahorses . . . .

the two species highlighted in this article ( please see part i , the atlantic seahorse , published last week ) were chosen because , of all , they are the most likely to do well on diets that are within the means of most aquarists . please do not be tempted to try other species until you are well - experienced with the following animals . i will focus here on points unique to seahorse husbandry – water quality and filtration should be managed as for other marine fishes ( please see related articles posted on this blog ) . dwarf seahorse , hippocampus zosterae

the male seahorse carries fertilized eggs in his " brood pouch " for 9 to 45 days until the young seahorses emerge fully formed .

great info…i’ve always been interested in keeping a seahorse tank , but haven’t had much time . my reef tanks keep me busy enough !

we had a few local hermit crabs as you suggested in the book , but found one eating a seahorse , and so released them just to be on the safe side . could the hermit crab have killed the seahorse ? sorry for so many questions , thank you .

as it stands , dwarf seahorses are the second most popular fish exported from the state for the aquarium trade , with reports of tens of thousands sold live each year . still , collection for the chinese market takes the lion ' s share of all seahorse species internationally . a guide to the identification of seahorses , a 2004 scientific paper about the status of global seahorse populations , states that the asian trade exceeds 50 tons of dried seahorses a year , a stunning amount considering how small even the largest seahorse species are . the international union for conservation of nature , which publishes the iucn red list of threatened species , considers all 30 - plus known seahorse species to be in danger of extinction due to exploitation and habitat loss .

throughout their range , using a variety of gear types and inconsistent sampling frequencies and duration ' s . throughout this section , reported seahorse densities are low , but this has been observed broadly across seahorse species ( foster and vincent 2004 ) and is strongly related to gear specificity in

seahorses ' unique life - history characteristics and habitat specificity make them particularly vulnerable when faced with exploitation and habitat degradation . seahorses have elaborate social and reproductive behaviors , with males giving live birth and partners forming monogamous bonds that are reinforced each morning with a greeting ritual . the imperiled dwarf seahorse is too special to abandon to extinction .

a mated pair ! dwarf seahorses are known to be monogamous , and to mate for life . their elaborate courtship rituals are well documented . and here was a mated pair basically holding hands .

and other seahorse species produce a rapid clicking sound as a form of communication . these clicking sounds have been observed during courtship and copulation , inter - male competition , feeding , and stress produced , for example , by moving a seahorse from one tank into another . dwarf seahorses produce these clicking sounds by stridulation , which is the production of sound through the grinding together of hard , usually bony structures . in this case the skull grinds against the vertebrae . more specifically ,

most of the harvest occurs in the grass beds of south florida , which appear to be the dwarf seahorse ' s last remaining stronghold . the state of florida recently rejected recommendations from a state panel that sought to beef up the rules governing the harvest . the rule change would have cut the number that could be harvested in a day from 400 to 200 per boat , set a limit of 25 , 000 per year for the annual harvest , and prohibited collecting dwarf seahorses anywhere but within this stronghold area . some scientists believe the seahorse populations in other parts of the state have been affected by years of heavy collection and shrimp trawling , nearly wiping them out from some areas .

well that depends on the seahorse you’re interested in . typically the larger and more brightly colored individuals cost more than the smaller and duller colored ones

bloating . while a fat seahorse is a healthy seahorse , they also succumb to infections that cause fluid to accumulate under the skin . it can be difficult to tell the difference in the early stages , but one thing you can do is watch for if it is still eating or not .

while this just a basic overview of what is needed for keeping seahorses , following these three keys will lead to a happy , healthy seahorse tank .

many middle - aged and older aquarists may be familiar with dwarf seahorses , even if they don’t realize it . those of us who grew up in the precomputer age reading comic books are likely familiar with the ads in the back of those comic books offering seahorses for sale . these were dwarf seahorses , and those of us who bought them had live fish arriving in the mail years before the internet began .

the maximum length of a dwarf seahorse is just under 2 inches . like many other seahorse species , it has a variety of color forms , which range from tan to green to almost black . their skin may be mottled , have dark spots , and covered in tiny warts . these seahorses have a short snout , and a coronet on top of their head that is very high and column - like or knob - like in shape . they may also have filaments extending from their head and body .

as early as the mid - 1950s , dwarf seahorses were preserved , dried , and sold to shell dealers for $ 15 . 00 to $ 25 . 00 per 1 , 000 ( strawn 1954 ) .

baum jk , vincent acj ( 2005 ) magnitude and inferred impacts of the seahorse trade in latin america . environ conserv 32 ( 4 ) : 305–319 .

after reading this , are you thinking of setting up your own seahorse aquarium ? stop by our forums to ask any questions you have about keeping seahorses .

dwarf seahorses are precocious and will breed freely in captivity . some seahorse species are reported to be monogamous , but dwarfs definitely like to play the field . i have one large female that mates on a regular basis with at least four different males . their mating dance usually happens early in the morning , and i’ve never seen a pair mate in the afternoon or evening .

dwarf seahorses eat small crustaceans and tiny fish . like other seahorses , they are " ambush predators , " and use their long snout with a pipette - like motion to suck in their food as it passes by .

vincent , a . 1997 . " nova - kingdom of the seahorse " ( on - line ) . pbs . accessed october 13 , 2004 at urltoken .

project seahorse 2003 . hippocampus zosterae . the iucn red list of threatened species . version 2014 . 2 . < urltoken > . accessed september 30 , 2014 .

seahorse keepers are obsessed with food . live food , dead food , big food , small food . why ? because our seahorses are so dependent on it .

" the dwarf seahorse ' s mating ritual is fascinating , " said mccawley , with the florida fwc . it is " marked by distinct behavior changes and intensity and occurs over 3 - 4 days . the phases include side - by - side vibrating or quivering , showing bright and / or rapid color changes , head pointing , and repeatedly rising together in the water column . "

with adults only about an inch tall , the dwarf seahorse is the smallest of the four seahorse species found in u . s . waters . this dainty , curly - tailed fish occurs only in shallow seagrass areas in the gulf of mexico , along the atlantic coast of florida and in the caribbean . unfortunately , this seahorse now faces numerous threats to its existence , and the best available science shows that it ' s in decline . widespread loss of the species ' seagrass habitat due to pollution , damage from boats and trawls and global warming is hurting the minuscule creature — which is further endangered by collection for use in the aquarium trade , as curios , and for prepackaged traditional medicines . after the catastrophic 2010 gulf of mexico oil spill degraded much of its range , this seahorse is more threatened than ever and could disappear forever without the protection of the endangered species act .

strawn k . 1958 . life history of the pigmy seahorse , hippocampus zosterae jordan and gilbert , at cedar key , florida . copeia 1958 : 16 - 22 .

lourie s ( 2003 ) fin - clipping procedure for seahorses . in : project seahorse technical bulletin 3 . fisheries centre , university of british columbia , pp 1–4 .

reidi are available in australia by the only remaining commercial breeders here seahorse australia . urltoken just expensive and only seems to be females at the time of this comment .

is one of the smallest of the many different seahorse species , ranging in size between 2 to 2 . 5 cm . the maximum reported size was a male of 5 . 0 cm ( jordan and gilbert , 1882 ) . this species of seahorse can be distinguished from other western atlantic seahorse species by the presence of 10 to 13 dorsal and pectoral fin rays ( daswon and vari , 1982 ) . also , dwarf seahorses possess 9 to 10 trunk rings , a high knob - like coronet that lacks spines or projections , knob - like spines on the body , a short snout that is one - third the length of the head , and skin covered in tiny warts ( lourie et al . , 2004 ) .

lourie s , foster s , cooper e , vincent ac ( 2004 ) a guide to the identification of seahorses . traffic north america and project seahorse , washington dc .

the dwarf seahorse , hippocampus zosterae , is a small seahorse common to florida seagrass flats . it is variable in color , often tan and unpatterned , but individuals can also range in color from green to nearly black . the snout is long relative to body size and the coronet ( head projection ) is high and knob - like . the dorsal fin has 11 - 13 fin rays and a dark submarginal stripe that may aid in identification . body ring counts reveal 10 - 14 trunk rings and 31 - 33 tail rings ( hoese and moore 1977 , robins et al . 1986 ) .

chang ch , lin hy , jang - liaw nh , shao kt , lin ys , ho hc . ( 2013 ) the complete mitochondrial genome of the tiger tail seahorse ,

goswami m , thangaraj k , kumar b , chaudhary l , bhaskar sk , gopalakrishnan a , et al . ( 2009 ) genetic heterogeneity of the indian stocks of seahorse (

an ideal “first seahorse” in sharp contrast to larger fishes , dwarf seahorses offer us the opportunity to observe nearly all of their natural behaviors in captivity . due to their small size , they adjust readily to the confines of aquarium life . three pairs in a 15 gallon tank will reward you with a display of activities not often observed among captive seahorses of other species . as a consequence , their captive husbandry is well understood , and many specimens in the trade are commercially produced . this is an important consideration at a time when many seahorse species are in sharp decline ( please see below ) .

