Labroidei II

(Damselfishes, wrasses, parrotfishes, and rock whitings)

Class Actinopterygii

Order Perciformes

Suborder Labroidei

Number of families 4

Evolution and systematics

The four families in this grouping are part of the suborder Labroidei. The families are: Labridae (the wrasses); Scaridae (the parrotfishes); Pomacentridae (the damselfishes); and Odacidae (the rock whitings, or butterfishes, of western Pacific waters; the butterfishes of North America represent a different family).

The family Labridae is a large one, with approximately 500 species in 60 genera. The next largest of the four families is the Pomacentridae, with more than 320 species in 28 genera, followed by the Scaridae, with 83 species in 9 genera, and finally the Odacidae, with 12 species in 4 genera.

The taxonomy of these four families is under dispute, and several studies are under way to iron out the relationships. In fact, some taxonomists feel the scarids and odacids, which are believed to have evolved from labrids, should actually be listed as subfamilies within Labridae. Other researchers have focused their work on the evolutionary relationships among genera within families. As the genetic makeup of individual species becomes a more prominent tool in defining evolutionary relationships, there is little doubt that some shaking looms ahead for these branches of the tree of life.

Physical characteristics

This grouping of fishes is varied, but vibrant color is a trademark of many species in the four families, and has made wrasses and damselfishes the highlights of reef-diving excursions. In addition, the scarids, labrids, and odacids all share unusual pharyngeal modifications that serve as additional chewing surfaces to grind kelp, hard-shelled invertebrates, and other dietary items.

Generalizations can also be made about each of the four families. Most labrids, or wrasses, have gapped and outwardprojecting teeth on protrusible upper and lower jaws. The dorsal fin typically has less than 15 spines; some have as many as 21 spines and 6–21 soft rays. The anal fin has 4–6 spines and 7–18 soft rays. Other than these characteristics, little else is noticeably uniform among this highly diverse family. Maximum adult size in the family ranges from about 2 in (5 cm) in a variety of species, to more than 8 ft (2.5 m) in the humphead wrasse (Cheilinus undulatus).

The pomacentrids, or damselfishes, are characterized by a deep, compressed body; a small mouth with short canine teeth; a usually two-spined anal fin; one dorsal fin with spines numbering 8–17, and 10–18 rays; and a lack of teeth on the palate. Maximum adult size ranges from 1.6 in (4 cm) in some Chromis and Chrysiptera species, to over 12 in (30 cm) in the garibaldi (Hypsypops rubicundus) and giant damselfish (Microspathodon dorsalis).

Scarids, or parrotfishes, have a rather distinctive "parrot's beak" resulting from a fusion of the teeth and often fleshy lips. The dorsal fin has 9 spines and 10 soft rays, the anal fin has 3 spines and 9 soft rays, and the pectoral fin has one spine and 5 soft rays. Large scales are evident even from some distance.

The small Odacidae family is still quite diverse, and is occasionally described as being intermediate between the scarids and labrids. The jaw teeth are fused in a manner similar to the parrotfishes, but they have a different dorsal fin pattern, with 12–23 spines, compared to the 9 spines in scarids. Odacids, the rock whitings or butterfishes, have the more elongate body seen in many labrids, but do not have the protrusible jaws.

Distribution

Parrotfishes, wrasses, and damselfishes occupy mainly tropical, marine waters of the Atlantic, Pacific, and Indian Oceans, but some species, particularly wrasses, extend well into cooler waters, and a few damselfishes exist in estuaries and occasionally venture into fresh water. The rock whitings are found in the temperate, coastal waters of Australia and New Zealand.

Habitat

This group comprises primarily reef-associated fishes, although a few make their homes in the open sea. The reefs

provide a source of refuge, as many of the species use the nooks and crannies in the coral as daytime hiding places from predators. A number of species also gain nourishment directly from the coral by nipping off polyps and grinding them with their pharyngeal jaws. Some species, particularly the juveniles, prefer the shallower, protected waters of lagoons and bays, and the adults of many reside in waters of steep, outer, reef slopes.

A number of parrotfishes live among beds of sea grass or in rocky reefs, and wrasses frequently require living coral reefs, but some do very well among dead coral. Damselfishes generally live in rocky and coral reefs, but individual species may prefer open water as deep as 300 ft (91 m) or more, or shallow habitats of as little as 12 ft (3.7 m) in either the open sea or in sheltered areas with calmer waters. Some species within these four families prefer very specific habitats. Anemonefishes (genera Amphiprion and Premnis), for example, may require the presence of a particular species of anemone.

