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Labroidei
Omar Sinno
Michelle Harris
Labroidei
Class: Actinopterygii
Order: Perciformes
Suborder: Labroidei
4 Families within Suborder
Labroidei
• Cichlidae
•Embiotocidae
•Pomacentridae
•Labridae
•Includes the scarid and
odacids, although many
argue that they are separate
families
Labroidei
 Suborder includes extremely speciose and
widely inhabited species.
 Tropical and Temperate marines species
 Reefs, kelp beds, surf zones and tide pools
 Tropical with few temperate freshwater
species
 Lakes, sluggish rivers and fast streams
 Few species found in brackish water
Pharyngeal Jaw : Uniting
the Labroidei
 Fused fifth ceratobranchials with teeth
 Muscle “sling” suspending the lower pharyngeal jaw
from the skull
 Articulation between the upper pharyngeal jaws and
the base of the skull without intervening muscle
 Undivided sheet of sphincter esophagi muscle
 Diversification of jaw structures integral to diet choice
and speciation of cichlids.
Family Cichlidae
 Generally tropical freshwater, however few
found in brackish waters.
 Nearly all species endemic to African rift Lakes.
 Other endemic species found in North America,
South America and the Middle East.
 However, introductions have made them
worldwide.
Family Cichlidae
 Non-continuous lateral line and single nostril
on each side.
 Average 12-15 inches in length but some
species up to a meter long.
 Several different body shapes:
Disc
Tubular
Stream-lined
Family Cichlidae
 Diversification of mouth, jaw and teeth allow cichlids
to eat a wide variety of food.
 Mollusks, algae, insects, zooplankton, other fish,
detris, plants and scales.
 Predation styles include both ambush and openpursuit.
 Caprichromis rams head of mouth-brooding
females, making her spit out eggs. Caprichromis
then eats the fry.
 Nimbochrmois and Parachromis play dead to lure
in small fish.
Family Cichlidae
 Very Territorial- Levels of territoriality is diverse
 Feeding (one of few f.w. spp) or Mating territoriality
 Can communicate
 Visual- color change may signify aggression,
dominance, individuality
 Tactile- “mouth fighting”
 Chemical- distinguishing fry
 Acoustic
http://www.youtube.com/watch?v=j7Rc8xP03B4
Family Cichlidae
 Invasive Cichlids
 Cichlids have been introduced by aquaria trade
 1300 aquarium species!
 California – Rio Grande Cichlid
 Hawaii – Jewel Cichlid
 Florida – Mayan Cichlid
 Australia – Pearl Cichlid
 Game Fishing
 Peacock Bass
 Biocontrol
 Food
 Egypt: Delicious Tilapia
 Uganda: Nile Perch
Cichlidae: Breeding
 Methods of mating diverse as well
 Monogamy
 Courtship rituals and parental care common
 Polygynous
 Male or female territoriality
 Polygynandrous
 “Lekking” (“To play” in Swedish)
 Congregation of 5,000-50,000 males
 Males build nests inshore or in open waters
 Females come to lay eggs in nests
 Extended Family model
 Colonization of related individuals with dominant male
Cichlinds displaying
Lekking
Family Cichlidae
 Two models of Reproduction
 Mouth-Brooding
 Most polygynous, monogamous and sexually
dimorphic
 Females and Males may mouth-brood
 Substrate-Brooding
 Fertilized eggs adhered to substrate and guarded
by parents until hatched.
 Parents tend to be monogamous or sexually
monomorphic.
Sensory Systems and
Speciation
 Cichlid coloration and vision supports that
geographic isolation not necessary for
speciation in Cichlids.
 Mutations and adaptations in vision allows
different cichlid species to inhabit different
levels in the water column.
 Fish have adapted to best respond to certain
colors that correspond to differences in color in
varying depths.
Conservation of Cichlidae
 43 species extinct
 Small habitats in endemic locations make
native species vulnerable to extinctions
 Introduction of Nile Perch to Lake Victoria
as food source has decimated cichlid
populations.
Cichlids-Speciation
 There are a number of hypotheses as to why
the cichlids are so diverse
 Lake Victoria flowed over into smaller surrounding
lakes allowing the cichlids to inhabit the smaller
lakes. When the water recedes, the fish in the
smaller lakes are isolated from the rest of the
population leading to speciation. When Lake
Victoria floods again, some of the fish swim back
from the small lake into Lake Victoria.
 Other hypotheses theorize that sympatric processes
within the lake caused divergence
Cichlids-Speciation
 So there is a large number of species, but how
fast did they diverge?
