Many juvenile wrasses are cryptically colored to avoid predation while others find protection among the tentacles of sea anemones. Nearly all adult wrasses bury themselves in sand at night to avoid predators. A few species seek out reef crevices and produce a foul-smelling mucous bag to deter predators while sleeping. Razorfishes (Hemipteronotus, Xyrichtys) also use the sand for protection during the day by diving into the bottom. Razorfishes are apparently quite agile in this environment, sometimes resurfacing several meters from the point of entry.
Known Predators:
Anti-predator Adaptations: mimic; cryptic
A unique feature of some parrotfishes is the production of a mucous envelope at night before resting. The envelope takes about 30 minutes to construct and is open at both ends to allow water flow. The secreted envelope is foul smelling and tasting, which may serve to deter nighttime predators that hunt by scent. Most parrotfishes seek out caves and ledges in the reef for protection at night, but parrotfishes in the genus Cryptotomus bury themselves in the sand like wrasses. After creating a hole in the sand Cryptotomus then produces its mucous nightgown.
Known Predators:
Parrotfishes are characterized by their distinctive beak-like jaws, in which the teeth are fused together in most species, and a pharyngeal apparatus , which acts as a second set of jaws in the throat. In the pharyngeal apparatus, the teeth are arranged in rows and are highly specialized to grind, crop, and crush food as it is processed. Parrotfishes have large, cycloid scales , usually with 22-24 scales along the lateral line. The dorsal fin has nine spines and ten soft rays. The anal fin has three spines and nine soft rays, and the pelvic fins one spine and five soft rays. (Click here to see a fish diagram).
Some parrotfishes have a complex socio-sexual (socially influenced sexual change) system punctuated by three phases, and each phase change results in a different color pattern (See Reproduction: Mating Systems for a description of “phases” in parrotfishes). For instance, juveniles tend to have a drab mixture of browns, grays and blacks, but as they mature a distinct coloration emerges with the addition of red tones. A third set of colors is donned by males and by females that have recently undergone sex change into males. As these males mature, they exhibit bright, intricate patterns of reds, greens, and blues. This type of color change has been documented in Scarus, Sparisoma, Nicholsina, Bolbometapon, and Cryptotomus, but there are some monochromic (fishes that do not exhibit sexual color change) species that exhibit different types of sexual dimorphism.
Scarus coelestinus and Scarus coeruleus in the eastern Pacific and Scarus niger in the Indo-West Pacific exhibit no color differences. However, mature males of Scarus coelestinus and Scarus coeruleus develop more squared-off and prominent foreheads than smaller fish, while Scarus niger exhibits no physical differences other than size. Finally, fleshy tips on the upper and lower lobes of the caudal fin can be observed in mature males of Scarus rubroviolaceus, but are poorly developed on small males and females.
Other Physical Features: ectothermic ; bilateral symmetry
Sexual Dimorphism: male larger; sexes colored or patterned differently; male more colorful; sexes shaped differently; ornamentation
The maximum age of most parrotfishes is less than 20 years and most live less than five years. There is a general trend in the scarids for larger species to live longer. Subsequently, the largest scarid, Bolbometopon muricatum, is the one exception to the 20 year maximum age.
Most parrotfishes exclusively inhabit offshore coral reefs in tropical regions. However, a few species feed primarily on sea grasses and are most common in the Caribbean. Two other species, Nicholsina denticulate and Sparisoma cretense, are common over rocky reefs of the Gulf of California and Mediterranean Sea, respectively.
Habitat Regions: saltwater or marine
Aquatic Biomes: pelagic ; reef ; coastal
Parrotfishes are found primarily in tropical waters throughout the Atlantic, Indian, and Pacific oceans. However, some species inhabit subtropical waters, and some, such as Scarus ghobban, may venture far from reef environments.