the size and shape of the aquarium is also important to seahorse health . 20 gallons per seahorse is the absolute minimum for a pair of seahorses . 40 gallons per pair of the really large species such as h . ingens or h . abdominalis . however , water volume is only one factor when determining the best size seahorse aquarium . seahorses need tall aquariums , as they are vertical swimmers . this is especially true if you plan to breed them . minimum tank size is three times the total adult height of the seahorse . be sure this is after you subtract the depth of your sand bed . a 20 - inch tank with a 6 inch sand bed only gives seahorses 14 inches of usable height .

our results support an isolation by distance model as a contributing driver of population structuring in floridian h . zosterae , in which geographically proximate populations are more genetically similar than those that are farther apart [ 36 ] . these findings implicate a stepping - stone or nearest - neighbor model in the structuring of dwarf seahorse populations , though other organismal and environmental factors are likely influential , including rafting and current patterns [ 39 ] .

overwintering cedar key dwarf seahorses disappear from the grass flats by early august and do not become member ' s of the next year ' s overwintering population . strawn ( 1958 ) suggested that individuals from this population rarely exceeded one year in age .

description and habitat “seapony” might be a more appropriate name for this diminutive creature , which , at an adult length of 0 . 9 inches , is only slightly larger than the smallest known species , denise’s pygmy seahorse ( please see below ) . ranging from florida to the bahamas , the dwarf seahorse may be white , yellow , green or black in color . it dwells in sea grass beds , so much so that the species name , “zosterae” , is drawn from that of the plant with which it is most often associated . northern populations were formerly considered to be a separate species , h . regulus .

driving home , this thought occurred to me regarding the fact that they mate for life : if i were only able to move five feet an hour and i managed to find another of my species in a huge forest of grass , and that one i found was the opposite sex , i ' d probably never let her out of my sight either . especially so if she looked as lovely and delicate as a dwarf seahorse .

was listed in 2000 as vulnerable on the iucn red list of threatened species . one major threat to dwarf seahorses is habitat degradation due to extraction from subsistence , artisanal uses , and large - scale fisheries as well as infrastructure development such as industry , human settlement , and tourism . harvesting for local , national , and international trade and accidental mortality as bycatch in fishing nets are also threats to this population . due to the small size of dwarf seahorses , they are popular in the aquarium trade .

boehm jt , woodall l , teske pr , lourie s , baldwin c , waldman j , et al . ( 2013 ) marine dispersal and barriers drive atlantic seahorse diversification . j biogeogr

i’m often asked which species of seahorse aquarists should get for their first aquarium . this question may sound simple enough , but different species behave differently and have varying levels of care required .

also has a dorsal fin with a submarginal band ( dawson and vari , 1982 ) . dwarf seahorses are found in colors of beige , yellow , green , and black , and may have white speckles or dark spots ( lourie et al . , 2004 ) .

( 1989 ) , observing 0 . 37 animals / m² in 1994 / 1995 combined , again showing that across habitat types , seahorse densities were stable . using otter trawls in deeper areas , thayer

as a testament to their hardiness , most of those early shipments arrived alive and well . because the dwarf seahorse is relatively easy to care for , provided a few basic needs are met , those of us who followed the simple directions that came with them were rewarded with fish that often reproduced and survived for several generations in our care . unfortunately , i’m sure many others did not follow those directions , and those poor fish in their care did not last long .

dwarf seahorses live in shallow waters populated with seagrasses . in fact , their distribution coincides with the availability of seagrasses . they may also be found in floating vegetation . they live in the western atlantic ocean in southern florida , bermuda , bahamas and the gulf of mexico .

dwarf seahorses are the one exception . newly hatched and enriched baby brine shrimp is generally used as a staple . this is because they are more nutritious , still having the egg yoke or being enriched . larger seahorses will not eat baby brine shrimp , its too small .

wilson mj , and acj vincent . 1998 . preliminary success in closing the life cycle of exploited seahorse species , hippocampus spp . , in captivity . aquarium sciences and conservation 2 : 179 - 196 .

, being a smaller species , is expected to live on average one year in the wild and in captivity ( if given proper care ) ( lourie et al . , 2004 ) . the maximum reported lifespan is 1 year for dwarf seahorses ( jordan and gilbert , 1882 ) .

tankmates need to be slow . seahorses are not very fast at catching food ; some will stare at a piece for a good ten minutes before deciding it is edible . highly aggressive , fast tankmates will usually end up stealing all the food . in addition , gregarious , fast moving fish tend to make seahorses nervous and can cause undue stress , which can lead to illness . keep the tankmates slow and small , and your seahorse will be happiest . or don’t keep them at all , as many seahorse keepers discovered they do best only with their own kind . for specific recommendations , see the article on seahorse tankmates .

i was in surfside this weekend and caught a very small seahorse . about an inch long . it is now in a 30 gallon ice chest filled with ocean water from where i caught him… now what… .

dwarf seahorses typically produce at least three generations per year , with four or more generations possible in the southern parts of their range [ 1 ] . most breeding activity occurs between february and october , with breeding timing and juvenile growth both closely associated with day length and regional water temperatures [ 1 , 12 ] . during the summer months , when water temperatures exceed 30°c , male dwarf seahorses may produce up to two broods per month , each containing up to 55 offspring . juvenile development is rapid , with individuals reaching reproductive maturity between two and three months of age .

plays a vital role in the ecosystems in which they live , first as predators that help regulate populations of their marine prey . as prey for other animals , dwarf seahorses help to maintain other species by providing them with a source of food . for example , consumption of small crustaceans by

the dwarf seahorse is found in eelgrass beds around coastal florida , out in the atlantic to bermuda and throughout the caribbean . in fact , their specific name zosterae refers to the genus of eelgrass with which they are most often associated : zostera . while individual specimens are reputed to be tied to one area , and they don’t move around much , their wide dispersal is apparently due to them hanging on when pieces of seagrass break loose and float off with the current to settle down sometimes hundreds of miles away .

the last issue concerning the seahorse environment is water quality . seahorses are messy eaters ; consuming large volumes of high protein , high fat foods . they have an inefficient digestive system , which leaves the aquarist with high protein , high fat poops that break down in the aquarium . for this reason , it is important for the seahorse aquarist to watch their water quality closely , and set up their aquarium to deal with these waste - producing machines .

hello i was wondering what can be done to help the bio cube not get so hot ? i have been looking into a seahorse tank and found the biocube 32 to be suitable and many people seem to use them .

i have not much idea about seahorses but i’d loved to keep them as pets . can anyone suggest me of which kind of seahorse i should get ? i prefer the one that has a long life span . thanks !

dwarf seahorses are small . specimens collected from cedar key seagrass beds by strawn ( 1958 ) ranged from 7 to 38 mm from the knob at the top of the head ( the coronet ) to the tip of the tail . robbins et al . ( 1986 ) indicates large specimens may reach 5 cm .

hello , i’m having difficulty adjusting the flow rate on the 2 different types of filters that i use in my seahorse aquarium . the current if blowing the seahorse around , no matterhow i try to slow it . in the spring i am planning to add pipefish , which also need slower water i believe . i have an undergravel plate already in place , and am thinking to give it a try , do you have any opinion on undergravel filters ?

hi dena – are you prepared for the amount of work and expense keeping seahorses requires ? what did you think of the above questions ? if you think you’re ready to keep a seahorse , i suggest starting with captive bred individuals . i would strongly recommend releasing this one back into the wild as close to where you found it as possible . and then take a look at so you want to set up a seahorse tank as a good starting point .

measuring an inch long when full grown , they are the smallest of the four seahorse species native to the gulf of mexico , and one of the smallest vertebrates on the planet . they are also thought to be slowly disappearing .

tipton and bell ( 1988 ) describe the predation strategy of dwarf sea horses as a " sit - and - wait " ambush strategy . like other syngnathids , h . zosterae is a pipette feeder ( colson et al . 1998 ) , using suctorial force to capture prey with the fused tube - like jaws .

the network visualization and genetic distance map suggest that , with the possible exception of pensacola , some gene flow occurs between sampled locations . as the distances between these locations far exceed the capacity of h . zosterae for active migration , these findings implicate passive dispersal as a common mechanism underpinning genetic connectivity in the species . passive dispersal is likely accomplished through rafting , which has been previously documented in other seahorse species [ 38 , 40 ] , and woodall et al . ’s [ 14 ] reported occurrence of a north american seahorse in european waters was likely the product of a long - range dispersal by rafting . as dwarf seahorses produce benthic offspring and have limited capacity for active dispersal , rafting provides a likely explanation for our findings of genetic intermixing between distant populations [ 1 , 13 ] .

population data for most of the worldâ€™s more than 30 seahorse species is sparse . however , worldwide coastal habitat depletion , pollution , and rampant harvesting , mainly for use in asian traditional medicine , have made several species vulnerable to extinction .

i plan to gift a seahorse to a friend . it would be nice if you could give me me detailed information about the cost involved and also any other things i should keep in mind / may overlook . thanks…loved the article !

