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WORLD ATLAS OF CORAL REEFS
Wrasses (Labridae)
It is difficult to generalize about this group, which is not
only one of the largest groups, but also the most diverse
in terms of appearance and lifestyle. All wrasses are
carnivorous, but their diet varies considerably. The
humphead or Napoleon wrasse Cheilinus undulatus is the
largest member of the family. Reaching 229 centimeters
and over 190 kilos, it feeds primarily on molluscs and
crustaceans. Many of the smaller members of the group feed
quite generally on benthic invertebrates including some
large and quite diverse genera such as Thalassoma and
Halichoeres. A number of species feed on zooplankton,
including the genera Ciirhilabrus and Paracheilimis . In the
Indo-Pacific the cleaner wrasses Labroides spp. feed on
diseased or damaged tissues or external parasites of other
fishes - they establish cleaner stations and solicit the
attention of other fish, or may be approached by particular
fish requiring their services. This role is of considerable
importance, and many would-be predators allow these
wrasses to perform this service and even to enter the mouth
and gill areas without attempting to eat them.
Parrotfish (Scaridae)
Closely related to the wrasses, parrotfish are morphologically all relatively similar: elongate robust fishes, with
a powerful beak formed from the fusion of their teeth. The
majority are extremely colorful, although these color
patterns are also observed to change dramatically over the
course of the fish's lifetime. They are a predominantly
herbivorous group, and feed by scraping or excavating
the rock surface, often ingesting significant amounts of
rock with the benthic algae they eat. A few of the larger
species also feed in part on live coral. The largest, the
bumphead parrotfish Bolhomelopon muricaltim. reach
120 centimeters, and have been estimated to remove
between 2.5 and 5 tons of reef rock per year, converting
it to sand and thus acting as a major erosive force on
some reefs.
Surgeonfish (Acanthuridae)
This group is named for the sharp spines carried towards
the base of the tail and used in defense. They are another
highly reef-associated group, with relatively compressed,
oval-shaped bodies. Of the 72 species described only six
are recorded in the Atlantic. The majority of surgeonfish
are algal grazers, but a number, including the unicornfish
Naso spp., feed on plankton.
In addition to these large and conspicuous groups
there are very many others. Some, such as the highly
diverse blennies and gobies, and also the moray eels,
soldierfish, cardinalfish and scorpionfish, include many
reef-associated species, but may be less conspicuous on
the reefs. Others are regular visitors, including the sharks
Above: A long-nosed butterflyfish Forcipiger flavissimus, its fine mouth parts enabling it to forage for invertebrate food in
the fine structure of the reef. Center: The Indian dascyllus Dascyllus carneus, a small damsel which gains shelter amidst
branching corals. Below: A queen parrotfish Scarus vetula resting at night in a mucus bubble. Note the powerful "beak".
WORLD ATLAS OF CORAL REEFS
Wrasses (Labridae)
It is difficult to generalize about this group, which is not
only one of the largest groups, but also the most diverse
in terms of appearance and lifestyle. All wrasses are
carnivorous, but their diet varies considerably. The
humphead or Napoleon wrasse Cheilinus undulatus is the
largest member of the family. Reaching 229 centimeters
and over 190 kilos, it feeds primarily on molluscs and
crustaceans. Many of the smaller members of the group feed
quite generally on benthic invertebrates including some
large and quite diverse genera such as Thalassoma and
Halichoeres. A number of species feed on zooplankton,
including the genera Ciirhilabrus and Paracheilimis . In the
Indo-Pacific the cleaner wrasses Labroides spp. feed on
diseased or damaged tissues or external parasites of other
fishes - they establish cleaner stations and solicit the
attention of other fish, or may be approached by particular
fish requiring their services. This role is of considerable
importance, and many would-be predators allow these
wrasses to perform this service and even to enter the mouth
and gill areas without attempting to eat them.
Parrotfish (Scaridae)
Closely related to the wrasses, parrotfish are morphologically all relatively similar: elongate robust fishes, with
a powerful beak formed from the fusion of their teeth. The
majority are extremely colorful, although these color
patterns are also observed to change dramatically over the
course of the fish's lifetime. They are a predominantly
herbivorous group, and feed by scraping or excavating
the rock surface, often ingesting significant amounts of
rock with the benthic algae they eat. A few of the larger
species also feed in part on live coral. The largest, the
bumphead parrotfish Bolhomelopon muricaltim. reach
120 centimeters, and have been estimated to remove
between 2.5 and 5 tons of reef rock per year, converting
it to sand and thus acting as a major erosive force on
some reefs.
Surgeonfish (Acanthuridae)
This group is named for the sharp spines carried towards
the base of the tail and used in defense. They are another
highly reef-associated group, with relatively compressed,
oval-shaped bodies. Of the 72 species described only six
are recorded in the Atlantic. The majority of surgeonfish
are algal grazers, but a number, including the unicornfish
Naso spp., feed on plankton.
In addition to these large and conspicuous groups
there are very many others. Some, such as the highly
diverse blennies and gobies, and also the moray eels,
soldierfish, cardinalfish and scorpionfish, include many
reef-associated species, but may be less conspicuous on
the reefs. Others are regular visitors, including the sharks
Above: A long-nosed butterflyfish Forcipiger flavissimus, its fine mouth parts enabling it to forage for invertebrate food in
the fine structure of the reef. Center: The Indian dascyllus Dascyllus carneus, a small damsel which gains shelter amidst
branching corals. Below: A queen parrotfish Scarus vetula resting at night in a mucus bubble. Note the powerful "beak".