Biogeographic Regions: nearctic (Native ); palearctic (Native ); oriental (Native ); ethiopian (Native ); neotropical (Native ); australian (Native ); indian ocean (Native ); atlantic ocean (Native ); pacific ocean (Native ); mediterranean sea (Native )
Parrotfishes are primarily herbivorous, grazing intensively on dead, algae-coated coral, vegetable material, and in some species sea grasses. Bump-headed parrotfishes, which consume significant amounts of live coral, are one exception. Key to the success of parrotfishes is their ability to take up plant material, detritus and calcareous sediment and process it through the action of the pharyngeal jaw. This chewing mechanism grinds ingested material into a fine paste and breaks down algal cells, releasing the cellular material for digestion. Like acanthurids, parrotfishes form large feeding groups, sometimes with multiple species, to overwhelm territorial fishes and deter predators.
Primary Diet: herbivore
Parrotfishes have a major impact on coral reefs through intensive grazing and associated bioerosion. The grazing patterns of large schools of parrotfish have the effect of selecting for certain species of corals and algae, and preventing algae from choking out corals. Many parrotfishes feed on calcareous algae (algae that are high in mineral calcium) growing on dead, exposed coral by biting off chunks and turning them into a fine paste. This type of grazing contributes significantly to the process of bioerosion and the creation of sediment on reefs. For instance, it has been calculated that a single large parrotfish, Bolbometapon muricatum (bump-head parrotfish), consumes approximately one cubic meter of coral skeletons per year, and turns it into fine sediment. In this way large schools of bump-head parrotfish determine the fine-scale topography of coral reefs.
A separate ecological consequence of intense herbivory in parrotfishes is the conversion of plant material into fish flesh. The success of parrotfishes in consuming plant material unavailable to most other fishes and the large size of parrotfish populations makes them an important part of the predatory food chain.
Ecosystem Impact: biodegradation
In the Bahamas, the scales of some parrotfishes are used for decorating basketwork and shellflower arrangements, but the fish are not consumed. In other areas, parrotfishes are sometimes taken as food, but their flesh can be dangerous to humans as a result of accumulated ciguatera toxins.
Positive Impacts: food ; body parts are source of valuable material; research and education
Several species, such as blue parrotfish and one Indo-Pacific species, have caused ciguatera (fish poisoning sickness) in humans, which can be fatal.
Negative Impacts: injures humans
Scarids, which are widely known as parrotfishes because of their beak-like jaws, include approximately nine genera and 83 species. They are abundant in tropical reefs around the world and well known to divers for their striking coloration and noisy feeding as they crunch on dead coral. Parrotfishes exhibit several types of complex mating systems that vary more by geographic location than by species (see Reproduction). They also have considerable ecological impacts on coral reefs through herbivory and bioerosion (see Ecosystem Roles).
Tidal currents disperse parrotfish eggs, which begin to hatch approximately 25 hours after fertilization. Newly hatched larvae begin to feed after three days but the length of the planktonic stage is unknown. Most parrotfish species develop rapidly and reach maturity between two and four years.
One scarid, Scarus guacamaia (rainbow parrotfish), is listed as vulnerable to extinction.
Most known forms of communication in parrotfishes are related to reproduction and are discussed in Reproduction: Mating Systems. However, in some species male coloration intensifies when defending its territory, which suggests that visual cues are used to deter invaders.
Communication Channels: visual ; tactile
Perception Channels: visual ; tactile ; chemical
The fossil history of scarids dates back to the lower Tertiary and Eocene epochs.
Most wrasses are quite small, usually below 20 cm. The smallest species, Minilabrus striatus of the Red Sea, reaches a maximum length of only 4.5 cm. The genera Pseudocheilinus and Doratonotus contain several other dwarf wrasses. One species, Conniella apterygia, is so small that it lacks even pelvic fins and a supporting skeleton. The largest wrasse, Cheilinus undulatus, can reach a length of about 2.3 m and weighs more than 150 kg. Wrasses are most easily identified by their pointed snouts and prominent canine teeth in the front of the jaws, which often project forward. Wrasses characteristically have a protractile mouth, cycloid scales , and a single continuous dorsal fin lacking an obvious notch between the soft and spiny portions. The lateral line may be continuous or interrupted. (Click here to see a fish diagram).