Behavior

Two of the most well-known behaviors of this group of fishes involve that of certain damselfishes and their symbiotic relationship with large sea anemones, and that of parrotfishes, which produce a mucus "cocoon" that surrounds them while they sleep at night.

Known as anemonefishes, or clownfishes, the 30 damselfishes in the genera Amphiprion and Premnas move among and between the dangerous tentacles of the sea anemone, even sleeping within them. Stinging cells (nematocysts) on the surface of the tentacles normally sting and paralyze prey fish for easy consumption by the anemone. The anemonefishes, however, live peacefully among the anemones. Current consensus is that a protective mucus coat on the anemonefish shields it from the sting of the tentacle. The relationship is symbiotic because both species gain from it. The anemonefish receives shelter from predators, while helping to maintain the health of the anemone by picking off organisms and detritus from its tentacles. The relationship is more important to the anemonefishes than to the anemones, because the fishes are unable to escape predation without the sanctuary of the anemone, but anemones can and do survive in the absence of the fishes.

Parrotfishes, on the other hand, have their own presumably protective behavior. At night, these diurnal animals prepare for sleep by generating a tube of mostly clear mucus that surrounds the body. The tube forms in about 30–60 minutes. There is some debate over whether cocoon formation is a behavioral trait or simply the result of normal mucus secretions that accumulate because the fish is stationary. Either way, the mucus tube appears to provide the fishes with some protection from predators by masking them, and perhaps by surrounding them with an unpleasant-tasting barrier.

Feeding ecology and diet

Herbivores and carnivores exist within this group, with the diet of many species comprising both plants and animals.

Feeding habits vary. The odacids are mainly herbivores, with a few dining on kelp, a coarse seaweed shunned by most other species. One study of the butterfish Odax pullus showed that this herbivorous odacid has an active symbiotic relationship with gut microbes that assists in the digestion of the plant matter. Several damselfishes hold feeding territories and even cultivate algal beds. Many scarids and odacids are herbivorous grazers, using their parrotlike beaks to scrape algae from rocks and coral, or to crush open a hard-shelled invertebrate, such as a mussel or sea urchin. A few even eat coral polyps. Some parrotfishes are so aggressive in their feeding habits that they are considered a cause of reef erosion, as they not only alter the reef, but also excrete a great deal of silty sediment that coats the reef structure. As a rule, species that dine on coral, mollusks, and other crunchy prey have more rounded teeth attuned to grinding. The teeth of species that favor softer dietary items are more pointed.

The wrasses are primarily carnivores, and generally choose from a variety of hard-shelled, invertebrate prey. Some, however, prefer that their food come to them, and take their diet of plankton from the water column. One of the most unusual feeding behaviors in this group is seen in the cleaner wrasses.

This group of small fishes in the genus Labroides have specific sites where they provide cleaning services to other fishes. Fishes come to these so-called cleaning stations, and announce their desire to be cleaned by exhibiting stereotyped behaviors through movements of their mouths or bodies. The cleaner wrasses strike a deal by responding with their own behaviors, including brushing the "client" with their fins, and the cleaning begins. The wrasses pick over the body, fins, and head of the client fish, and may even enter the gill chamber and mouth to remove crustacean ectoparasites, mucus, dead skin, dislodged scales, and other detritus. Both client and wrasse benefit from the arrangement: the cleaner is fed, and the client is cleaned.

Other wrasses also provide cleaning services, particularly juveniles of the genus Thalassoma. A study of Noronha wrasse (T. noronhanum) and a client fish, the piscivorous coney (Cephalopholis fulva) indicated that client fishes sometimes take advantage of the situation and eat the cleaner. In this study, scientists observed predation in two instances, both of which occurred when the wrasse was tending the coney away from its normal cleaning station.

Fishes in these four families may fall prey to larger bony fishes. The primary predators include larger serranids, synodontids, aulostomids, and members of other families.