additional observations on dwarf seahorse reproduction are provided by strawn ( 1958 ) . microscopic examination of ripe ovaries by the author revealed two clutches of eggs , one of which is comprised of large eggs ready to be transferred to the male pouch , the other of the small , yolked eggs of the successive clutch . the largest clutch size ( mature eggs only ) was 69 eggs , and the largest brood from a male was 55 young . one female usually provided all of the eggs brooded in the male marsupium , and courting males pump their pouches full of water .

our findings indicate significant population structuring among hippocampus zosterae populations in florida . we present strong evidence for the presence of a genetically distinct dwarf seahorse population ( pensacola ) , delineate two recognizable populations ( eastern keys and west coast ) , and suggest the presence of a fourth ( big pine key ) . the consistently high and strongly significant values for the various estimates of genetic differentiation employed in this study support the demarcation of the pensacola sample as markedly genetically differentiated from the rest of the seahorses collected in this study and the consideration of the population as a discrete management unit [ 37 ] . our analyses also lend credence to the suggestion made in previous studies that rafting may serve as a common means of passive dispersal facilitating genetic connectivity between geographically distant seahorse populations [ 2 , 4 , 21 , 38 ] .

range from 5 to 20 milliseconds in length and are between 2 . 65 and 3 . 43 khz . also , as size of the seahorse increases the peak frequencies of the clicking sounds decrease ( colson et al . , 1998 ) .

dwarf seahorses have a complex , four phase courtship ritual that involves color changes , performing vibrations while attached to a holdfast . they may also swim around their holdfast . then the female points her head upward , and the male responds by also pointing his head upward . then they rise up into the water column and intertwine tails .

like other seahorses , dwarf seahorses are ovoviviparous , and the female produces eggs that are reared in the male ' s brood pouch . the female produces about 55 eggs which are about 1 . 3 mm in size . it takes about 11 days for the eggs to hatch into miniature seahorses which are about 8 mm in size .

the tank size you have sounds too small . it sounds like approximately 15 gallons ( 57 ltr ) , and you’re going to want a minimum of a 29 gallon ( 110 ltr ) for most species . unless you’re thinking of keeping dwarf seahorses , which have very different requirements and then the tank would be almost too big .

after a few minutes in one spot , they would both release their grip on their seaweed perch and slowly glide to a new spot . seahorses swim upright , standing in the water with their head straight above their tails . the only means of locomotion comes from a small fin on their back . while jacque cousteau writes in his book the ocean world that this fin can move seventy times a second , it is so ineffective that the dwarf seahorse is considered to be the slowest of all fish , capable of traveling about five feet an hour . indeed , it took the pair several minutes to transit the length of the small aquarium i placed them in . despite that shortcoming , they have been around for along time . the earliest known example of a seahorse from the fossil record is 13 million years old .

dwarf seahorses are amazing animals . i see something new and different each time i look into their tank . i set up the tank right in my office next to my computer , so i can watch them all the time . of course , sometimes that distracts me when i’m writing ! the only drawback is that they need to have small , nutritious live foods all the time . if you can meet this one non - negotiable requirement , give them a try . a colony of dwarf seahorses makes an excellent display in a 2 - to 5 - gallon nano tank and might even get you interested in trying your hand at keeping and breeding other marine fish .

lourie , s . , s . foster , e . cooper , a . vincent . 2004 . " a guide to the identification of seahorses " ( on - line pdf ) . project seahorse . accessed october 14 , 2004 at urltoken .

a dwarf’s gestation period is about 10 days at 70 degrees fahrenheit . the male carries up to a dozen or so eggs in his pouch , and each day it swells a bit as the embryos grow inside him . recent studies have shown that a pseudo - placental structure develops , and the lining of the pouch changes during embryonic development .

dwarf seahorses are benthic at birth , settling onto the surrounding substrate and vegetation shortly after they emerge from their father’s pouch [ 1 , 13 ] . adult h . zosterae are poor swimmers and may experience even more limited mobility and a greater risk of predation as a result of their small size . long - range dispersal of h . zosterae is likely restricted to instances of passive dispersal through rafting , which can occur as vegetative holdfasts break loose from the substrate and are carried by ocean currents [ 4 ] . genetic exchanges between non - contiguous seahorse populations are presumed to be rare and restricted to rafting events and limited pelagic dispersal [ 2 , 11 ] . long distance dispersal through rafting has been documented in larger seahorse species , though the success of rafting as a dispersal strategy depends chiefly upon chance and favorable current patterns [ 14 ] .

medium seahorse , tends to be rather shy . may need some coaxing to eat . tends to be neutral colored , yellows but more commonly greys , cream , brown . frequently reported to avoid interaction with humans and “hide” when they are being observed .

teske pr , hamilton h , palsboll p , choo ck , gabr h , lourie sa , et al . ( 2005 ) molecular evidence for long - distance colonization in an indo - pacific seahorse lineage . mar ecol - prog ser 286 : 249–260 .

produces these sounds by the grinding of a bony articulation between the supraoccipital ridge of the neurocranium and the grooved anterior margin of the coronet . when dwarf seahorses lift their head , the ridge of the neurocranium slides under the medial groove of the coronet resulting in the clicking noise that is most likely used as a form of communication . the feeding clicks of

hoese and moore ( 1977 ) indicate individuals are restricted to high - salinity grass flats , but other authors report dwarf seahorses occupy and appear capable of breeding across a broad range of salinities . strawn ( 1958 ) , for example , reported heavy summer breeding following periods of high ( 33 ppt ) and low ( 9 . 7 ppt ) salinity .

so what is a seahorse keeper to do ? variety is the spice of life . while it may take time to convince your seahorse that mysis isn’t the only thing they want to eat , most that eat frozen will learn to eat other shrimp like frozen food , such as krill . with live food , spend the money to get live saltwater shrimp and supplement . you can also enrich food with various supplements such as vibrance or selcon . feeding live shrimp high quality foods to “gut load” for seahorses is another option .

heavy breathing / panting / coughing – seahorses tend to breath heavier than most fish , though rocking back and forth from breathing so hard , or looking though they’re coughing every few breaths is generally a sign of gill parasites or a seahorse being at death’s door .

tissue samples were collected from h . zosterae individuals from eight locations around the florida peninsula during august 2012 and january 2013 ( table 1 ) . field collections were performed through a combination of snorkeling and dip netting . fin clips were taken from the lower corner of the dorsal fin and stored in 95 % ethanol as specified by lourie [ 19 ] and lourie et al . [ 20 ] . fin clips of thirteen dwarf seahorses from indian river , florida , were provided by a collaborating researcher who obtained them from the florida department of fish and wildlife as part of a phylogenetic study of atlantic seahorse diversification [ 2 ] .

the ability of seahorses to change color in many social situations is most likely a form of communication about the state or mood of the seahorse to its mate or other members of its species ( indiviglio , 2002 ) . mates also communicate with nose pointing and body vibrations .

lourie , s . a . , a . c . j . vincent and h . j . hall , 1999 . seahorses : an identification guide to the world ' s species and their conservation . project seahorse , london . 214 p . ( ref . 30915 )

lourie , s . a . , foster , s . j . , cooper , e . w . t . and a . c . j . vincent . 2004 . a guide to the identification of seahorses . project seahorse and traffic north america . 114 pp .

caution : often sold as a tropical seahorse , but much of the water they inhabit is actually subtropical . they seem to do best for most aquarists around 68 - 70f . this species is also one that almost always needs to be kept with it’s own kind only .

hello , i read this article and your name seemed familiar . i realized that i have your seahorse book also . it has been very useful to us . i have experience with many marine fishes and other animals of all kinds but seahorses have always given me more trouble than most , so any information you could send would be appreciated . i found like you that dwarf seahorses do better than some of the larger and more expensive kinds . i am using the product you mentioned in this article , phytogreen , as brine shrimp food . my husband had selco recommended to him – would it be good to used this , or both , also ?

in nature , seahorses spend most of their time eating . this is because their digestive system is very short and not very efficient . they have evolved to be eating machines . unfortunately , they have evolved to be picky eating machines , only recognizing the movement of live food as actual food . thus comes the problem many seahorse keepers face . seahorses not only require frequent feedings of highly nutritious food , they often will only eat living food . which means for many seahorse aquarists at least one extra tank for food and a fairly large food budget .

remember , always buy captive bred ; and if possible , get directly from a breeder to limit the risks both in accurate identification and eliminating the risk from sometimes inadequate care . i strongly recommend looking at a modern guide to buying seahorses for more information on picking your seahorse .

hello randal , frank is no longer affiliated with our blog but feel free to let us know if you have any questions while setting up your new seahorse tank . h . zosterae have become much more difficult to find over the past couple of years and i would definitely recommend only getting captive - bred seahorses . most aquarium - suitable species are available through breeders at this point and are much better both for natural populations and aquarium suitability . if you are looking for more information , i would also recommend the libraries on urltoken and urltoken for seahorse information .

