Animal Diversity Web

Ge­o­graphic Range

Pea­cock floun­ders, Bothus lu­na­tus, live in the the West At­lantic Ocean in both trop­i­cal and sub­trop­i­cal re­gions. They are found off the coasts of Florida, Bermuda, and down the coast of South Amer­ica to Brazil. They have also been recorded in the Cen­tral At­lantic near the shelf of As­cen­sion and the St. Helen Is­lands as well as in the East­ern At­lantic in the Gulf of Guinea. (Evseenko, 2008; Miller, et al., 1991; Robins and Ray, 1986)

• Biogeographic Regions
• atlantic ocean
  • native

Habi­tat

Pea­cock floun­ders are ma­rine flat­fish, liv­ing in clear oceanic wa­ters. They live a ben­thic lifestyle on sand and rock bot­toms, in­clud­ing coral reef en­vi­ron­ments. They can be found at depths as great as 80 m. (Miller, et al., 1991; Robins and Ray, 1986)

• Habitat Regions
• tropical
• saltwater or marine

• Aquatic Biomes
• reef
• coastal

• Range depth

  0 to 80 m

  0.00 to 262.47 ft

Phys­i­cal De­scrip­tion

Like their near rel­a­tives, adult pea­cock floun­ders are flat­tened and cir­cu­lar in shape, with both eyes lo­cated on one side of their body. In mem­bers of the fam­ily Both­idae, in­clud­ing pea­cock floun­ders, eyes ap­pear on the left side, which is also more brightly col­ored. Mem­bers of this fam­ily pos­sess un­equal pelvic fins; the fin on the eye-side is longer. Adults av­er­age 35 mm in length and can mea­sure as much as 45 mm.

Pea­cock floun­ders are brown in color, dec­o­rated with bright blue rings and ad­di­tional blue spots near the head and fin area. There are usu­ally 2 to 3 dark smudges along the lat­eral line. Un­like other species in the genus Bothus, pea­cock floun­ders have a deep notch in front of their eyes. Like most other floun­ders, adults can rapidly change color, which is used to blend in with the sea bot­tom. (Miller, et al., 1991; Robins and Ray, 1986)

Male and fe­male pea­cock floun­der look si­m­il­iar, al­though males have thread­like up­per-pec­toral fin rays that fe­males lack. Males oc­ca­sion­ally have a longer pec­toral fin on the eye-side than fe­males. (Evseenko, 2008)

Pea­cock floun­der lar­vae look very dif­fer­ent than adults. Lar­vae are 5.5 to 39.5 mm in length, with each eye on a sep­a­rate side of the flat­tened body. Dor­sal and anal fins are fully formed in the lar­val stage, and an elon­gated ray emerges from the dor­sal fin. Lar­vae are al­most free of pig­ment, mak­ing them nearly trans­par­ent. The only pig­men­ta­tion ap­pears as a clus­ter of melanophores at the base of the elon­gated ray of the dor­sal fin. Lar­vae also have no teeth. (Evseenko, 2008)

• Other Physical Features
• ectothermic
• heterothermic
• bilateral symmetry

• Sexual Dimorphism
• sexes shaped differently

• Range length

  45 (high) cm

  17.72 (high) in

• Average length

  35 cm

  13.78 in

De­vel­op­ment

Pea­cock floun­ders have three stages of life: egg, lar­val, and adult. Lar­vae and adults dif­fer in col­oration, body shape, and sym­me­try. As lar­vae be­come adults, body depth in­creases and shape be­comes more cir­cu­lar. The swim blad­der pre­sent in lar­vae dis­ap­pears, and adults de­velop teeth. An­other con­sid­er­able change in mor­phol­ogy is the mi­gra­tion of the right eye to the left side of the body. As this mi­gra­tion oc­curs, pea­cock floun­ders be­come asym­met­ri­cal and blind on the right side. Eye mi­gra­tion oc­curs through a slit formed dur­ing sep­a­ra­tion of the dor­sal fin from the cra­nium. This method is dis­tinc­tive of this species; other closely re­lated species uti­lize a hole in their head for this process. (Evseenko, 2008)