Reproductive biology

Perhaps most notable characteristics of this group of fishes are the three separate color phases and sex reversal associated with many species. The typical three-phase lifestyle begins with a juvenile (immature) phase, then an adult initial phase, and finally the terminal phase. Each has a distinctive appearance that differs from species to species. In the bluehead wrasse (Thalassoma bifasciatum), for example, juveniles are bright yellow, initial-phase adults are yellow with black stripes, and terminal-phase males are deep blue with a green rear and midbody, and bold, black and white bands behind the head. The initial-phase adults in many species are almost all females, and in most cases, the few initial-phase males look the same as their female counterparts. The initial and terminal phases are usually so different that inexperienced divers

frequently assume they are two species. This three-phase lifestyle is characteristic of the wrasses and parrotfishes. Damselfishes typically shift gradually from a colorful juvenile pattern into a the more drab suit of an adult.

Along with the three color phases in the parrotfishes and wrasses, these two families engage in sex reversal. Here, the initial-phase adults usually are mostly female, often living in a small grouping, or harem. Each harem has one terminal-phase male, which mates with the adult females. The females form a hierarchy within the harem, with one dominant female followed by a second-ranking female, a third, and so on. If the male is removed from the group through predation or other means, the dominant female steps up to become, socially and physiologically, the terminal-phase male. The social change can occur in as little as a few hours. The physiological change, including the development of functional testes, may take a couple of weeks. The hierarchy among the females continues, with the second-ranking female moving into the position of dominant female, and the rest moving up a step in the hierarchy.

Initial-phase males are also capable of becoming the terminal-phase male, and this frequently occurs in nonharemic groups. In this reproductive arrangement, the terminal-phase males set up a territory where females may enter for one-on-one mating. When the terminal-phase male is removed, an initial-phase male or female may take his place. Another reproductive strategy is available for initial-phase males, which are sexually mature. Initial-phase males will form schools, and chase individual females as they make their way to a terminal male's territory, and "sneak-spawn" with them. Although sole paternity is out of the question for individual sneak-spawners, at least the initial-phase male can add his milt to the mix and perhaps fertilize a few eggs. Many of these fishes also engage in mass spawning, in which both terminal-phase and initial-phase males participate.

Damselfishes may not have the obvious phase differences, but they do have interesting reproductive behavior. As a group, these fishes are quite territorial of their mating sites and will mount vicious attacks on intruders, complete with rushes, grunts, and bites. The male typically clears a nest site, engages in ritualistic visual and tactile displays to attract a female, mates, and then cares for the eggs until they hatch, when the young are on their own. In an unusual twist, the marine damselfish (Acanthochromis polyacanthus) continues its care of the young for several months after hatching. Anemonefishes are noted because they reverse gender like the parrotfishes and wrasses, but in the opposite direction. In an anemone, this species exists in small groups with one large female, one large male, and several small, immature males. Should the large female be removed, the most-dominant immature male can develop to take her place.

Little is known about reproduction in odacids overall, but the butterfish O. pullus does change sex from female to male and exists in small harems. Females lay their eggs directly into a plankton column.

Conservation status

Eight species are included on the IUCN Red List, all of them categorized as Vulnerable. The eight species are: in the Pomacentridae, Chromis sanctaehelenae, Stegastes sanctaehelenae, and S. sanctipauli; in the Labridae, Cheilinus undulatus, Lachnolaimus maximus, Thalassoma ascensionis, and Xyrichtys virens; and in the Scaridae, Scarus guacamaia.

Significance to humans

Aesthetic, particularly to divers, and often popular in the aquarium trade. A few are minor commercial food fishes.

Species accounts

List of Species

Humphead wrasse

Cheilinus undulatus

family

Labridae

taxonomy

Cheilinus undulatus Rüppell, 1835, Jidda, Saudi Arabia, Red Sea.

other common names

English: Maori wrasse, Napoleon wrasse; French: Napoléon; Spanish: Napoleón.

physical characteristics

Length 5 ft (about 1.5 m), although a few have been recorded at more than 8.2 ft (2.5 m); one of the largest reef fishes. The large adult has distinctive hump on the top of the blue-fronted, small-eyed, thick-lipped head; rest of the body is yellowish green. Juveniles pale green, with horizontally placed spots or bar extending down the sides of the body.

distribution

Much of the Red Sea and Indian Ocean, east through Indonesia to Tuamotus, French Polynesia, and north to southern Japan.

habitat

Juveniles frequent sea grass beds and reef lagoons. Adults prefer deeper reef areas to 325 ft (100 m) deep.

behavior

Shy, diurnal, remains among reef refuges at night. Usually solitary, but will sometimes live in pairs or in small groups.

feeding ecology and diet

Feeds during the day, primarily on mollusks, but also takes fishes, as well as other invertebrates such as brittle stars and sea urchins.

reproductive biology

Both small and large spawning aggregations form, but fishes pair up for mating. No parental care. Sex reversal has been noted, in which females develop into mature males.

conservation status

Listed as Vulnerable by the IUCN.

significance to humans

Commercial food fish whose intensive exploitation has led to concern for the survial of local populations of this species. Also popular aesthetically to divers.