Wrasses display myriad colors and shapes. Razorfishes are elongate and laterally compressed, while members of Cheilinus, Choerodon, and many of Bodianus are large and stocky. However, most are elongate and tapered at both ends, often referred to as “cigar-shaped.” Cigar-shaped fishes are found in the genera Thalassoma, Halichoeres, and Labroides. Often, there is considerable diversity of colors and shapes within individual species. As in parrotfishes, some wrasses progress through “phases” (see Reproduction: Mating Systems), and each phase corresponds with a change in morphology (shape and color). Dominant males (and sometimes females) are the most distinctly colored, with complex patterns of red, yellow, green, blue and black. Subordinate males and females are smaller than dominant individuals and are often drab-colored with cryptic patterns. Juveniles range in coloration from bright yellow and orange to drab gray and brown, and some have camouflaging patterns. (See Reproduction: Mating Systems for details). Some wrasses exhibit sexual dimorphism.
Other Physical Features: ectothermic ; bilateral symmetry ; polymorphic
Sexual Dimorphism: male larger; sexes colored or patterned differently; male more colorful; sexes shaped differently
No information was found concerning the lifespan of wrasses but, in general, reef species live between three and five years.
Wrasses can be found in a wide variety of habitats, such as tidal pools, grass beds, rocky or coral reefs, or open sand bottoms. Many wrasses prefer specific environments. Doratonotus, for example, prefer turtle grass beds, Hemipteronotus, mixed turtle grass and sandy patch areas, and hogfishes, weed-covered rocky flats. Plankton feeders, such as Clepticus, often concentrate in large schools at reef fronts, reef gaps, or other areas where plankton is concentrated in the water column. However, some species, such as the slippery dick, can be found in a broad range of habitats.
Habitat Regions: temperate ; tropical ; saltwater or marine
Aquatic Biomes: benthic ; reef ; coastal ; brackish water
Other Habitat Features: estuarine ; intertidal or littoral
Wrasses occupy all tropical seas and penetrate considerable distances into temperate waters, reaching as far north as Norway. Many temperate species in the genera Oxyjulius, Tautoga, Tautogolabrus, Semicossyphus, and Labrus can be found in both the Atlantic and Pacific Oceans. Wrasses are most highly concentrated off the coasts of Australia where about 165 species and 42 genera are represented.
Biogeographic Regions: nearctic (Native ); palearctic (Native ); oriental (Native ); ethiopian (Native ); neotropical (Native ); australian (Native ); oceanic islands (Native ); indian ocean (Native ); atlantic ocean (Native ); pacific ocean (Native ); mediterranean sea (Native )
Many wrasses are specialized and voracious feeders, as reflected by the highly variable skull and body shape, modified pharyngeal jaw, and prominent canines. The type of nourishment ranges widely: fish, ectoparasites, mollusks, polychaete worms, decapod crabs, corals, coral mucous, amphipods, various echinoderms, plankton, and several types of vegetation. Many small wrasses follow larger fishes and exploit any benthic (reef bottom) disturbances that help to reveal the well-camouflaged invertebrates. A considerable number are plankton feeders, forming schools in reef gaps, reef fronts or other areas with current. The food habits of cleaner wrasses are probably most well known. Cleaner wrasses remove mucous, parasites and scales from the bodies of larger fishes. Cleaning is not limited to the Labroides genus however; young bluehead and young Spanish hogfish in the Bahamas have also been observed cleaning larger fishes. Finally, some piscivorous (fish-eating) wrasses mimic harmless fishes (Randall and Kuiter, 1989 in Nelson, 1994).
