Cichlid
Cichlids are a diverse family of freshwater fish, encompassing over 1,500 species across 140 genera. Known for their adaptability, cichlids inhabit a range of environments, primarily in tropical and subtropical regions of Africa, Asia, and the Americas. These fish vary significantly in size, shape, and dietary habits, with some being herbivorous, carnivorous, or detritivorous. Cichlids are particularly noted for their complex social structures and parenting behaviors, including mouthbrooding, where parents protect their eggs and young in their mouths. The family is classified within the ray-finned fishes of the Actinopterygii class and is part of the larger order Perciformes, which comprises many perch-like species.
Cichlids are popular in the aquarium trade, valued for their vibrant colors and engaging behaviors, such as greeting their owners. Additionally, they play an important role in aquaculture, with tilapia being one of the most widely farmed fish globally due to its nutritional benefits and fast growth. The rich diversity and ecological significance of cichlids continue to attract the interest of scientists, providing a window into evolutionary biology and environmental research.
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Cichlid
Cichlids are a large group of freshwater fish that form an important family of fishes. Pronounced "sick-lid," this group includes more than 1,500 individual known species of fish across 140 genera. Cichlids are known for their ability to adapt to a broad range of habitats. Additionally, certain species are so similar to each other that differences can only be identified via genetic analysis. For these reasons, new forms of cichlids are regularly discovered and the total number of species in the family remains undetermined. Known members include such seemingly dissimilar specimens as angelfish, tilapia, and peacock bass.
Classification
Cichlids are a branch of the Actinopterygii class of fishes that are taxonomically classified as the ray-finned fishes. Members of this class are placed together due to the presence of fins that are supported by protruding, bony rays that enable them to swim, among other functions. Together with such saltwater cousins as the wrasses, perch, and snappers, and such freshwater fish as sunfish and bass, cichlids form an enormous category of fishes called the Perciformes. This category includes all fish with "perch-like" characteristics—that is, with spinal fins divided into front and back portions called dorsal and anal fins. The Perciformes comprise the largest order of bony fishes and form one of the biggest categories of vertebrates, or animals with spines. The cichlids form such a large group that scientists estimate cichlid species comprise as much as five percent of all known vertebrates.
Cichlids are differentiated from other members of the perch family by the anatomical composition of their teeth and mouths. Many cichlids have other common traits, including the presence of a nostril on either side of the head, specializations of the digestive system and inner ear, and interrupted lateral lines, or a system of sense organs that allow them to detect movement in the water.
The cichlids likely evolved into a distinct family during the period before the supercontinent known as Gondwana split into several continents roughly 160 million years ago. From these origins, they evolved rapidly, eventually filling a number of specialized ecological niches.
Characteristics
Cichlids are a widespread family of fish that are found in mostly freshwater environments, although the family also includes a type of tilapia that is found in brackish waters, where freshwater and saltwater bodies meet. Cichlids demonstrate a broad diversity among species as a result of their ability to adapt to many different environments.
Known for their complex social structures, the cichlids are also regarded as among the most attentive parents in the fish world. Cichlids will guard their eggs against predators, with some species caring for their offspring through mouthbrooding, a type of behavior where they house eggs and larvae in their mouths until the eggs and larvae are mature enough to survive on their own.
Cichlids are found in the tropical and subtropical regions of Africa, Asia, and South and Central America, though a small number of species are known to live as far north as the Rio Grande Valley of Texas. The greatest diversity of species exists in Africa, with the Rift Lakes region of East Africa housing between 800 and 2,100 species alone.
Cichlids also demonstrate a great variety of eating habits, which has further enabled them to evolve and live in different environments. Some species feed exclusively on algae, while others are highly carnivorous (meat eaters). Other types of cichlid are defined as detritivores, or organisms that consume organic waste such as decaying plants and fecal matter.
Cichlids vary dramatically in shape. They can also be a range of sizes from smaller than an inch to over three feet in length. For example, the three-foot speckled peacock bass (Cichla temensis) of the Amazon River Basin is a highly prized game fish among the native inhabitants of the region.
Uses
Cichlids are among the most common fishes found in hobbyist aquariums due to their vivid coloring and ability to tolerate a variety of environmental conditions. In aquariums, one of the most popular types of cichlid fish are freshwater angelfish. While angelfish are valued for their shape and fragile beauty, other cichlids are known for their territorial natures, high intelligence, and attractive patterning. In addition, most members of the cichlid family used in the aquarium trade are prized for complex behavioral traits. Among aquarists, some cichlids even develop the habits of greeting their owners during feeding times or begging for additional food.
Several types of cichlids are also important in aquaculture, or the cultivation of aquatic organisms for human use. For example, tilapia are a key species in aquaculture; in the twenty-first century, they have become the third-most farmed type of fish. Their fast growth rate, taste, sustainability, and high levels of protein have made them a healthy, low-cost food alternative, especially for developing countries.
In addition, due to their widespread distribution, ability to adapt to new environments, and varied social, physical, and behavioral differences, cichlids are a continuing source of interest and study among ichthyologists, evolutionary and behavioral biologists, and environmental researchers.
Bibliography
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Elieson, Marc. "How Cichlids Get Named." Cichlid-forum. Aquaworks Web Solutions, LLC. Web. 14 Jan. 2016. http://www.cichlid-forum.com/articles/naming‗cichlids.php
Froese, R., and D. Pauly, eds. "Family Cichlidae—Cichlids." FishBase.org. FishBase. Web. 14 Jan. 2016. http://www.fishbase.org/summary/FamilySummary.php?ID=349
Jonna, R. Jamil. "Cichlidae/ Cichlids." Animal Diversity Web. University of Michigan Museum of Zoology. Web. 14 Jan. 2016. http://animaldiversity.org/accounts/Cichlidae/
Keenleyside, Miles H.A., ed. Cichlid Fishes: Behaviour, Ecology, and Evolution. London: Chapman & Hall, 1991. Print. 14 Jan. 2016.
Leibel, Wayne. "Cichlid Fish Information." Fish Channel. I-5 Publishing. Web. 14 Jan. 2016. http://www.fishchannel.com/freshwater-aquariums/species-info/cichlid/why-keep-cichlids.aspx
"Types of Cichlids—Fish Guides for African, South American, and Dwarf Cichlids." Animal-World Pet and Animal Information. Animal-World. Web. 14 Jan. 2016. http://animal-world.com/encyclo/fresh/cichlid/cichlids.htm