Bluestreak cleaner wrasse

Labroides dimidiatus

family

Labridae

taxonomy

Labroides dimidiatus Valenciennes, 1839, El Tûr, Sinai Coast, Egypt, Gulf of Suez; Mauritius.

other common names

English: Bridled beauty, cleaner wrasse; French: Bande bleue, nettoyeur à poisson doctère, poisson nettoyeur commun.

physical characteristics

Total length 4.5 in (11.5 cm). Adults mostly light blue, with long black stripe running along each side of body, widening as it approaches the tail. Juveniles black with blue dorsal stripe.

distribution

Throughout the Indo-Pacific region, west to the Red Sea and East Africa, north to the southern tip of Japan, and as far east as the Marquesas and Ducie Islands in the south central Pacific Ocean.

habitat

Prefers coral reef areas from surface waters to 130 ft (40 m) deep.

behavior

Known for its cleaning habits, picking at and removing ectoparasites and assorted detritus on various species of fishes. Individuals or pairs set up stations, where they remove material from the bodies, gills, and even mouths of their "clients." Stereotyped signals between the two fishes help ensure that the cleaning goes smoothly, and the cleaner does not end up as the client's dinner.

feeding ecology and diet

Attains bulk of the diet from ectoparasites and detritus on other fishes.

reproductive biology

Sometimes lives in pairs, but frequently in harems of one dominant male and 6–10 females. Sex reversal occurs when dominant

male is removed from a harem. The dominant female assumes his place, and becomes a functional male in about two weeks.

conservation status

Not listed by the IUCN.

significance to humans

Common aquarium fish.

Hogfish

Lachnolaimus maximus

family

Labridae

taxonomy

Lachnolaimus maximus Walbaum, 1792, type locality not specified (probably Bahamas or Carolinas).

other common names

French: Labre capitaine; Spanish: Doncella de pluma.

physical characteristics

Total length 36 in (91 cm). Often mottled, light orangey brown, but can adjust its color to match immediate surroundings. Adult dorsal fin sports three unusually long spines on anterior end. Dark stripe extends through eye to base of dorsal fin just behind head.

distribution

Bermuda, along the Atlantic coast of the Americas, from Nova Scotia to northern Venezuela, and into the southern and eastern Gulf of Mexico.

habitat

Sandy reef areas.

behavior

Males are territorial, holding narrow areas about 100 yards (90 m) long. Around a dozen females share the territory with the male.

feeding ecology and diet

Prefers mollusks, crabs, and other hard-shelled invertebrates. Diurnal; during feeding ejects water streams into substrate to root out buried invertebrates.

reproductive biology

Sex reversal is common. All fishes begin life as females, which can develop into males. No parental care is given to the pelagic eggs.

conservation status

Listed as Vulnerable by the IUCN.

significance to humans

Commercial food fish. The large adult size and relatively sedentary character of this species make it particularly vulnerable to overharvesting.

California sheephead

Semicossyphus pulcher

family

Labridae

taxonomy

Semicossyphus pulcher Ayres, 1854, San Diego, California, United States.

other common names

French: Labre californien; Spanish: Vieja de California.

physical characteristics

Length 36 in (91 cm). Large teeth are a trademark. Initial-phase adults are orange with a white chin, terminal-phase

adults retain orange coloration at midbody at white chins, but have black heads and rear bodies.

distribution

Subtropical waters in the Gulf of California, and off the west coast of North America, from Monterey Bay in central California, United States, south about 600 mi (966 km) to Guadalupe Island, Mexico.

habitat

Lives among kelp beds, in shallow, rocky-bottomed waters.

behavior

Sex reversal is common, with females developing into males as they grow older.

feeding ecology and diet

Feeds on mollusks, crabs, sea urchins, and other invertebrates.

reproductive biology

Protygynous, mating takes place each summer. No parental care.

conservation status

Not listed by the IUCN.

significance to humans

Commercial food fish.