Primary Diet: carnivore (Piscivore , Eats eggs, Eats body fluids, Eats non-insect arthropods, Molluscivore ); herbivore ; omnivore
The ecological role of cleaner wrasses of the Indo-Pacific region provides a good example of the complexity of seemingly mutualistic relationships between fishes. Typically, cleaner fishes are elaborately colored and perform displays over a patch of reef while larger fish approach and assume a relaxed posture. Cleaner fishes are commonly thought to benefit the host by removing dead or damaged tissue and ectoparasites. Accordingly, investigators reported higher recovery rates for wounded fish in the presence of cleaners. However, in experiments where all cleaners were removed from an environment there was no incidence of fishes leaving the area or becoming particularly unhealthy. Further, when levels of parasitic infections are high the host benefits from cleaning but when infection levels are low, which they usually are, some cleaners feed on healthy tissue, such as scales, pieces of fin, mucous, or in some cases the eggs of other reef fishes. Despite these parasitic qualities of the relationship, fishes being cleaned have a positive response to the tactile stimulation from cleaners, suggesting that some cleaners are mildly beneficial while others have taken advantage of the cleaning arrangement.
The relationship between wrasse species and their invertebrate prey is a spectacular example of coevolution. As invertebrates have developed anti-predator adaptations, such as spines, toxins, heavy armor, and adherence to the substrate, wrasses have evolved simultaneously. Some physical changes include the development of strong, hard beaks and a second set of strong teeth in the throat ( pharyngeal jaw), making it possible to crush hard-shelled invertebrates. A conspicuous behavioral adaptation is “following behavior.” As larger fish disturb the substrate, some wrasses follow close behind to capture exposed invertebrates. Other small wrasses have become adept at combing the reef for invertebrates too small for most fishes to prey upon. Finally, some wrasses use their snouts to flip rocks and pieces of coral to expose hidden invertebrates.
Ecosystem Impact: parasite
Species Used as Host:
Mutualist Species:
Wrasses from the Coris genera are popular aquarium fishes and two species from the Atlantic coast of North America, the cunner and the tautog, are valued as commercial and sport fish. Some other medium to large wrasses are popular food fishes as well.
Positive Impacts: pet trade ; food ; research and education
No specific information was found concerning any negative impacts to humans.
Wrasses (the family Labridae), are the most abundant and conspicuous fishes on tropical reefs around the world. Wrasses also comprise an important element of the coldwater fish population on temperate reefs. They are second largest family of marine fishes and the third largest family in the Perciformes order, containing approximately 60 genera and roughly 500 species. Wrasses appear in a diverse range of colors, shapes, and sizes, often varying considerably within individual species (see Physical Description). This morphological diversity is matched by the wide variety of prey consumed. Wrasses fill the roles of piscivores, zooplanktivores, molluscivores, herbivores, planktivores, polychaete predators, decapod crab predators, and coral predators, as well as many others (see Food Habits). Many wrasses are organized into harem-based social systems and hermaphroditism is common (see Reproduction: Mating Systems). Finally, as suggested by their diverse food habits, wrasses fill many important ecological roles on reefs of tropical and temperate regions around the world.
Wrasses occupy a wide range of water temperatures and incubation time is directly affected by water temperature. In laboratory experiments incubation took approximately 24 hours at 27˚C. The planktonic stage is estimated to be around one month, although very little is known about this stage. The age or size at which individuals reach sexual maturity depends on the maximum size of the species.
Four labrid species are listed as vulnerable: Cheilinus undulates, Lachnolaimus maximus, Thalassoma ascensionis, and Xyrichtys virens.
Most wrasses rely on vision to find their prey. Visual recognition may also be important for terminal phase (TP) males to identify harem members. Although TP males are susceptible to streaking attempts by initial phase (IP) males (see Reproduction: Mating Systems), no IP males have been found in harem-forming species. This suggests that IP males are unable to mimic IP females, despite very similar morphology.
Communication Channels: visual
Other Communication Modes: mimicry
Perception Channels: visual ; tactile ; chemical
The fossil history of Labridae dates back to the lower Tertiary and Paleocene epochs.