Changes in pig­men­ta­tion also occur dur­ing meta­mor­pho­sis of pea­cock floun­ders. Sim­i­lar to those in re­lated flat­fishes, lar­val melanophores (pig­ment-cells) are pre­sent on both sides of the body, but are not abun­dant. Dur­ing meta­mor­pho­sis, melanophores dis­ap­pear from the blind side and are pre­sent only on the eye-side. The final pat­tern is de­ter­mined by dif­fer­en­ti­a­tion of adult pig­ment cells. (Bolker and Hill, 2005)

Sex dif­fer­en­ti­a­tion of pea­cock floun­ders is con­trolled by the en­docrine sys­tem. Her­maph­ro­dites are rare. Lev­els of var­i­ous sex steroid hor­mones have di­rect ef­fect on germ cell de­vel­op­ment, lead­ing to the for­ma­tion of dif­fer­ent go­nads, ei­ther male or fe­male sex or­gans and as­so­ci­ated sec­ondary sex char­ac­ter­is­tics. (De­vlin and Na­ga­hama, 2002; Kon­stan­ti­nou, 1994)

• Development - Life Cycle
• metamorphosis

Re­pro­duc­tion

Pea­cock floun­ders have a "harem" mat­ing sys­tem, in which one male mates with mul­ti­ple fe­males. Sev­eral fe­males have sub-ter­ri­to­ries within a male's ter­ri­tory. On av­er­age, one male mates with 6 fe­males. Males are de­fen­sive of their ter­ri­tory and the fe­males within their ter­ri­tory, deny­ing ac­cess to other males.

Mat­ing ac­tiv­i­ties usu­ally begin just be­fore dusk. At this time, a male and a fe­male ap­proach each other with the oc­u­lar pec­toral fin erect. The two fish arch their backs and touch snouts. After this in­ter­ac­tion the fe­male swims away, and the male some­times fol­lows, ap­proach­ing the fe­male again from the left side. At this point the male pec­toral fin is erect and the fe­male pec­toral fin moves up and down, pos­si­bly sig­nal­ing will­ing­ness to mate. The male then po­si­tions him­self un­der­neath the fe­male and mat­ing be­gins. This process con­sists of a mat­ing rise, dur­ing which the fe­male and male rise in the water col­umn to­gether. On av­er­age, these rises last about 15 sec­onds. At the high­est point of this rise, usu­ally around 2 m above the sub­strate, ga­metes from both fish are si­mul­ta­ne­ously re­leased, pro­duc­ing a cloud of sperm and eggs. Once the cou­ple re­turns from the rise, the male "checks" to make sure mat­ing was suc­cess­ful, and the pair sep­a­rates quickly, swim­ming away from each other in op­po­site di­rec­tions. Not all mat­ing rises are suc­cess­ful, and the process of "check­ing" is thus im­por­tant. The exact pur­pose of the mat­ing rise in these floun­ders un­known; pos­si­ble rea­sons for ris­ing in­clude bet­ter dis­per­sal of ga­metes and preda­tor avoid­ance. (Kon­stan­ti­nou, 1994; Miller, et al., 1991)

• Mating System
• polygynous

Pea­cock floun­ders have ex­tended spawn­ing pe­ri­ods and par­tic­i­pate in "se­r­ial spawn­ing." Fe­males pro­duce eggs in large batches, and there­fore many eggs are fer­til­ized at once. This strat­egy is used by many fam­i­lies of fish, in­clud­ing both­ids, soles, tongue­fish, and other fish that live at lower lat­i­tudes.

Spawn­ing may be trig­gered by warm­ing and cool­ing trends. In­di­vid­u­als in the mid-At­lantic travel north dur­ing spring and south dur­ing au­tumn to spawn.

Pea­cock floun­ders do not reach sex­ual ma­tu­rity di­rectly after meta­mor­pho­sis, but rather spend time as ju­ve­niles. This time varies among in­di­vid­u­als, par­tic­u­larly among in­di­vid­u­als liv­ing in dif­fer­ent areas with dif­fer­ent re­sources. (Gib­son, 1994; Kon­stan­ti­nou, 1994; Miller, et al., 1991; van der Veer, et al., 2005)

• Key Reproductive Features
• year-round breeding
• sexual
• fertilization
  • external
• broadcast (group) spawning
• oviparous

• Breeding interval

  Peacock flounders breed serially.