this is a large seahorse , very similar in shape to h . reidi . they behave much like h . reidi and are gregarious , active seahorses . common coloration : yellow with orange dots . commonly be solid yellow , yellow with black or white / light or all black .

lourie , s . a . , a . c . j . vincent and h . j . hall , 1999 . seahorses : an identification guide to the world ' s species and their conservation . project seahorse , london . 214 p . via fishbase , september 30 , 2014 .

we sometimes collect at a bay in nj and often find pipefish which i believe is the northern pipefish . your book and article mentions these as doing well with seahorses . do you think they might live with dwarf seahorses , or do they need colder water . also , we use mainly brine shrimp as live foos . . can pipefish adjust to frozen food ; is brine shrimp enough for them ?

great article . i recently saw a video of a male seahorse giving birth which brought back memories when i was a kid in the 60’s and ordered them from a magazine . i’m thinking about getting some now . what is the name of your book ? thanks for the great info . randal

i have a wild caught seahorse from the carribean , west coast of puerto rico . i will like to know the sex , age ( young or older ) if look healthy and the kind ( species ) to get a mate for her / his . can you help me , please ?

after assembling the tripod and getting set up , i focused on this tiny seahorse , no more than an inch long , and to my surprise , discovered that there were two . not only were there two , but they were holding each other ' s tails and a piece of seaweed .

seahorses are picky eaters , and the need to eat a lot . they mainly eat shrimp , but readily available brine shrimp is not an adequate diet . most captive bred seahorses eat frozen mysis and those unfortunate enough to own wild caught seahorses have to feed live foods . see our seahorse feeding guide .

tiny , newly discovered specialists the pygmy seahorse , hippocampus bargibanti , first described in 1970 , seems to live on only 2 species of gorgonians ( soft corals ) of the genus muricella . so closely does it resemble the coral’s polyps that the individual which led to the first description of the species was not discovered until it was seen on a coral that had been placed in an aquarium several days earlier ! at 0 . 8 inches in length , it was the smallest known species until the discovery , in 2003 , of indonesia’s denise’s pygmy seahorse . adults of this minute creature are a mere 0 . 6 inches long .

let’s imagine the optimum environment for a home seahorse aquarium . what would be included in the way of equipment ( what would be the standard dimension tank without the added expense of a custom built tank ? ) , live rock and and other items in the tank . which species of seahorses are considered the hardest ?


hypoplectrus nigricans , the black hamlet , is a hamlet in the family serranidae .

it is native to shallow parts of the central western atlantic ocean and caribbean sea .

it grows to about 15 cm ( 6 in ) in total length .

it is a simultaneous hermaphrodite , with a breeding strategy known as egg trading .

one fish acts as a female and lays a batch of eggs which the other fertilises .

the following night , the roles are reversed .

hypoplectrus nigricans

hypoplectrus nigricans <EOT> f st values for pair - wise comparisons of hypoplectrus nigricans allopatric populations , based on analysis of aflp data .

froese , rainer and pauly , daniel , eds . ( 2008 ) . " hypoplectrus nigricans " in fishbase . december 2008 version .

results of the f st outlier analyses between belize , honduras , and panama in hypoplectrus puella , h . nigricans , and h . unicolor

hypoplectrus nigricans is a hamlet from the western atlantic . it occasionally makes its way into the aquarium trade . it grows to a size of 15 cm in length .

aguilar - perera , a . 2004 . variations in morphology and coloration in the black hamlet , hypoplectrus nigricans ( teleostei : serranidae ) . caribbean journal of science , 40 : 150 - 154 .

numbers and types of polymorphic aflp loci resulting from pair - wise comparisons of hypoplectrus populations .

a review of the caribbean hamlets ( serranidae , hypoplectrus ) with description of two new species .

hypoplectrus nigricans isolate m63hn . b nadh dehydrogenase subunit 5 ( nd5 ) gene , partial cds ; nadh dehydrogenase subunit 6 ( nd6 ) gene , complete cds ; and trna - glu gene , partial sequence ; mitochondrial genes for mitochondrial products

hypoplectrus nigricans isolate m62hn . b nadh dehydrogenase subunit 5 ( nd5 ) gene , partial cds ; nadh dehydrogenase subunit 6 ( nd6 ) gene , complete cds ; and trna - glu gene , partial sequence ; mitochondrial genes for mitochondrial products

f st values for pair - wise comparisons of hypoplectrus chlorurus allopatric populations , based on analysis of aflp data .

f st values for pair - wise comparisons of hypoplectrus puella allopatric populations , based on analysis of aflp data .

f st values for pair - wise comparisons of hypoplectrus unicolor allopatric populations , based on analysis of aflp data .

victor , b . c . 2012 . hypoplectrus floridae n . sp . and hypoplectrus ecosur n . sp . , two new barred hamlets from the gulf of mexico ( pisces : serranidae ) : more than 3 % different in coi mtdna sequence from the caribbean hypoplectrus species flock . journal of the ocean science foundation , 5 : 1 - 19 .

citation : " black hamlets , hypoplectrus nigricans ~ marinebio . org . " marinebio conservation society . web . accessed monday , july 9 , 2018 . < urltoken > . last update : 1 / 14 / 2013 2 : 22 : 00 pm ~ contributor ( s ) : marinebio

the blue hamlet hypoplectrus gemma and its supposed model , the blue chromis chromis cyanea . photos : a & b - dr robertson .

this study is based on nine samples including three sympatric species ( the barred hamlet hypoplectrus puella , the black hamlet hypoplectrus nigricans , and the butter hamlet hypoplectrus unicolor ) from three locations ( belize , honduras , and panama ) , with 14 individuals per sample ( total 126 individuals ) . this sampling design provides the opportunity to explore the population genomic patterns of local adaptation ( between allopatric populations within species ) and speciation ( between sympatric species ) within a single system , and to repeat comparisons both taxonomically ( in three species for local adaptation ) and geographically ( in three populations for speciation ) .

domeier , m . l . 1994 . speciation in the serranid fish hypoplectrus . bulletin of marine science , 54 : 103 - 141 .

f st estimates among belize , honduras , and panama in hypoplectrus puella , h . nigricans , and h . unicolor at 10 microsatellite loci , 97 , 962 snps , and at the three repeated outliers identified in this study . n sample size , n / a data not available , – coverage below filtering criteria for these snps in these populations

fischer , e . 1980 . speciation in the hamlets ( hypoplectrus : serranidae ) : a continuing enigma . copeia , 1980 : 649 - 659 .

the yellowbelly hamlet hypoplectrus aberrans and its supposed model , the cocoa damselfish stegastes variabilis . photos : a - f charpin ; b - dr robertson .

the yellowtail hamlet hypoplectrus chlorurus and its supposed model , the yellowtail damselfish microspathodon chrysurus . photos : a - c shipley ; b - dr robertson .

the tan hamlet hypoplectrus randallorum and its supposed model , the threespot damselfish stegastes planifrons . photos : a - p lobel ; b - dr robertson .

( of plectropoma nigricans poey , 1852 ) froese , r . & d . pauly ( editors ) . ( 2018 ) . fishbase . world wide web electronic publication . , available online at urltoken [ details ]

the shy hamlet hypoplectrus guttavarius and its supposed model , the rock beauty angelfish holacanthus tricolor . photos : a - f charpin ; b – j lyle .

f st values for pair - wise comparisons of hypoplectrus sympatric morphotype populations and for pair - wise same morphotype comparisons allopatric populations , based on analysis of aflp data .

lobel , p . s . 2011 . a review of the caribbean hamlets ( serranidae , hypoplectrus ) with description of two new species . zootaxa , 3096 : 1 - 17 .

distinct geographic variation in the coloration is present in h . unicolor , h . nigricans , and h . indigo , but not in the “model” of each . h . puella and h . nigricans display geographic variation in coloration that suggests that , if their coloration is cryptic , they are more cryptic at some locations than others . thus the limited information on geographic variation in hamlet coloration indicates it occurs in both “mimic” and non - mimic hamlets and is not related to mimicry , nor , perhaps , to crypsis .

domeier , m . l . , 1994 . speciation in the serranid fish hypoplectrus . bull . mar . sci . 54 ( 1 ) : 103 - 141 . ( ref . 26407 )

graves j . e . & rosenblatt r . h . 1980 . genetic relationships of the color morphs of the serranid fish hypoplectrus unicolor . evolution , 34 ( 2 ) , 240 - 245 .

fischer [ 45 ] made intensive observations on h . nigricans and noted no behavioral interactions between it and the damselfishes or other species indicative of mimicry . he suggested that the coloration resemblance between h . nigricans and the two stegastes species is coincidental , and the result of independent selection for background - matching crypsis in each taxon . aguilar - perera [ 48 ] described geographic variation in color , shape and size of h . nigricans , with fish in the northwest caribbean being uniformly black , with short , blunt fins , while those in puerto rico are grey with yellow eyes , and have longer , more pointed fins ( see also [ 33 ] , [ 40 ] ) . if the black pattern is cryptic [ 45 ] , then the geographic variation described by aguilar - perera [ 48 ] indicates that the species may be less cryptic at some locations than others .