Like parrotfishes, many wrasses utilize some of the most complex and unusual reproduction systems known to fishes. Males can be either primary (born male), or secondary (females that have undergone sex change). In some species there are no secondary males while in others all individuals are born female (monandric) and change sex when necessary. In the most complex systems, species are diandric – both primary and secondary males exist in the population. In these species, individuals proceed through three distinct phases, marked by color differences. In fact, the color differences are so pronounced that for over 200 years researchers regarded some phases as distinct species. Sexually immature juveniles represent the first phase. The second, known as the initial, phase (IP) can include sexually mature males or females, which are impossible to tell apart without internal examination or observation during spawning. IP males and females may group spawn in some species. The terminal phase (TP) includes only mature males, which display brilliant colors. TP males usually dominate reproductive activity through a harem-based social system. The death of a TP male serves as a social cue for an IP female to change sex and behavior. The morphology of IP males may also change in response to the death of a TP male. In some cases, IP males attempt to fertilize IP females by following a TP male and IP female pair during spawning. In this behavior, called “streaking,” IP males follow the pairs at peak spawning and release a large cloud of gametes in an attempt to overwhelm fertilization by the TP male. This is thought to increase the fecundity (ability to produce offspring) of IP males. IP males are well equipped to perform streaking as they have larger gonads and so are able to produce more gametes, while TP males have smaller testes and rely on aggression to deter other males. The larger volume of milt (gametes) produced by IP males is related to group spawning events with IP females, in which competition for fertilization is intense and more milt is needed.
Some specific examples of wrasse mating systems demonstrate the complexity and variation of the phase system described above. For instance, the cleaner wrasse, which is monandric (all individuals are born female), forms harems that are held together by male aggression towards subordinate females. With the death of the dominant male, subordinate females jockey for position and the newly dominant female adopts aggressive male behavior within a few hours. Each individual moves a step up in the dominance hierarchy and the last position is filled by a juvenile. If the newly dominant female is able to withstand attempts by neighboring males to take over the vacant harem, she will become a fully functional male within a two to four days. Some other harem-forming species are Cirrhilabrus temminckii, Cirrhilabrus jordani, Labroides bicolor, Hemipteronotus splendens, Pseudocheilinus hexataenia and Macropharyngodon moyeri. The Caribbean species Halichoeres garnoti is also monandric, but individuals do not exhibit territoriality or conspicuous dominance relationships, nor do they use aggressive actions to maintain sexual state. Instead, size or some size-related factor determines which individual will fill the male role. In Halichoeres garnoti males are larger than females and both sexes behave similarly. While these examples focus on the mating extremes of wrasses, most species fall between the systems of the cleaner wrasse and Halichoeres garnoti in terms of the influence of social control on sex reversal. Other hermaphroditic but non-harem-forming species include Halichoeres bivittatus and Halichoeres poeyi, Halichoeres maculipinna and possibly Thalassoma lunare. Finally, some species, such as Oxyjulis californica and Crenilabrus melops, do not follow the phase system at all as they are not hermaphroditic, and there are probably more non-hermaphroditic species yet to be found.
Mating System: polygynous ; polygynandrous (promiscuous)
In tropical wrasses spawning occurs year-round but some temperate species seem to restrict spawning to warmer parts of the year. Spawning typically occurs along the outer edge of patch reefs or along the outer edges of more extensive reef complexes. The correlation between spawning and lunar periodicity (the lunar cycle) is sketchy in some species and non-existent in most that have been investigated. Spawning in several species corresponds with outgoing tides, however, many species spawn at a particular time in the day, regardless of tidal patterns. This variation may be due to local conditions. For instance, in areas where tidal forces are weak, factors like time of day or light intensity may have more influence. However, evidence from different species on the same reef suggests that temporal (measured time) differences in spawning evolved to decrease the probability of hybridization with other species.
