Theraps is a small fish genus from the cichlidae family. They are endemic to Central America, ranging from Mexico to Panama. Several Theraps sp. have been found across the southern United States as invasive species

Invasive species

"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....

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Several of the genera that were formerly included in "Cichlasoma", including "Theraps" are under further scientific review, including dna studies. A reclassification is expected in the next few years. The species listed below were the latest designations as of fall 2009. Distinctions between Vieja

Vieja

Vieja is a genus of fish from the family Cichlidae. The geographic distribution of the genus is limited to Central America, primarily Mexico, Guatemala and Nicaragua. In general Vieja are high bodied cichlids which grow to between 15-35 cm . There are 16 species of Vieja currently described...

 and "Theraps" are not fully clear at this time.

Theraps species are very territorial and aggressive towards others, especially during breeding. They may be kept in the same aquarium

Aquarium

An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...

 with other robust cichlids and catfish

Catfish

Catfishes are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the heaviest and longest, the Mekong giant catfish from Southeast Asia and the second longest, the wels catfish of Eurasia, to detritivores...

 with varying success. For breeding or maintaining multiple specimens, a tank of 40 gallons (151.4 l) or larger is recommended. Depending on fish size, a single specimen may be kept in a tank of 20 to 40 US gal (75.7 to 151.4 L).

Omnivorous feeders, they eat a wide variety of insects, crustaceans, small fish, worms, algae, and plant material. As with many other cichlids, they may dig out or chew up aquarium plants. In aquaria prepared flake and pellet foods as well as frozen or live invertebrates will be readily consumed. Theraps sp. should also be offered a variety of steamed or boiled vegetables, such as peas, spinach, zucchini, lima beans, or brussels sprouts.

Theraps lay several hundred eggs on flat stones, or in a pit in the sand or gravel. Mature adults are very attentive parents and may injure or kill other fish when guarding the young (fry). Males are often more colorful and generally larger than females, and may develop a hump on the head as they age. Captive breeding is difficult to very difficult; live foods, frequent water changes, and a temperature increase of 2 to 4 degrees encourages spawning. Several artificial or rock caves for fish to hide from each other are advisable.

Species

"Cichlasoma" (Theraps) bifasciatum

• size up to 10" (25 cm)
• native to Mexico , Guatemala
• also known as (AKA): Red-spotted Cichlid, Cichlasoma melanurum , Astronotus bifasciatum, Cichlasoma bifasciatus
• water conditions: pH 6.5-7.5 , dH 2-15 (6), 72-82°F (22-28°C)

"Cichlasoma" (Theraps) maculicauda

• size up to 12" (30 cm)
• southern Mexico to Panama
• AKA: Black Belt Cichlid, Astatheros maculicauda, Astronotus parma, Chuco globosum, C. manana, Cichlasoma globosum, C. manana, C. nigritum, C. parma, Heros parma
• water conditions: pH 6.5-8 , 4-15 dH (6), 72-82°F (22-28°C)

"Cichlasoma" (Theraps) nicaraguensis

• size to 10" (25 cm)
• Nicaragua , Costa Rica
• AKA: Nicaragua Cichlid, Nicaraguense, Spilotum, Cichlasoma balteatum, C. nicaraguense, C. spilotum, Heros nicaraguensis
• water conditions pH 6.7-8 , 4-20 dH (10), 73-81°F (23-27°C)

"Cichlasoma" (Theraps) wesseli

• AKA: Wessel's Cichlid
• up to 20cm (8in)
• northern Honduras
• water conditions pH 7.4 - 8.2 ,73-81°F (23-27°C)

"Cichlasoma" (Theraps) coeruleus

• size to 6in (15cm)
• native to Usumacinta river, Mexico and Guatemala; also found as an invasive species
  Invasive species
  "Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
  
   in the Trinity River (Texas)
  Trinity River (Texas)
  The Trinity River is a long river that flows entirely within the U.S. state of Texas. It rises in extreme north Texas, a few miles south of the Red River. The headwaters are separated by the high bluffs on the south side of the Red River....
  
  . (Personal observation of Keith Jennings, an experienced aquarist near Dallas, TX.)
• ph 7.0 to 8.0 dh 9 to 20, 22-28°C
• prefers robust water movement (rheophilic), feeds mainly on algae and invertebrates

"Cichlasoma" (Theraps) irregularis information needed

"Cichlasoma" (Theraps) lentiginosus information needed