research hypoplectrus nigricans » barcode of life ~ bioone ~ biodiversity heritage library ~ cites ~ cornell macaulay library [ audio / video ] ~ encyclopedia of life ( eol ) ~ esa online journals ~ fishbase ~ florida museum of natural history ichthyology department ~ gbif ~ google scholar ~ itis ~ iucn redlist ( threatened status ) ~ marine species identification portal ~ ncbi ( pubmed , genbank , etc . ) ~ ocean biogeographic information system ~ plos ~ siris ~ tree of life web project ~ unep - wcmc species database ~ worms

puebla o , bermingham e , guichard f ( 2008 ) population genetic analyses of hypoplectrus coral reef fishes provide evidence that local processes are operating during the early stages of marine adaptive radiations . molecular ecology 17 : 1405–1415 .

garcía - machado e . , chevalier - monteagudo , p . p . & solignac , m . 2004 . lack of mtdna differentiation among hamlets ( hypoplectrus , serranidae ) . marine biology , 144 : 147 - 152 .

only comparisons with suitable sample sizes are shown . see table s7 for loci and outlier numbers for all comparisons . abbreviations represent the morphotypes included in each comparison : c = h . chlorurus , n = h . nigricans , p = h . puella , u = h . unicolor , v = veracruz white .

observations of behavioral interactions relating to mimicry have been made on only two of the seven hamlets originally described as mimics by randall and randall [ 3 ] and thresher [ 42 ] , h . nigricans and h . unicolor . in a detailed study of the behavioral ecology of h . nigricans , fischer [ 45 ] found no support for mimicry by this species , and suggested there was a coincidental similarity related to background matching coloration . h . unicolor and h . indigo are the only hamlets actually known to behave in a manner consistent with a mimetic relationship . how do information on hamlets in general relate to the nine predictions of the mimicry hypothesis ?

citation : holt bg , côté im , emerson bc ( 2011 ) searching for speciation genes : molecular evidence for selection associated with colour morphotypes in the caribbean reef fish genus hypoplectrus . plos one 6 ( 6 ) : e20394 . urltoken

abstract nine of the sixteen species of the western atlantic genus hypoplectrus ( serranidae ) are currently recognized to be distributed in the gulf of mexico . hypoplectrus atlahua n . sp . is only known from tuxpan banks and isla lobos , veracruz . it differs from the only other similarly colored species , h . nigricans ( i . e black hamlet ) in the number of gill rakers on the first arch , snout length , upper jaw length , pectoral and pelvic fins lengths , and coloration . it is a dark brown species , lacking nose spots , mask , caudal fin dark spots , peduncle saddle , and pectoral pigmentation , but has iridescent violet speckles and lines on cheeks and chest , and also a well - defined but rather small violet dot over the dorsal flat spine on the rear edge of the opercle .

representative images of the hypoplectrus colour morphotypes at different locations included in aflp outlier detection analysis . n . b . images for samples obtained in u . s . virgin islands not available as all individuals were released immediately after capture within this location .

aguilar - perera , a . & gonzález - salas , c . 2010 . distribution of the genus hypoplectrus v ( teleostei : serranidae ) in the greater caribbean region : support for a color - based speciation . marine ecology , 31 : 375 - 387 .

aguilar - perera , a . & tuz - sulub , a . n . 2010 . hypoplectrus gemma ( teleostei : serranidae ) is not endemic to southern florida waters . pan - american journal of aquatic sciences , 5 ( 1 ) : 143 - 146 .

holt , b . g . , côté , i . m . & emerson , b . c . 2010 . signatures of speciation ? distribution and diversity of hypoplectrus ( teleostei : serranidae ) colour morphotypes . global ecology and biogeography , 19 : 432 - 441 .

puebla , o . , bermingham , e . , guichard , f . & whiteman , e . 2007 . colour pattern as a single trait driving speciation in hypoplectrus coral reef fishes ? proceedings . biological sciences / the royal society , 274 : 1265 - 1271 .

ramon , m . l . , lobel , p . s . & sorenson , m . d . 2003 . lack of mitochondrial genetic structure in hamlets ( hypoplectrus spp . ) : recent speciation or ongoing hybridization ? . molecular ecology 12 : 2975 - 2980 .

the significant repeated outliers were detected above consistently low , but significant , genetic divergence between pairs of morphotypes ( table 2 ) . our f st values , derived from the most comprehensive taxonomic and geographic sampling to date , are in agreement with previous analyses using aflps [ 15 ] and microsatellites [ 11 ] , [ 12 ] . these results suggest that hypoplectrus morphotypes do represent more than simple colour variants of a single species and that selection acting on a limited number of loci is indirectly resulting in low level significant isolation in other parts of the hypoplectrus genome .

holt , b . g . , côté , i . m . & emerson , b . c . 2011 . searching for speciation genes : molecular evidence for selection associated with colour morphotypes in the caribbean reef fish genus hypoplectrus . plos one , 6 ( 6 ) : e20394 .

del moral flores , l . , tello - musi , j . & martíinezpérez , j . 2011 . descripción de una nueva especie del género hypoplectrus ( actinopterigi : serranidae ) del sistema arrecifal veracruzano , suroeste del golfo de méxico . revista de zoología , 22 : 1 - 10 .

our results show evidence for consistent selection between at least two hypoplectrus morphotypes ( h . chlorurus and h . puella ) and highlight three aflp loci that show good evidence for being directly affected . selection between colour forms appears to play a role in maintaining this complex of morphotypes ; however , this has not resulted in consistent divergence for the vast majority of the loci studied . the low but significant genetic differentiation between morphotypes suggests that hypoplectrus colour forms do represent more than just colour variants of a single species . however , incipient speciation cannot be assumed and these results are consistent with the possibility of an evolutionarily stable colour polymorphism .

the repeated outlier loci identified are likely to be linked , either physically or otherwise , to genes coding for hypoplectrus colour pattern . an aflp outlier analysis , similar to ours , on intertidal snails [ 25 ] was followed up by sequencing of both outlier and non - outlier loci using bacterial artificial chromosome libraries [ 26 ] , allowing speculation regarding the phenotypic effects of outlier loci . applying these techniques to the repeated outliers uncovered in this study could result in a fundamental step forward in understanding exactly how hypoplectrus morphotypes differ from each other , potentially identifying regions of the genome under selection . comparative analysis of divergent and non - divergent loci may consequently prove to be informative regarding the history of polymorphism in this genus .

hypoplectrus chlorurus , h . nigricans , h . puella and h . unicolor each provided suitable sample sizes for repeated outlier analysis . a total of 10 loci were identified using the dfdist method as being potentially under selection between morphotypes at either the 99 % or the 95 % level ( fig . 3 , table 4 ) . the frequency of repeated outliers showed the opposite pattern to that shown by general outlier frequencies , with sympatric morphotype population comparisons producing more repeated outlier loci than allopatric same morphotype comparisons . the numbers of 95sel and 99sel loci were significantly higher than expected under neutral conditions ( both p < 0 . 001 ) . the numbers of 95geo and 99geo loci did not significantly differ from null expectations , however , the relatively small sample sizes for h . puella in these analyses is likely to have reduced the probability of detecting loci in disequilibrium in these comparisons involving this species .

in this study we use established outlier detection methods to search for molecular signatures of selection on specific loci between interbreeding populations . through analysis of amplified fragment length polymorphisms ( aflps ) we specifically considered whether individual loci are consistently associated with individual morphotypes across different locations . the aflp technique has a specific advantage over mtdna and microsatellite markers that have been so far employed for population genetic analysis of hypoplectrus [ 11 ] , [ 12 ] ; by efficiently producing hundreds of markers , it has higher potential to detect polymorphism across the genome . our study took advantage of this feature to search for direct molecular evidence of selection between hypoplectrus morphotypes across different locations . this approach has an advantage over methods such as bulk segregate analysis or qtl mapping in that it can be applied to samples from natural populations and does not require laboratory breeding , which has so far proven to be unfeasible for these fish [ 7 ] .

using a genome - wide scanning approach , we found evidence for consistent selection occurring between pairs of h . chlorurus and h . puella , and between h . puella and h . unicolor pairs , despite observing low to moderate overall divergence among colour forms . three aflp loci were identified as being under selection between morphotypes in pair - wise comparisons of sympatric morphotypes at two different locations , using both the dfdist and bayescan methods . these loci represent the first evidence for selection between morphotypes influencing the hypoplectrus genome across sampling locations .

substantial inter - morphotype gene flow may at first seem to contradict the results of extensive spawning observations , in which only ∼1 % of matings occurred between different morphotypes [ 7 ] , [ 13 ] . however , even this level of interbreeding could be consistent with our observed f st values given the likely size of the majority of hypoplectrus morphotype global populations . the possibility of infrequent hybridization preventing speciation has been suggested for other systems [ 28 ] , [ 29 ] , [ 30 ] , whereby equilibrium between convergence and divergence is maintained by occasional gene flow .