Bluehead

Thalassoma bifasciatum

family

Labridae

taxonomy

Thalassoma bifasciatum Bloch, 1791, East India (actually western Atlantic).

other common names

English: Bluehead wrasse, tiki tiki; Spanish: Cara de cotorra.

physical characteristics

Length 9.9 in (25 cm). Begins life as yellow, eventually develops black, horizontal stripes. Large terminal-phase males have vivid blue heads followed by white and black vertical bands, then green rear bodies and a bluish tail.

distribution

Western Atlantic Ocean near Bermuda, also from northern South America to the West Indies and southern Florida, United States, and into the Gulf of Mexico.

habitat

Coral reefs. Also seen among sea grass beds.

behavior

Juveniles often provide cleaning services to other fishes. Among adults, spawning occurs differently depending on the size of the reef. On large reefs, group spawning is the rule. On small reefs, terminal-phase males utilize mating territories. Males from ensuing generations frequently use their ancestral mating site, apparently as a result of social convention. Dozens of females may select the same spawning site, and thus mate with the same male. Groups of smaller males often mate with egg-laden females by ambushing them on their way to the territorial mating sites.

feeding ecology and diet

Primarily feeds on drifting zooplankton, but also takes crabs, shrimps, sea urchins, and sea stars. Sometimes engage in cleaning of other species.

reproductive biology

Engage in sex reversal. Over a period of several weeks, the black-striped, yellow males or females take on full coloration of large, terminal-phase males. Initial-phase females can take on the role of the terminal-phase male and begin producing sperm in as few as eight days.

conservation status

Not listed by the IUCN.

significance to humans

Aquarium fish.

Butterfish

Odax pullus

family

Odacidae

taxonomy

Odax pullus Forster, 1801, Queen Charlotte Sound, New Zealand.

other common names

English: Greenbone; Maori: Mararii.

physical characteristics

Length up to 27.5 in (70 cm). Long dorsal fin begins just behind head, becoming increasingly wide as it draws to its posterior end. Males bluer than females, and have longer dorsal and anal fin tips.

distribution

Throughout New Zealand waters, with fisheries in the area of Cook Strait and Stewart Island.

habitat

Mostly occurs near the surface to 33 ft (10 m) deep, in waters heavy with kelp. Some live in sheltered areas, others prefer tidal zones.

behavior

Diurnal, lives in small groups of one male and several females.

feeding ecology and diet

Adults move into more open reefs at dawn to begin grazing on red, green, and brown algae, particularly kelp, which they clip with beak-like mouths, then grind with pharyngeal jaws. Juveniles eat red algae and crustaceans.

reproductive biology

Begins life as a female, and reverses sex as it matures. Mating occurs several times each year between females and territorial males, from late winter to early spring. A pelagic spawner.

conservation status

Not listed by the IUCN.

significance to humans

Sportfish and minor commercial food fish.

Clown anemonefish

Amphiprion ocellaris

family

Pomacentridae

taxonomy

Amphiprion ocellaris Cuvier, 1830, Sumatra, Indonesia.

other common names

English: Common clownfish, false clown anemonefish.

physical characteristics

Total length 4.3 in (11 cm). Distinctive orange fish with three wide, vertical, white bands encircling the body just behind the eyes, at midback and in front of the tail. The fins and rounded tail are outlined in black, then edged in grayish white. Similar in general appearance to A. percula.

distribution

Coastal waters surrounding Indonesia; north and west to Burma, north and east past the Philippines to southern Japan, and as far south as northern Australia.

habitat

Prefers the sheltered shallow waters of lagoons, where it takes up residence among sea anemones.

behavior

Most well known for its symbiotic relationship with the sea anemone. The clown anemonefish lives safely among the stinging cells, or nematocysts, of the anemone due at least in part to the specialized mucus layer that coats the fish. In this arrangement, the fish gains protection from predators, while the anemone receives a regular cleaning from the clown anemonefish. The fish has such a symbiotic relationship with four different species of sea anemones.

feeding ecology and diet

Eats mainly invertebrates that it often finds among the sea anemone's tentacles. Usually ventures only short distances from the shelter of the anemone, which has stinging tentacles. The sting deters most other species, making the anemone a safe haven.

reproductive biology

Protandrous, lives in small groups in which all but two fishes are sexually immature males. The largest two in each group are sexually mature, with the larger being the only female in the group. If the female is removed, the sexually mature male develops into a sexually mature female, and the next largest has a growth spurt and becomes the sexually mature male. A dominance hierarchy controls the shift from male to female, and from immature to sexually mature.

conservation status

Not listed by the IUCN.

significance to humans

Very popular marine aquarium fish. Many of the individuals sold are captive-bred.