• Breeding season

  Peacock flounders breed year-round.

Be­cause pea­cock floun­ders prac­tice broad­cast spawn­ing, many small eggs are pro­duced at once, which sug­gests no post-zy­gotic parental in­volve­ment. The sur­vival rate for in­di­vid­ual zy­gotes or lar­vae is very low. (Thresher, 1988)

• Parental Investment
• no parental involvement
• pre-fertilization
  • protecting
    • male

Lifes­pan/Longevity

Lit­tle in­for­ma­tion is avail­able re­gard­ing the lifes­pan of pea­cock floun­ders, though it is likely si­m­il­iar to that of other floun­ders liv­ing in the same ge­o­graphic range.

Be­hav­ior

Pea­cock floun­ders are soli­tary, motile, and live a ben­thic lifestyle.

Male floun­ders have dis­tinct ter­ri­to­ries that do not over­lap. Each male de­fends its own ter­ri­tory and ex­hibits de­fen­sive be­hav­ior when other males enter their claimed area. Males chase off in­trud­ers and dis­play ag­gres­sive be­hav­ior to­ward other males. Fe­males, how­ever, do not usu­ally dis­play ag­gres­sive be­hav­ior. Fe­males do not have the same types of ter­ri­to­ries, but rather have des­ig­nated sub­units that are smaller in area. Day­time ter­ri­to­ries are not the same as night re­tire­ment sites for mem­bers of ei­ther sex. Males re­tire closer to shore and fe­males in deeper water, re­turn­ing to their day­time ter­ri­to­ries early in the morn­ing.

When pea­cock floun­ders are threat­ened, they dive into the sub­strate. They stay hid­den, partly cov­ered in sand, until the preda­tor or other dis­tur­bance is gone. (Kon­stan­ti­nou, 1994; Miller, et al., 1991; Shul­man, 1985)

Many flat­fishes, in­clud­ing pea­cock floun­ders, have the ca­pac­ity to in­duce changes in their col­oration, often in order to match their back­ground, the bot­tom of the ocean. This be­hav­ior is con­trolled through neu­ro­trans­mit­ters, which send sig­nals that me­di­ate changes in the melanophores. Dif­fer­ent col­ors re­sult from dif­fer­ent con­cen­tra­tions of pig­ment gran­ules in dif­fer­ent areas. These changes are al­ways re­versible. (Bolker and Hill, 2005)

• Key Behaviors
• natatorial
• diurnal
• motile
• territorial

• Range territory size

  20 to 360 m^2

Home Range

Al­though in­di­vid­u­als spend their days and nights in sep­a­rate areas, the over­all home range of pea­cock floun­ders is not large. Male floun­ders in­habit ter­ri­to­ries any­where from 50 to 360 sq m, and fe­males in­habit smaller areas within these ter­ri­to­ries, from 20 to 50 sq m. Al­though pea­cock floun­ders oc­ca­sion­ally mi­grate in order to spawn, this is not typ­i­cal. (Kon­stan­ti­nou, 1994)

Com­mu­ni­ca­tion and Per­cep­tion

Pea­cock floun­ders have a lat­eral line, a sense organ that de­tects move­ments and vi­bra­tions in the water. The eyes on the top of the adult body are used as vi­sual or­gans. Po­ten­tial mates com­mu­ni­cate through touch, using the oc­u­lar pec­toral fin. After the mat­ing process, males per­form a be­hav­ior called "check­ing" in order to make sure mat­ing was suc­cess­ful. Some kind of sig­nal is sent be­tween or­gan­isms at this time, but it is un­known whether this is a vi­sual sig­nal or a chem­i­cal (pheromonal) sig­nal. (Kon­stan­ti­nou, 1994)

• Communication Channels
• visual
• tactile
• chemical

• Other Communication Modes
• vibrations

• Perception Channels
• visual
• tactile
• vibrations
• chemical

Food Habits

Adult pea­cock floun­ders are re­stricted to feed­ing on other ben­thic or­gan­isms. They are ac­tive preda­tors, mostly eat­ing other fish; how­ever, pea­cock floun­ders can also feed on ma­rine in­ver­te­brates, such as crus­taceans and some­times oc­topi. (Danilow­icz and Sale, 1999; Gochfeld and Olsen, 2009; Kauf­man and Eber­sole, 1984; Kon­stan­ti­nou, 1994)