hypoplectrus is a genus of small , predatory groupers endemic to the tropical northwest atlantic . it has 16 named ‘species’ [ 3 ] , [ 39 ] - [ 42 ] , eight of which have been proposed as aggressive mimics of different reef fishes [ 3 ] , [ 42 ] , [ 43 ] . below i present information on the only four species for which there are behavioral observations relating to the mimicry hypothesis . relevant information on the coloration and behavior of five other species of “mimic” hamlets and their “models” is summarized in appendix s1 , together with general information on the coloration of hamlets .

two “mimetic” hamlets , h . nigricans and h . indigo , feed heavily on fish : ∼30–40 % and 90 % of their identifiable stomach contents respectively [ 37 ] , [ 43 ] , [ 45 ] . in addition , fishes also make up about 10–25 % of the identifiable stomach contents of h . chlorurus , h . puella and h . unicolor [ 37 ] , [ 43 ] . the resemblance of the “mimetic” hamlet that specializes in preying on fish , h indigo , to its potential model , the fish it eats , is sufficiently vague that it was not among the original group of hamlets labeled as mimics due to their similarity to other fishes . caribbean reef fishes , including potential targets of some “mimic” hamlets , can readily distinguish those hamlets from their models [ 42 ] , and recognize the different ecological and threat status of each .

the relatively high level of genetic isolation demonstrated for the two sympatric morphotypes sampled in mexico is surprising , as there was no a priori reason to suspect this comparison to differ from the others . this comparison produced an f st of 0 . 212 , far larger than the level of isolation measured in all of other pair - wise comparisons ( all other f st < 0 . 09 ) . other unusual features of this region include the fact that just two morphotypes are abundant ( bgh , personal observations ) and one is an endemic morphotype , the veracruz white . the only other study to consider hamlets from the gulf of mexico [ 10 ] found that veracruz whites tend to feed at a higher trophic level than the sympatric h . nigricans population . this species pair may be an interesting focus for future research to determine what has driven the divergence between the two morphotypes in veracruz .

the overall mean f st values among morphotypes across the region and among sampling locations were similar : 0 . 051 and 0 . 052 , respectively ( for pair - wise comparisons , see table 2 ) . these values will be influenced by regional variation in the numbers of morphotypes sampled . the mean f st between sympatric morphotypes was 0 . 058 , with all pair - wise comparisons being significantly greater than zero , with the exception of the comparison of two morphotypes from honduras . within morphotypes , geographical population structure had a mean f st value of 0 . 060 ; however , there was large variation between morphotypes , ranging from 0 . 020 among h . chlorurus populations to 0 . 114 among h . nigricans populations . f st values for all sympatric inter - morphtype comparisons and all allopatric intra - morphotype comparisons are presented in tables s2 , s3 , s4 , s5 and s6 .

according to thresher [ 42 ] h . nigricans and s . adustus show parallel geographic variation in coloration , with the jamaican population of both having yellow bellies , and pelvic , anal and tail fins . however , at montego bay , jamaica , ∼50 km from thresher’s study site , s . adustus have the same uniform grey - brown color they have elsewhere in the caribbean area ( drr pers obs , at montego bay , florida , bermuda , the bahamas , panama , curacao , venezuela , barbados , and puerto rico ) . further , the jamaican coloration described for the hamlet and damselfish by thresher [ 42 ] fits other hamlets ( h . aberrans or h . chlorurus ) and stegastes variabilis . when color differences are the defining characteristic of most hamlet “species” ( see appendix s1 ) , whether to call hamlets with different color patterns intraspecific geographic variants rather than different species becomes a semantic issue .

samples were collected using scuba , from coral reef sites at eight sampling locations ( i . e . countries ) distributed across the caribbean basin ( fig . 1 ) . we refer to all individuals of a particular colour form at a particular location as a ‘morphotype population’ and all individuals of a particular colour form from throughout the hypoplectrus distribution as a ‘global morphotype population’ . fish were sampled by using micro - spears or “hook and line” whereby baited , barbless hooks were offered to fish . hooked fish were released after fin clipping . fin clips were removed from the dorsal and anal fins and placed in ethanol and stored at 4°c . the morphotypes sampled and number of individuals collected varied among locations , depending on local abundance ( table 1 ) .

the webpage text is licensed under a creative commons attribution - noncommercial 4 . 0 license

froese , r . & d . pauly ( editors ) . ( 2018 ) . fishbase . world wide web electronic publication . , available online at urltoken [ details ]

mceachran , j . d . ( 2009 ) . fishes ( vertebrata : pisces ) of the gulf of mexico , pp . 1223–1316 in : felder , d . l . and d . k . camp ( eds . ) , gulf of mexico–origins , waters , and biota . biodiversity . texas a & m ; press , college station , texas . [ details ]

html public " - / / w3c / / dtd xhtml 1 . 0 strict / / en " " urltoken "

thank you for taking the time to provide feedback on the iucn red list of threatened species website , we are grateful for your input .

there is an ongoing discussion on the validity of the hamlets as biological species ( domeier 1994 ) . hamlet " species " are defined primarily on differences in color patterns . they are known to interbreed and hybridize freely with very little consistent genetic differentiation amongst them .

anderson , w . , carpenter , k . e . , gilmore , g . , milagrosa bustamante , g . & robertson , r .

this widely distributed species is common and abundant where it occurs over shallow reefs .

there are no known major threats . therefore , it is listed as least concern .

is distributed in the western atlantic from southeast florida , the bahamas , in the gulf of mexico from the florida keys and from tuxpan , mexico along the northern yucatan to northwestern cuba , in the caribbean throughout the antilles to tobago , and along central and south america from mexico to santa marta , colombia and in the offshore islands off venezuela ( r . robertson pers . comm . 2014 ) . the depth range is three to 67 m ( lieske and myers 1994 ) , but is most abundant in less than 10 m depth .

anguilla ; antigua and barbuda ; aruba ; bahamas ; barbados ; belize ; bonaire , sint eustatius and saba ; cayman islands ; colombia ; costa rica ; cuba ; curaçao ; dominica ; dominican republic ; grenada ; guadeloupe ; guatemala ; haiti ; honduras ; jamaica ; martinique ; mexico ; montserrat ; nicaragua ; panama ; puerto rico ; saint barthélemy ; saint kitts and nevis ; saint lucia ; saint martin ( french part ) ; saint vincent and the grenadines ; sint maarten ( dutch part ) ; trinidad and tobago ; turks and caicos islands ; united states ; venezuela , bolivarian republic of ; virgin islands , british ; virgin islands , u . s .

this species is common throughout its range . in a study conducted off san blas , panama , it was the most abundant hamlet on shallow reef flats ( fischer 1980 ) .

this species inhabits shallow reefs over hard or soft corals ( lieske and myers 1994 , smith 1997 ) . members of this genus are known to be synchronous hermaphrodites with individuals alternating male and female " roles " during spawning ( fischer 1981 ) . its maximum length 15 . 2 cm tl ( randall 1996 ) .

this species rarely occurs in the aquarium trade and is not preferred ( r . robertson pers . comm . 2012 ) .

there are no known major threats . it is potentially a prey item of the invasive lionfish , however , only juveniles are consumed and it is not likely that this will drive significant population declines on a global level ( l . rocha pers . comm . 2014 ) .

anderson , w . , carpenter , k . e . , gilmore , g . , milagrosa bustamante , g . & robertson , r . 2015 .

to make use of this information , please check the < terms of use > .

greek , hypo = under + greek , plektron = sting , spur ( ref . 45335 )

marine ; reef - associated ; depth range 3 - 13 m ( ref . 9710 ) . tropical

western atlantic : belize to panama ; throughout the rest of the caribbean . absent off the coast of venezuela . antilles ( ref . 26938 ) .

maturity : l m ? range ? - ? cm max length : 15 . 2 cm tl male / unsexed ; ( ref . 13442 )

body blackish ( the intensity of the black can vary from bluish to brownish ) . all fins pigmented , including the pectorals .

a solitary species ( ref . 26340 ) inhabiting shallow reefs ( ref . 9710 ) . feeds on fishes and crustaceans ( ref . 26180 ) . often found near the bottom around soft and hard corals . occasionally been seen spawning with the h . chlorurus ( ref . 26938 )

phylogenetic diversity index ( ref . 82805 ) : pd 50 = 0 . 5000 [ uniqueness , from 0 . 5 = low to 2 . 0 = high ] .

bayesian length - weight : a = 0 . 01778 ( 0 . 00692 - 0 . 04567 ) , b = 3 . 03 ( 2 . 81 - 3 . 25 ) , in cm total length , based on lwr estimates for this ( sub ) family - body shape ( ref . 93245 ) .

trophic level ( ref . 69278 ) : 4 . 0 ±0 . 66 se ; based on food items .

resilience ( ref . 69278 ) : high , minimum population doubling time less than 15 months ( preliminary k or fecundity . ) .

vulnerability ( ref . 59153 ) : low vulnerability ( 22 of 100 ) .

