chapter
1
Over
160 genera and more than 1300 species make up the Family
Cichlidae (sick-LID-ee). Fish
belonging to this Family are collectively known as Cichlids
(sick-lids). The word
Cichlidae is derived from the Greek word kikhle
meaning a kind of sea fish.
Cichlids
belong to the Order Perciformes (purse-EE-forms),
which also contains the Families Belontiidae
(bell-on-tee-EE-dee), which includes Labyrinth Fish such
as Siamese Fighting Fish; Toxotidae (Archerfish)
and Gobiidae (Gobies), as well as
marine fish Families.
Cichlids
are highly evolved freshwater fish whose origins are in marine
fish such as damselfish and wrasses. These ancient links with
the sea allow cichlids to live in a wide range of water
conditions, from soft acidic water to nearly marine conditions.
The family Cichlidae
has ancestors so old that they evolved before Africa and America
drifted apart. They first evolved before the super-continent break-up
more than 150 million years ago and probably split into the major
lineages 70-95 million years ago.
Cichlid
features.... 
It is often not possible to determine
from appearance alone whether a fish is a cichlid or not.
With some it is obvious, but others look like cichlids
when in fact they belong to a totally different and unrelated
Family.
Fish
placed by ichthyologists (scientists who study fish) are there
because of their evolutionary history. In appearance, cichlids
are quite diverse in size, colour and body shape. Generally, cichlids
are perch-like fish, although some such as Discus and Angelfish
are not really typically perch-like. However, all cichlids
do have a number of unique anatomical features,
which differentiate them from other fish types.
Some of the features
universal to cichlids include:
- pharyngeal
(throat) teeth that assist in processing food;
- one
pair of nostrils;
- a single
dorsal fin with a number of hard fin rays at the front; and
- at least
three hard fin rays in the anal fin
Where
are cichlids found?
The natural distribution of cichlids ranges from:
- southern
Texas (North America) through Central America to Argentina (South
America)
- throughout
Africa and the Middle East into Egypt
- the islands
of Madagascar and Sri Lanka and along the southern coast of
India.
There are
no cichlids native to Australia or the Far East, nor are
they found naturally in North America north of Texas.
There are approximately 700 species found in Africa (including
Madgascar) and more than 200 in the Americas. There is only one
genus found in Asia, this being Etroplus with three species.
Most cichlids kept in captivity come from the Great African
Rift Lakes, Lake Malawi or Lake Tanganyika; various African rivers,
the Amazon Basin in South America and from Central America.
Cichlids are found in almost every type of freshwater within
their geographic range, including rivers and lakes, swamps and
even ditches and puddles, from extremely soft and acid to hard
and alkaline. Some cichlids also live in brackish waters.
They are not found at high elevations, but because there are so
many cichlids they can be found in cool waters (around
18oC) up to tropical temperatures over 30oC.
Breeding....
Cichlids have highly developed brood care and reproductive
behaviour. Cichlids fall into two broad breeding categories
Open and Shelter spawners.
- Open
spawners....
- lay
their eggs on an open surface, such as rocks, sand, and
plant leaves. Some open spawners will lay on a vertical
or sloped surface (see right - Discus with eggs), while
others lay on a flat, horizontal surface.
- generally
lay a large number of eggs at a time and they are usually
small and adhesive. There is no clear sexual dimorphism
between males and females.
- Open
spawners include Angelfish
(Pterophyllum),
Discus
(Symphysodon),
Severum
(Heros),
Vieja, Polleni
(Paratilapia) and Parachromis.
- Open spawners
are generally larger fish that rely on their size to intimidate
potential predators.
- Shelter spawners....
- can
be divided up into two general groups- Cave brooders
and Mouth brooders.
- Generally,
shelter spawners lay considerably less eggs than open spawners,
and have larger more colourful eggs. Males are generally
larger and more colourful than the female.
- Cave
brooders....
- lay
their eggs in caves or under overhanging rock or driftwood.
Both parents participate in brood care and can become
aggressive towards other fish while caring for the eggs
and the fry.
- Cave
brooders include Apistogramma, Julidochromis,
Nannacara, Neolamprologus, Pelvicachromis
and Steatocranus.
- Many
cavity brooders are also classified as Dwarf Cichlids.
- Because
they don't generally have size on their side when defending
their eggs, they rely on hiding their spawn.
- Mouth-brooders....