Blue chromis

Chromis cyanea

family

Pomacentridae

taxonomy

Chromis cyanea Poey, 1860, Cuba.

other common names

Spanish: Cromis azul.

physical characteristics

Total length 6 in (15 cm). Shimmering, blue with black dorsal shading, strongly forked tail, and dark eyes. Tail and belly also have some black coloration.

distribution

Western Atlantic Ocean near Bermuda, also from northern South America to the West Indies and into the Gulf of Mexico.

habitat

Reef fish, prefers deeper waters up to 200 ft (61 m) deep with coral overhangs and crevices where it can take shelter when threatened.

behavior

Travels in sometimes multispecies schools, especially when feeding. Usually shy, will dash to the cover of reef when it feels threatened, and has been observed to dim its bright blue coloration to a duller gray.

feeding ecology and diet

Engages in group feeding of drifting zooplankton, but is territorial when feeding on algae and will defend an area against other algae-feeding species.

reproductive biology

Male may spawn with several females and guards all eggs in his nest until hatching, which takes up to one week.

conservation status

Not listed by the IUCN.

significance to humans

A popular commercial aquarium fish.

Garibaldi damselfish

Hypsypops rubicundus

family

Pomacentridae

taxonomy

Hypsypops rubicundus Girard, 1854, Monterey, California, United States.

other common names

English: Garibaldi; French: Chauffet Garibaldi; Spanish: Jaqueta vistosa.

physical characteristics

Standard length 11.8 in (30 cm). Deep bodied, small mouthed, almost uniformly orange.

distribution

Occurs in subtropical waters off the west coast of North America from Monterey Bay in central California south about 600 mi (966 km) to Guadalupe Island, Mexico.

habitat

Lives in rocky-bottomed, reef-associated waters up to 100 ft (30.5 m) deep among and near caves, crevices, and other cover.

behavior

Adults defend a home territory.

feeding ecology and diet

Feeds on vegetation and invertebrates, especially crustaceans, sponges, and worms.

reproductive biology

Spawns in a bed of red algae, which the male prepares and tends. Courtship includes male visual and tactile displays. The female lays the eggs, the male guards them.

conservation status

Not listed by the IUCN.

significance to humans

State marine fish of California.

Yellowtail damselfish

Microspathodon chrysurus

family

Pomacentridae

taxonomy

Microspathodon chrysurus Cuvier, 1830, St. Thomas Island.

other common names

English: Jewelfish (as juveniles); French: Chaffet queue jaune; Spanish: Jaqueta rabo amarillo.

physical characteristics

Length 8.3 in (21 cm). Juveniles typically dark blue with sky blue spots on all but the yellow tail. Adults are golden brown with dark-outlined scales and a yellow tail.

distribution

Western Atlantic Ocean near Bermuda, also from northern South America to the West Indies and southern Florida, United States, and into the southern Gulf of Mexico.

habitat

Shallow waters of shelter-filled coral reefs, usually associated with yellow stinging coral.

behavior

When food is abundant, shares feeding area with other wrasses, but will weakly defend a territory if food is limited. Juveniles sometimes engage in cleaner activities.

feeding ecology and diet

Prefers grazing on algae, but also takes invertebrates, especially coral polyps.

reproductive biology

Spawns mostly during semiannual periods. As males prepare nests, their coloration lightens. Female coloration brightens as they arrive to lay their eggs. Males tend and guard the eggs.

conservation status

Not listed by the IUCN.

significance to humans

Occasional food fish and aquarium fish.

Striped parrotfish

Scarus iseri

family

Scaridae

taxonomy

Scarus iseri Bloch, 1789, St. Croix Island, Virgin Islands, West Indies.

other common names

English: Gray chub, mottlefin parrotfish; French: Perroquet rayé; Spanish: Jabón, loro rayado.

physical characteristics

Total length 13.7 in (35 cm). Dark horizontal stripes are key feature of initial-phase individuals. Most prominent stripe is typically a center marking extending through the eye and nearly to the tail, where it narrows and fades. Juveniles are similarly patterned. Terminal-phase males are turquoise.

distribution

Lesser and Greater Antilles to southern Florida, United States, south along the South American coast to Brazil.