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 .

html public " - / / w3c / / dtd html 4 . 01 transitional / / en " " urltoken "

claro , rodolfo , and lynne r . parenti / claro , rodolfo , kenyon c . lindeman , and l . r . parenti , eds .

nelson , joseph s . , edwin j . crossman , h . espinosa - pérez , l . t . findley , c . r . gilbert , et al . , eds .

full author list : nelson , joseph s . , edwin j . crossman , héctor espinosa - pérez , lloyd t . findley , carter r . gilbert , robert n . lea , and james d . williams

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 .

this is a clip of a video that i took following black hamlets around during the time of the day that they mate .

eol content is automatically assembled from many different content providers . as a result , from time to time you may find pages on eol that are confusing .

to request an improvement , please leave a comment on the page . thank you !

occurrence describes how often the species is found on surveys within its distribution . it is calculated as the % of reef sites surveyed by rls divers across all the ecoregions in which the species has been observed

abundance is calculated as the average number of individuals recorded per rls transect , where present .

please use this form only for a single type of error . if you see multiple errors on the page for this species , please report these in separate forms by clicking on this button again after submitting this form

thank you for highlighting this error . we appreciate your assistance in maintaining high quality control standards

head and body deep , stro ngly compressed ; forehead straight ; snout relatively short ; top jaw protrusible ; rear of top jaw exposed when mouth closed , without accessory bone above it ; teeth fixed ; preoperculum angular , serrated , several small forward pointing spines on lower edge near the corner ; gill rakers 17 - 23 ; dorsal fin x , 14 - 17 , no notch after spines , membranes between spines not indented ; pelvics long , reach to or beyond anus ; tail fin slightly forked ; lateral line scales 48 - 53 ; soft dorsal and anal fins mostly scaleless .

head and body black , grey or dark brown ; all fins except the pectorals are colored as the body ; pectorals are black in black bodied fish , clear in those with grey bodies ; there may be a bluish cast on various parts of the body and fins .

html public " - / / w3c / / dtd xhtml 1 . 0 transitional / / en " " urltoken "

warning : the ncbi web site requires javascript to function . more . . .

format summary genbank genbank ( full ) fasta asn . 1 xml insdseq xml tinyseq xml feature table accession list gi list gff3

finds sub - sequence or patterns in the sequence and highlights the matching region . the tool works with standard single letter nucleotide or protein codes including ambiguities and can match prosite patterns in protein sequences . more . . .

: missing argument 2 for checkecotox ( ) , called in / var / www / html / summary / speciessummary . php on line 1995 and defined in

: missing argument 3 for checkecotox ( ) , called in / var / www / html / summary / speciessummary . php on line 1995 and defined in

western atlantic : belize to panama ; throughout the rest of the caribbean . absent off the coast of venezuela . antilles ( ref . 26938 ) .

15 . 2 cm tl ( male / unsexed ; ( ref . 13442 ) )

depth range based on 4 specimens in 1 taxon . environmental ranges depth range ( m ) : 5 - 10 graphical representation depth range ( m ) : 5 - 10 note : this information has not been validated . check this * note * . your feedback is most welcome .

reef - associated ; marine ; depth range 3 - 13 m ( ref . 9710 )

depth : 3 - 13m . from 3 to 13 meters . habitat : reef - associated .

inhabits shallow reefs ( ref . 9710 ) . often found near the bottom around soft and hard corals . feeds on fishes and crustaceans . carnivore ( ref . 57616 ) .

the following is a representative barcode sequence , the centroid of all available sequences for this species . there are 4 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 .

eri publication repository is powered by eprints 3 which is developed by the school of electronics and computer science at the university of southampton . more information and software credits .

copyright © 1999 - 2018 john wiley & sons , inc . all rights reserved

enter your email address below . if your address has been previously registered , you will receive an email with instructions on how to reset your password . if you don ' t receive an email , you should register as a new user

html public " - / / w3c / / dtd html 4 . 01 transitional / / en " " urltoken "

marine ; occupy small territories at the foot of , or near hard or soft coral reefs .

body and fins are a mat dark blue brown to black . pelvic fins are long . length 3 - 4 . 5in . , max . 6in .

claro , r . , 1994 características generales de la ictiofauna . p . 55 - 70 . in r . claro ( ed . ) ecología de los peces marinos de cuba . instituto de oceanología academia de ciencias de cuba and centro de investigaciones de quintana roo . humann , p . and deloach , n . ( 2002 ) reef fish identification . florida , caribbean , bahamas . new world publications , inc . jacksonville , florida , usa . lieske , e . and r . myers , 1994 collins pocket guide . coral reef fishes . indo - pacific & caribbean including the red sea . haper collins publishers , 400 p . ogden , j . c . , j . a . yntema , and i . clavijo , 1975 an annotated list of the fishes of st . croix , u . s . virgin islands . spec . publ . no . 3 . smith , c . l . , 1997 national audubon society field guide to tropical marine fishes of the caribbean , the gulf of mexico , florida , the bahamas , and bermuda . alfred a . knopf , inc . , new york . 720 p .

discover a faster , simpler path to publishing in a high - quality journal . plos one promises fair , rigorous peer review , broad scope , and wide readership – a perfect fit for your research every time .

copyright : © 2011 holt et al . this is an open - access article distributed under the terms of the creative commons attribution license , which permits unrestricted use , distribution , and reproduction in any medium , provided the original author and source are credited .

funding : this work was funded by the national environment research council ( studentship s ner / sj2004 / 13064 and lsmsf application no . ek76 - 02 / 05 ) , with the additional funding by smgf and the sydney l . wright fellowship ( contribution number 1700 ) . the funders had no role in study design , data collection and analysis , decision to publish , or preparation of the manuscript .

whether speciation can occur in the absence of geographic barriers remains controversial [ 1 ] . in this context colour polymorphisms , which occur in a wide range of taxa , provide excellent opportunities for studies of intraspecific evolutionary divergence ( e . g . [ 2 ] ) . many different mechanisms have been implicated in the origin and maintenance of colour polymorphism , including sexual selection , mimicry , predation , crypsis and genetic drift [ 3 ] . as all these mechanisms may also contribute to reproductive isolation , colour polymorphisms are often considered as systems potentially undergoing speciation ( e . g . [ 4 ] ) .

1 = bermuda , 2 = curaçao , 3 = dominican republic , 4 = honduras , 5 = mexico , 6 = panama , 7 = puerto rico , 8 = u . s . virgin islands .

the aflp procedure was based on vos et al . , [ 16 ] . dna was isolated from ≈0 . 5 cm 2 sub - samples of fin clips , using a phenol - chloroform extraction method [ 17 ] . extractions were checked for concentration and purity to ensure isolated dna was suitable for the production of clear repeatable aflp profiles . for each sample , 100 ng of dna ( 10 µl solution ) was added to 1 . 4 µl restriction digestion mixture containing 1 u ecori and 1 u msei restriction enzymes , along with 1 . 1 µl 10×ta reaction buffer ( 100 mm tris - ac ph 7 . 9 , 100 mm mgac , 500 mm kac , 10 mm dithiothreitol ( dtt ) ) and 3 µg bsa . dna was digested for three hours at 37°c . digested dna was added to 5 . 5 µl of ligation mastermix containing 1 µl 5× t4 ligase buffer , 0 . 5 u t4 ligase , 25 pmol of ecori adaptor and 25 pmol of mse adaptor ( table s1 ) . this solution was incubated overnight at 16°c and gel electrophoresis used to ensure that the dna was fully digested . 2 µl of diluted digestion mixture was used for the pre - selective pcr , which was run in 10 µl total solution containing 5 pmol of primer eco p and 5 pmol of mse p ( table s1 ) , along with 1 µl 10× pcr buffer , 15 nmol mgcl 2 , 2 nmol dntp and 0 . 25 u taq dna polymerase . the pre - selective pcr amplification comprised an initial denaturation step of two minutes at 94°c , followed by 20 cycles of denaturation at 94°c for 20 seconds , annealing at 56°c for 30 seconds and final extension at 72°c for two minutes .

pre - selective amplifications were checked using gel electrophoresis and then diluted to 1∶20 concentration by the addition of sterile distilled water . 1 µl of pre - selective pcr amplification was used as the template for the selective pcr , which was added to 9 µl pcr mixture containing 5 pmol of each selective primer ( table s1 ) , 1 µl 10× pcr buffer , 20 nmol mgcl 2 , 2 nmol dntp and 0 . 25 u taq dna polymerase . eco p selective primers were labelled with either fam or ned fluorescent labels for genotyping . pcr products were diluted 10× with sterile distilled water , and 5 µl of diluted product of fam - labelled samples were mixed with an equal quantity of ned - labelled samples for multiplex genotyping . 0 . 5 µl of the combined diluted product was then added to 9 . 45 µl hidi formamide and 0 . 05 µl abi rox size standard . prior to genotyping all samples were denatured at 95°c for three minutes and then quenched on ice for a further three minutes . control samples were added to every 96 - well pcr reaction plate to ensure repeatability between runs .