Pea­cock floun­ders have also been ob­served feed­ing on French grunts and Caribbean sharp­nose puffers. The lat­ter is some­what toxic, and it has been spec­u­lated that pea­cock floun­ders have a unique feed­ing be­hav­ior to ef­fec­tively stun prey. (Danilow­icz and Sale, 1999; Gochfeld and Olsen, 2009)

The food of lar­val and ju­ve­nile pea­cock floun­ders is not well doc­u­mented. How­ever, the diet of ju­ve­niles of other floun­der species com­monly in­cludes drift and ben­thic algae. (Shul­man, 1985)

• Primary Diet
• carnivore
  • piscivore

• Animal Foods
• fish
• mollusks
• aquatic crustaceans
• other marine invertebrates

• Plant Foods
• algae

Pre­da­tion

Preda­tors of adult and lar­val pea­cock floun­ders in­clude large fish, sharks, and rays. Adults are also preyed upon by var­i­ous species of snap­pers, in­clud­ing ma­hogany snap­pers and yel­low­tail snap­pers. (Shul­man, 1985)

Be­cause pea­cock floun­ders are at a high risk for pre­da­tion, they have ac­quired sev­eral adap­tions to avoid being eaten. One im­por­tant adap­tion is their abil­ity to change color to blend in with sur­round­ings. When they are spot­ted, how­ever, they often dive into the sub­strate, hid­ing in the sand to avoid cap­ture. Spawn­ing at dusk re­duces the chance of pre­da­tion dur­ing mat­ing, be­cause there are not as many po­ten­tial preda­tors in the water col­umn at this time. The up­ward mat­ing rise may also con­fuse preda­tors. Fi­nally, liv­ing pri­mar­ily in shal­low wa­ters low­ers the risk of pre­da­tion, as fewer larger fish live in these areas. (Gib­son, 1994; Kauf­man and Eber­sole, 1984; Miller, et al., 1991)

• Anti-predator Adaptations
• cryptic

• Known Predators

  • Mahogany snapper Kytjanus mahogoni
  • Yellowtail snapper Olyurus chrysurus
  • sharks Selachimorpha
  • rays Batoidea

Ecosys­tem Roles

Pea­cock floun­ders act as prey for larger fish and as preda­tors to smaller fish and ma­rine in­ver­te­brates. They do not have sig­nif­i­cant par­a­sites. (Kauf­man and Eber­sole, 1984; Shul­man, 1985)

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Pea­cock floun­ders are of minor im­por­tance in com­mer­cial fish­ing, and they oc­ca­sion­ally ap­pear in the aquar­ium trade. (Froeser and Bailly, 2004)

• Positive Impacts
• pet trade
• food

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

There are no known ad­verse ef­fects of pea­cock floun­ders on hu­mans.

Con­ser­va­tion Sta­tus

Pea­cock floun­ders are gen­er­ally not con­sid­ered threat­ened, but they have not been eval­u­ated by the IUCN or the US Fish and Wildlife Ser­vice.

• IUCN Red List

  Not Evaluated

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  No special status

Other Com­ments

Com­mon names for Bothus lu­na­tus in­clude "pea­cock floun­der" and "plate fish."

Con­trib­u­tors

Kelsey Ot­ter­bein (au­thor), Uni­ver­sity of Michi­gan-Ann Arbor, Phil Myers (ed­i­tor), Uni­ver­sity of Michi­gan-Ann Arbor, Gail Mc­Cormick (ed­i­tor), An­i­mal Di­ver­sity Web Staff.

Ref­er­ences

Bolker, J., C. Hill. 2005. Pig­men­ta­tion de­vel­op­ment in hatch­ery-reared flat­fishes. Jour­nal of Fish Bi­ol­ogy, 56/5: 1029 - 1052.

Danilow­icz, B., P. Sale. 1999. Rel­a­tive In­ten­sity of Pre­da­tion on the French Grunt, Haemu­lon flavo­lin­ea­tum, Dur­ing Di­ur­nal, Dusk, and Noc­tur­nal Pe­ri­ods on a Coral Reef. Ma­rine Bi­ol­ogy, 133/2: 337-343.