 There are 900 species in African rift lakes. 12,400
years ago, Lake Victoria was a marsh. This would
indicate an extremely fast pace for speciation
 However, molecular clock data calculated using an
assumed 5.6 percent divergence in DNA sequence
every million years came up with the conclusion that
Lake Victoria cichlids began evolving 100,000 to
200,000 years ago. This indicates that cichlids
diverged after the break up of Gondwanaland.
 This is supported by the number of cichlids in South
America. They migrated between Africa & South
America when the two were connected as
Gondwanaland.
Cichlid Sympatric
Speciation
Embiotocidae
 Surfperches
 Inhabit marine waters, typically kelp
beds, rocky reefs, and tidal zones
 Some species eat zooplankton, while
others eat invertebrates
 The only family of vivparous in Labroidei
Pomacentridae
 Includes damselfish and clownfish
Damselfish
 Resides in tropical marine waters, typically in
shallow areas close to coral reefs
 Highly territorial
 Guard a small patch of algae in a symbiotic
relationship
 The damselfish tend their algae like a garden
 They strategically feed on certain areas so as not to
deplete the algae
 Viciously attack any fish trying to steal a bite
 Males court females from their patch.
 If successful, they also guard the eggs
Clownfish
 http://www.youtube.com/watch?v=bZ1KDf3OqU
 Live in anemones in tropical marine waters
 Why don’t the anemones sting the clownfish
and inject them with neurotoxins?
 The clownfish have a sugar based mucous rather
than protein so the anemone does not recognize it
as food
 Their coevolution has led to the clownfish’s
immunity to the neurotoxin
Clownfish
 Again this is a symbiotic relationship
 The anemone protects the clownfish from predators
 The clownfish eats matter off the anemone that
could potentially be harmful
 The clownfish also provide nutrients for the
anemone through their fecal matter
 Clownfish are monogamous in the Christian
sense, til death do they part
 Clownfish groups are typically comprised of a
breeding pair and some pre-pubescent males
 When the female dies, the dominant male becomes
the female (protandrous hermaphrodites)
Labridae
 The wrasses
 Includes at least 500 species
 Inhabit shallow, tropical marine waters,
typically close to coral reefs but can range to
colder waters
 Wrasses are colorful and sexually dimorphic
 Originally born as a mix of females and males
 The dominant males and females become the
breeding males (protogynous hermaphrodites)
 The submissive males become female mimics, but
do not become females
 The submissive females remain females
Labridae
 Some species also participate in a symbiotic
relationship: the famed cleaner fish
 Other fish swim to a group of wrasses and usually
give a signal: open their mouth or orient themselves
vertically
 The wrasses come and clean the parasites off of the
fish
 The wrasses even make house calls to shy fish
 Occasionally there are cheater wrasses who eat
protective mucous or healthy tissue
 The “clientele” fish rarely eat the wrasses due to the
enormous benefit of being cleaned of all of their
potentially deadly parasites
Odacidae
 This family includes a mere 12 species
 Their habitat is the coastal waters off
Australia and New Zealand
 Body is long and slender like the wrasse
 Teeth are fused together like in the
parrotfish
Scaridae
 Parrotfish
 Inhabit shallow, tropical marine waters,
typically around coral reefs
 Typically one male has a harem of
females
 When the male dies, the dominant female
becomes the male (again, protogynous
hermaphrodites)
 Produce pelagic eggs (buoyant eggs, if you
forgot)
Scaridae
 http://www.arkive.org/humpheadparrotfish/bolbometopon-muricatum/video-08.html
 So aptly named because of their fused to teeth
which look like a bird’s beak
 They feed on algal fronds and pieces of dead coral
 How do they eat coral, you ask
 Massive pharyngeal teeth that grinds up the dead
coral
 They eat algal particles and live coral polyps
 Fun Fact! The sand that you laid on while you
tanned in the Caribbean is parrotfish fecal matter
Conservation
 The main source of endangerment for
these species is the depletion of the coral
reefs
 There are many factors
 Global warming
 Coral bleaching
 Coral acidification due to high CO2
 Coral disease
 Coral mining
 Pollution
Review questions
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What is the main hypothesis for Cichlid speciation and what is the
reasoning behind the accepted molecular clock?
What are the benefits that clownfish and anemone receive from their
symbiotic relationship?
Which families are protogynous hermaphrodites and which are
protandrous hermaphrodites
Think, what are some specific advantages to the damselfish gardening
algae?
What is “Lekking”?
Why has the Nile Perch been introduced to the Lake Victoria region and
what effect does it have to native cichlid species?
What are the advantages and disadvantages to the two types of brooding.
What types of water bodies would you think tubular, disc and stream-lined
cichlids inhabit?