samples were genotyped using an abi 3730 capillary dna analyser . the fluorescent spectra of ned and fam labels do not overlap ; however , the possibility that the two combined samples interfered with each other ' s aflp profiles was investigated by genotyping several individuals , both singly and also after combining with an alternatively labelled sample . combined dye samples proved to be equally as reliable as single dye samples . primer combinations were chosen after screening 32 different primer combinations for profile quality ( i . e . whether the presence or absence of individual peaks could be clearly determined ) and polymorphism ( i . e . there appeared to be high variation in peak presence / absence between individual profiles ) . primer pairs showing the highest levels of polymorphism were selected for further analysis .

the frequencies of 95 % and 99 % outliers detected using dfdist were checked for the assumptions of parametric analysis and then compared with relevant neutral expectations . neutral expectations were assumed to be 5 % and 1 % of the total number of polymorphic loci for each comparison , for the 95 % and 99 % levels respectively . the pair - wise comparisons included in this analysis were all nine sympatric morphotype comparisons ( excluding morphotype populations with sample sizes of six or fewer individuals ) as well as nine randomly selected allopatric same - morphotype comparisons and nine randomly selected allopatric different - morphotype comparisons . the mean % of outlier loci for each type of morphotype population comparison was compared against neutral expectations .

the second analytical method we applied to our data was a fully bayesian approach developed by foll & gaggiotti [ 23 ] , which uses the software bayescan ( available at urltoken ) . this method extends the approach developed by beaumont & balding [ 24 ] , in order to allow the use of dominant markers ( such as aflps ) and to rigorously estimate the probability that each specific locus is subject to selection , rather than solely returning the probability of a locus being selectively neutral . to provide an independent test of the repeated outliers detected using dfdist , the same pair - wise comparisons were analysed using bayescan and loci showing probability values higher than 0 . 7 for the likelihood of being under directional selection were noted ( as per [ 23 ] ) . repeated dfdist outliers that the bayescan did not find to be under selection in either comparison are considered to be false positives , those which are found to be under selection in only one comparison may be false positives or , alternatively , may represent local selection that is not consistent across morphotype populations . outliers that are shown in both pair - wise comparisons using both methods are likely to be under selection between morphotypes .

a total of 528 hamlets were sampled from eight different locations representing five different colour morphotypes , with considerable variation among the numbers of each morphotype found at each location ( table 1 ) . representative images of the morphotypes sampled at each location are presented in figure s1 . a total of 436 scorable aflp loci were produced with an overall repeatability rate of 97 . 1 % ( see table s1 for primer combinations ) . of these , 423 loci were polymorphic , i . e . , they were scored differently in at least one individual .

global morphotypes ( i . e . all individuals of a given morph collected across all locations ) .

morphotype populations ( i . e . individuals of a given morph at a given sampling location ) .

left hand plots represent pairwise comparisons for populations of h . chlorurus and h . puella in curacao and panama . right hand plots represent pairwise comparisons for populations of h . puella and h . unicolor in curacao and panama . “sym” refers to sympatric comparisons of the two morphotypes concerned ( followed by the location ) , “allo” refers to allopatric comparisons of the two locations concerned ( followed by the morphotype ) . letters refer to loci repeated across sympatric comparisons ( see table 4 for full loci names and further details ) . dashed lines represent the simulated 95 % f st level , dotted lines represent the simulated 99 % f st level . repeated outlier comparisons that did not return any outliers repeated across sympatric comparisons are not shown .

values that were significantly higher than expected in the absence of selection between colour morphotypes , in pair - wise comparisons at two separate locations , using both dfdist and bayescan outlier detection methods .

the bayescan analysis showed mixed support for the repeated outliers identified using dfdist . three of the outliers repeated across different comparisons of h . chlorurus and h . puella were also identified as being repeatedly under selection using bayescan . the remaining seven dfdist outliers were either only identified in one comparison ( four outliers ) or not identified in any comparison ( three outliers ) as being under selection between morphotypes by this analysis ( table 4 ) .

for the majority of loci , differentiation between sympatric morphotypes appears to be no more consistent than differentiation shown between allopatric populations of the same morphotype ( table 3 ) . overall , pair - wise comparisons of sympatric morphotype populations produced more outliers than expected under neutral conditions but this difference was not significant . by comparison , analysis of allopatric populations composed of the same two morphotypes did reveal a significantly higher number of 99 % outliers than expected under neutral conditions , although the number of 95 % outliers did not significantly exceed null expectations .

the hamlet system has attracted considerable attention as a potential case study for speciation in the marine environment . however , the identification of loci specifically associated with certain morphotypes does not necessarily imply that divergence between morphotypes is currently ongoing . an alternative explanation for these results is that assortative mating , linked to the simultaneous hermaphroditism in these fish [ 8 ] , is maintaining divergence between morphotypes but inter - morphotype reproductive isolation is not fully complete and some successful interbreeding between morphotypes is limiting further divergence . gene flow between morphotypes would also explain the lack of association between mitochondrial sequence haplotypes and morphotypes shown in other studies [ 11 ] , [ 14 ] , [ 27 ] .

we would like to thank terry burke , andy krupa , raj whitlock and all at the sheffield molecular genetics facility ( smgf ) , who provided first rate advice and facilities for a large part of the aflp work . we would also like to thank oscar puebla and dr e bermingham for their help in the field and for agreeing to review an early draft of this manuscript . we thank dr e whiteman and the staff at magueyes laboratories ( puerto rico ) , carmabi ( curaçao ) , the national aquarium ( dominican republic ) , centre of ecology & fisheries ( mexico ) and b . b . s . r . ( bermuda ) for their support in the field . special thanks to yolanda leon , thad murdoch , horacio perez , joanna pitt , and monica vega for their invaluable assistance .

conceived and designed the experiments : bgh imc bce . performed the experiments : bgh . analyzed the data : bgh bce . wrote the paper : bgh imc bce .

alexander hj , breden f ( 2004 ) sexual isolation and extreme morphological divergence in the cumaná guppy : a possible case of incipient speciation . journal of evolutionary biology 17 : 1238–1254 .

gray sm , mckinnon js ( 2007 ) linking color polymorphism maintenance and speciation . trends in ecology & evolution 22 : 71–79 .

pierotti mer , seehausen o ( 2007 ) male mating preferences pre - date the origin of a female trait polymorphism in an incipient species complex of lake victoria cichlids . journal of evolutionary biology 20 : 240–248 .

bierne n , bonhomme f , david p ( 2003 ) habitat preference and the marine - speciation paradox . proceedings of the royal society b - biological sciences 270 : 1399–1406 .

palumbi sr ( 1992 ) marine speciation on a small planet . trends in ecology & evolution 7 : 114–118 .

( teleostei : serranidae ) colour morphotypes . global ecology and biogeography 19 : 432–441 .

species complex reveals no evidence for dietary niche divergence . marine ecology - progress series 357 : 283–289 .

mccartney ma , acevedo j , heredia c , rico c , quenoville b , et al . ( 2003 ) genetic mosaic in a marine species flock . molecular ecology 12 : 2963–2973 .

coral reef fishes ? proceedings of the royal society b - biological sciences 274 : 1265–1271 .

barreto fs , mccartney ma ( 2008 ) extraordinary aflp fingerprint similarity despite strong assortative mating between reef fish color morphospecies . evolution 62 : 226–233 .

vos p , hogers r , bleeker m , reijans m , vandelee t , et al . ( 1995 ) aflp - a new technique for dna fingerprinting . nucleic acids research 23 : 4407–4414 .

sambrook j , fritsch ef , maniatis t ( 1989 ) molecular cloning : a laboratory manual . new york : cold spring harbor press .

whitlock r , hipperson h , mannarelli m , butlin rk , burke t ( 2008 ) an objective , rapid and reproducible method for scoring aflp peak - height data that minimizes genotyping error . molecular ecology resources 8 : 725–735 .

vekemans x ( 2002 ) aflp - surv version 1 . 0 . distributed by the author . laboratoire de génétique et ecologie , végétale , université libre de bruxelles , belgium .

beaumont ma , nichols ra ( 1996 ) evaluating loci for use in the genetic analysis of population structure . proceedings of the royal society of london series b : biological sciences 263 : 1619–1626 .

zhivotovsky la ( 1999 ) estimating population structure in diploids with multilocus dominant dna markers . molecular ecology 8 : 907–913 .

nosil p , egan sp , funk dj ( 2008 ) heterogeneous genomic differentiation between walking - stick ecotypes : “isolation by adaptation” and multiple roles for divergent selection . evolution 62 : 316–336 .

foll m , gaggiotti o ( 2008 ) a genome - scan method to identify selected loci appropriate for both dominant and codominant markers : a bayesian perspective . genetics 180 : 977–993 .