De­vlin, R., Y. Na­ga­hama. 2002. Sex De­ter­mi­na­tion and Sex Dif­fer­en­ti­a­tion in Fish: An Overview of Ge­netic, Phys­i­o­log­i­cal, and En­vi­ron­men­tal In­flu­ences. Aqua­cul­ture, 208/3-4: 191-364.

Evseenko, S. 2008. Early Life Stages of Pea­cock Floun­der "Bothus Lu­na­tus" (Both­idae) from the West­ern and Cen­tral Trop­i­cal At­lantic. Jour­nal of Ichthy­ol­ogy, 48/7: 515-524.

Froeser, R., N. Bailly. 2004. "Fish­base" (On-line). Ac­cessed April 21, 2010 at http://​www.​fishbase.​us/​summary/​SpeciesSummary.​php?​id=978.

Gib­son, R. 1994. Im­pact of Habi­tat Qual­ity and Quan­tity on the Re­cruit­ment of Ju­ve­nile Flat­fishes. Nether­lands Jour­nal of Sea Re­search, 32/2: 191-206.

Gochfeld, D., J. Olsen. 2009. A Novel Feed­ing Be­hav­ior by an Am­bush Preda­tor on Toxic Prey. Coral Reefs, 28/1: 155.

Kauf­man, L., J. Eber­sole. 1984. Mi­cro­ta­pog­ra­phy and the Or­ga­ni­za­tion of Two As­sem­blages of Coral Reef Fishes in the West In­dies. Jour­nal of Ex­per­i­men­tal Ma­rine Bi­ol­ogy and Ecol­ogy, 78: 253-268.

Kon­stan­ti­nou, 1994. The so­cial and re­pro­duc­tive be­hav­ior of the eyed floun­der, Bothus ocel­la­tus, with notes on the spawn­ing of Bothus lu­na­tus and Bothus el­lip­ti­cus. En­vi­ron­men­tal bi­ol­ogy of fishes, 44/4: 311-324.

Miller, J., J. Burke, G. Fitzhugh. 1991. Early Life His­tory Pat­terns of At­lantic Amer­i­can Flat­fish: Likely (and Un­likely) Fac­tors Con­trol­ling Re­cruit­ment. Nether­lands Jour­nal of Sea Re­search, 27/3: 261-275.

Nel­son, J. 2006. Fishes of the World, Fourth Edi­tion. Hobo­ken, NJ: John Wiley & Sons, Inc..

Oys­tein, S., H. Smara­dit­tir, K. Pittman. 2006. Twisted Story of Eye Mi­gra­tion in Flat­fish. Jour­nal of Morh­phol­ogy, 267/6: 730-788.

Ran­dall, J. 1967. Food Habits of Reef Fishes of the West In­dies. Stud. Trop. Oceanagr., 5: 665-847.

Robins, C., C. Ray. 1986. A Field Guide to At­lantic Coast Fish­e­sof North Amer­ica. Boston, U.S.A.: Houghton Mif­flin Com­pany.

Shul­man, M. 1985. Re­cruit­ment of Coral Reef Fishes: Ef­fects of Dis­tri­b­u­tion of Preda­tors and Shel­ter. Ecol­ogy, 66/3: 1056-1066.

Sum­ner, F. 2005. The ad­just­ment of flat­fishes to var­i­ous back­grounds: A study of adap­tive color change. Jour­nal of Ex­per­i­men­tal Zo­ol­ogy, 10/4: 409-506.

Thresher, R. 1988. Lat­i­tu­di­nal Vari­a­tion in Egg Sizes of Trop­i­cal and Sub-trop­i­cal North At­lantic Shore Fishes. En­vi­ron­men­tal Bi­ol­ogy of Fishes, 21/1: 17-25.

van der Veer, H., R. Burghahn, J. Miller, A. Ri­jins­dorp. 2005. Re­cruit­ment in Flat­fish, with Spe­cial Em­pha­sis on North At­lantic Specis: Progress Made by the Flat­fish Sym­posia. ICES Jour­nal of Ma­rine Sci­ence, 57/2: 202-215.