habitat

Prefers reef waters from the surface to 100 ft (30.5 m) deep.

behavior

Typically schools, sometimes defends feeding territories if resources are limited or fish population numbers are high. Conspecific territorial displays include fanning of the ventral fins, opening of the mouth, and noncontact rushes toward one another.

feeding ecology and diet

Forms schools for feeding on algae, which it scrapes from rocks and other surfaces.

reproductive biology

Initial-phase males and females may become terminal-phase males; female-to-male switch takes less than two weeks. Mating occurs year round, either in pairs or in groups. A broadcast spawner that gives no parental care to its pelagic eggs.

conservation status

Not listed by the IUCN.

significance to humans

Minor commercial and aquarium fish.

Stoplight parrotfish

Sparisoma viride

family

Scaridae

taxonomy

Sparisoma viride Bonnaterre, 1788, Bahamas.

other common names

English: Moontail, parrot chub, redbelly; French: Perroquet feu; Spanish: Loro viejo.

physical characteristics

Total length 25 in (64 cm). Females and younger adult males have mostly blue-gray body scales outlined in dark gray; reddish belly, tail, and fins. Colorful terminal-phase males mostly green, with blue and reddish horizontal stripes on head and lower ventral body, and yellow and blue markings on the tail, which is shaped like a crescent moon.

distribution

Western Atlantic from southern Florida, United States, to Brazil, also around Bermuda.

habitat

Juveniles prefer shallow sea grass beds and vegetated areas, adults inhabit coral reefs.

behavior

Diurnal; lives alone or in small groups; moves to the sea bottom at night. Has been known to accept cleaning services from other species.

feeding ecology and diet

Feeds mainly on algae and other plants, but will eat corals. Feeding occurs only during the day. Will become territorial of feeding areas if food is limited.

reproductive biology

Initial-phase individuals may be either male or female; terminal phase is male. Initial-phase females require three weeks to become terminal-phase males. Mating occurs year round.

conservation status

Not listed by the IUCN.

significance to humans

Minor commercial and aquarium fish.

Resources

Books

Allen, Gerald R. "Damselfishes." In Encyclopedia of Fishes, edited by John R. Paxton and William N. Eschmeyer. 2nd edition. San Diego: Academic Press, 1998.

Choat, J. Howard, and David R. Bellwood. "Wrasses and Parrotfishes." In Encyclopedia of Fishes, edited by John R. Paxton and William N. Eschmeyer. 2nd edition. San Diego: Academic Press, 1998.

Helfman, Gene S., Bruce B. Collette, and Douglas E. Facey. The Diversity of Fishes. Malden, MA: Blackwell Science, 1997.

Michael, Scott W. Reef Fishes: A Guide to Their Identification, Behavior and Captive Care. Volumes 1–3. Shelburne, VT: Microcosm Ltd., 1998.

Randall, John E., Gerald R. Allen, and Roger C. Steene. Fishes of the Great Barrier Reef and Coral Sea, 2nd edition. Honolulu: University of Hawaii Press, 1997.

Periodicals

Bshary, R., and D. Schäffer. "Choosy Reef Fish Select Cleaner Fish That Provide High-Quality Service." Animal Behaviour 63 (2002): 557–564.

Donaldson, T. J., and Y. Sadovy. "Threatened Fishes of the World: Cheilinus undulatus Rüppell, 1835 (Labridae)." Environmental Biology of Fishes 62 (2001): 428.

Francini-Filho, R. B., R. L. Moura, and I. Sazima. "Cleaning by the Wrasse Thalassoma noronhanum, with Two Records of Predation by its Grouper Client Cephalopholis fulva." Journal of Fish Biology 56, no. 4 (2000): 802–809.

Kavanagh, K. D. "Larval Brooding in the Marine Damselfish Acanthochromis polyacanthus (Pomacentridae) Is Correlated with Highly Divergent Morphology, Ontogeny and Life-History traits." Bulletin of Marine Science 66, no. 2 (2000): 321–337.

Organizations

IUCN/SSC Grouper and Wrasse Specialist Group. Department of Ecology and Biodiversity, The University of Hong Kong, Hong Kong, China. Phone: (852) 2859 8977. Fax: (852) 2517 6082. E-mail: [email protected] Web site: <http://www.hku.hk/ecology/GroupersWrasses/iucnsg/index.html>

Leslie Ann Mertz, PhD