Wrasses may spawn in groups or pairs depending on the species or phase of individuals. Typically, group or aggregate spawning occurs between initial phase (IP) individuals, which are diandric (containing male and female IP individuals). However, in some species, such as Thalassoma cupido, Thalassoma lucasanum, and Halichoeres bivitattus, terminal phase (TP) males have been observed participating in group spawning. The size of the spawning groups ranges from a dozen to several hundred individuals. Males outnumber females, sometimes by as much as ten to one. Paired spawning is found in many, if not all, tropical wrasses and involves a TP male and IP female. In rare cases, IP individuals also spawn in pairs. Most species defend small territories only during spawning. Currently Anampses cuvieri is the only known species of tropical wrasse to produce demersal eggs (eggs laid on the bottom as opposed to being released in the water column). Demersal spawning of Anampses cuvieri was only observed in captivity and still needs to be confirmed, but work on other species of this genus seems to support this observation.
Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sequential hermaphrodite (Protogynous ); sexual ; fertilization (External ); oviparous
Some temperate wrasse species, such as the ballan wrasse and Anampses cuvieri, are demersal nest builders. The nests are usually made out of plant material and the male guards the eggs after they are deposited.
Parental Investment: male parental care
Parrotfishes utilize some of the most complex and unusual reproduction systems known to fishes. Males can be either primary, i.e. born male, or secondary, i.e. females that have undergone sex change. In some species there are no secondary males while in others all individuals are born female (monandric) and change sex when necessary. In the most complex systems, species are diandric – both primary and secondary males exist in the population. In these species, individuals proceed through three distinct phases, marked by color differences. In fact, the color differences are so pronounced that for over 200 years researchers regarded some phases as distinct species. Sexually immature and drab colored juveniles represent the first phase. The second, known as the initial, phase (IP) can include sexually mature males or females, which are impossible to tell apart without internal examination or observation during spawning. The terminal phase (TP) includes only mature males, which display brilliant colors. TP males usually dominate reproductive activity through a harem-based social system. The death of a TP male serves as a social cue for an IP female to change sex and behavior. The morphology and behavior of IP males may also change in response to the death of a TP male. In some cases IP males attempt to infiltrate a TP male’s harem by masquerading as a female. In the so called “sneak spawning” attempt IP males follow spawning pairs into the water column and release a large cloud of gametes at peak spawning in an attempt to overwhelm fertilization by the TP male. IP males are well equipped to perform “sneak spawning” as they have larger testes and so are able to produce more gametes, while TP males have smaller testes and rely on aggression to deter other males.
The type of reproductive behavior described above and whether it involves paired, foraging group or mass spawning depends on a complex set of behavioral and geographic factors. For instance, some species, such as Scarus iseri, exhibit a wide range of reproductive behaviors depending on the area in which they are found. In Panama, Scarus iseri employs a system involving three classes of individuals: territorials, stationeries and foragers. Territorials are organized into groups that consist of a dominant female, several subordinate females and usually, but not always, a terminal (TP) male. Paired spawning occurs within the territory, which both males and females defend. Stationaries consistently use the same area for spawning but do not defend it, and foragers include groups of up to 500 individuals, mostly females. In Puerto Rico, initial phase (IP) and terminal phase (TP) individuals migrate to temporary spawning areas in deep water, usually in pairs. Finally, in Jamaica Scarus iseri emphasizes aspects of the foraging group system and spawning only takes place in groups. The three previous examples illustrate the flexibility of the socio-sexual mating systems found in parrotfishes. The reasons that different aspects of the basic spawning system manifest in different areas range from population density to competition for spawning sites and other resources to geographic factors like seasons and water temperature.
Mating System: polygynous ; polygynandrous (promiscuous)
In general, parrotfishes spawn year-round, usually at dusk. However, peak spawning occurs in summer for many species and there is evidence that some species have defined non-spawning periods. As discussed above, many species migrate to the outer edges of the reef to spawn but some spawn within defined territories. There is evidence that some scarids respond to the lunar cycle during spawning, but in others, spawning correlates closely with high tide, regardless of the time of the lunar month. In species that spawn several times during the day, the tidal cycle is followed closely since this is the optimal time for egg dispersal.