- are
fish that, at some point during brood care, take their
eggs or the larvae into their mouths.
- Mouth
brooders have a modified throat pouch that expands to
allow the eggs to be carried in safety.
- Mouth-brooders
are divided up into two further categories depending on
when the parents take the eggs/fry into the mouth.
- Ovophile
or immediate mouth-brooders
-
- The
male often makes a pit in his territory, where the
eggs are laid.
- The
female picks the eggs up during spawning.
- After
hatching the fry remain in the safety of the mother's
mouth until they can fend for themselves.
- In
some species, the male often has colourful, oval-shaped
marks on his anal fin called dummy
egg spots.
- These
spots play an important part in the fertilisation
of the eggs.
- After
the female has laid her eggs and takes them into her
mouth she sees the eggs spots on the male's anal fin
and thinks they are eggs she missed.
- She
will try to pick them up and when she does this the
male releases sperm which the female takes into her
mouth, causing the eggs to be fertilised (right -
male Lethrinops oculatus with many egg spots
on anal fin).
- While
the female is brooding she will not eat and will often
remain apart form other fish. Mouth brooders offer
protection to the fry even after they are free swimming.
- When
danger threatens, the fry will swim into the safety
of their mother's mouth. Ovophile mouthbrooders include
Aulonocara, Dimidiochromis, Fossorochromis,
Labidochromis, Metriaclima and Pseudotropheus.
- Larvophile
or delayed mouth-brooders
lay their eggs on the substrate.
- The
eggs are guarded where they are laid and after they
hatch, the female picks up the fry and keeps them
in her mouth.
- Sometimes
the parental protection stops after the fry are released
from the mouth.
- Larvophile
mouth-brooders include Gymnogeophagus and Satanoperca
(Satanoperca leucosticta
- right).
- Some
larvophile mouth brooders are biparental, meaning
that both the male and female take turns in brooding
the fry.
- Cichlids
are generally:
- Monogamous
- forming pair bonds, which may be strong or weak depending
on the genus (some genera, such as Julidochromis,
form unstable pair bonds that are easily broken if the fish
are stressed) or
- Polygamous
- forming harems where one male will often spawn with several
females.
Brood care....
Cichlids take care of their young in several different
ways. There are several common brood care patterns among cichlids.
- Nuclear
Family....
- Both
parents equally share the duties of caring for the young.
- Nuclear
families are usually formed by monogamous, open spawners
such as Discus, Angelfish, although
there are exceptions.
- Matriarch/Patriarch
Family....
- The
female guards the eggs and fry while the male defends the
territory.
- When
the fry become free-swimming, the parents raise the fry
equally.
- This
family form is also usually associated with monogamous,
open spawners (see right - Vieja synspillum female
with fry).
- Polygamous
or Harem Family....
- The
male defends a large territory, which includes multiple
spawning sites of several females.
- Each
female has responsibility for her own eggs and fry.
- Clear
sexual dimorphism is common.
- This
form of brood care is common among cave spawners such as
Apistogramma.
- Extended
Family....
- Both parents
as well as the offspring of previous spawnings care for the
young.
- Extended
Families are predominantly found in the cave spawners of Lake
Tanganyika, such as fish belonging to the genera Julidochromis
and Neolamprologus.
- Some species
of Central American open spawners take the "extended family"
one step further and have been known to share a special symbiotic
relationship with other cichlids of a different genus entirely
(see Hypsophora nicaraguense Fact Sheet).
The popularity of
cichlids among aquarists probably comes from three things:
- many are easy
to keep;
- there are many
varieties to choose from and
- they exhibit
many interesting and unusual behaviours. Many
cichlids will interact with their owners and become bored
if they don't have activities in the tank to kepe them amused.
For instance, Red Devils have been known to wilfully destroy
their tank furnishings and equipment if they are not kept active
(a Ping Pong ball can provide endless amusement for the fish).
With few exceptions
cichlids can be kept and bred in aquaria. Hundreds of species
are currently available to the hobby in Queensland and many can
be kept with a minimum of equipment in tanks ranging from 40 litres
to as large as there is room for.
Some cichlids
require specialised care and are not for the beginner, but many
others are easy to keep and breed. More information about the
requirements of the individual genera and species can be found
in our WetPetz
Fish Fact Sheets.
Next
.... chapter 2
- Cichlid Behaviour in the Aquarium