Key Reproductive Features: iteroparous ; seasonal breeding ; year-round breeding ; sequential hermaphrodite (Protogynous ); sexual ; fertilization (External ); oviparous
There is no evidence of parental behavior in parrotfishes.
Parental Investment: no parental involvement
The wrasses are a particularly diverse and abundant family of reef fishes, with numerous species that occupy essentially all reef, rock, and grassbed habitats in the Caribbean. The bluehead wrasse, Thalassoma bifasciatum, is the single regional representative of a prominent labrid genus and is ubiquitous on Western Atlantic coral reefs. Another large genus of wrasses, Halichoeres, has more than 80 species throughout the tropics with many regional representatives, not all of which are closely related. There are three local razorfishes in Xyrichtys (note that Xyrichtys is frequently misspelled as Xyrichthys) and two hogfishes in Bodianus. The remaining labrid genera in the region are mostly monotypic: Doratonotus megalepis, Lachnolaimus maximus, Clepticus parrae, and the deep-water wrasse Decodon puellaris (the latter two species have a sibling species in the eastern Atlantic and in the eastern Pacific, respectively).
Labrid larvae can be recognized by the absence of head spines, long and continuous dorsal and anal fins with slender spines, a relatively wide caudal peduncle, stub-like pelvic fins, a pointed snout with a small terminal mouth and typically light markings (none or melanophores mostly on the fin-ray membranes). Notably, there is no row of melanophores along the anal-fin base, which separates labrid larvae from many similar-appearing groups, such as larval scarids, labrisomids, chaenopsids, dactyloscopids, and gobies. While most tropical labrid larvae fit this general pattern of small and mostly unpigmented larvae, two genera are exceptions: larval Lachnolaimus maximus are fully-pigmented and Decodon melasma have an unusual and large late larval stage with a pattern of bars on the body.
While genera are relatively easily distinguished, congeneric labrid larvae can appear similar, if not identical. Several species of Halichoeres share melanophore patterns and only become recognizable to species during transition. Larval razorfishes, Xyrichtys, have no melanophores and do not diverge in appearance until juvenile markings develop (however their evanescent chromatophore patterns may be species-specific). Some Caribbean labrid larvae require DNA sequencing for identification to species.
The labrids below are presented in order of increasing numbers of dorsal-fin spines: from 8 to 14 in the regional labrids. Fin-ray counts generally separate Caribbean genera well.
The Odacidae are a small family of ray-finned fishes commonly known as cales and weed whitings, formerly classified within the order Perciformes. They are related to the much larger families of the wrasses and parrotfish.[2] More recent workers have classified this family within the order Labriformes, alongside the wrasses and parrotfishes, within the clade Percomorpha.[3]
Odacids are found in coastal waters off Southern Australia and New Zealand. They include species that feed on small invertebrates, as well as herbivorous grazers, some of which are able to feed on chemically unpleasant varieties of kelp otherwise unpalatable to fish.[2]
The following genera are classified in the family Odacidae:[4]
Fishbase places six species in the genus Siphonognathus.[5] Catalog of Fishes, in contrast, places four of the six species in the separate genus Sheardichthys and places S. caninis in the monospecific genus Parodax, leaving Siphonognathus as a monospecific genus containing only S. argyrophanes.[6]
The Odacidae are a small family of ray-finned fishes commonly known as cales and weed whitings, formerly classified within the order Perciformes. They are related to the much larger families of the wrasses and parrotfish. More recent workers have classified this family within the order Labriformes, alongside the wrasses and parrotfishes, within the clade Percomorpha.
Odacids are found in coastal waters off Southern Australia and New Zealand. They include species that feed on small invertebrates, as well as herbivorous grazers, some of which are able to feed on chemically unpleasant varieties of kelp otherwise unpalatable to fish.
