Order Perciformes
Suborder Anabantoidei
Family Osphronemidae
Subfamily Macropodusinae
Genus Betta, or fighting fish — Betta.
Distribution of the genus Betta into groups.
Akarensis complex: Betta akarensis (Regan, 1910), Betta antoni (Tan & Ng, 2006), Betta aurigans (Tan & Ng, 2004), Betta balunga (Herre, 1940), Betta chini (Ng, 1993), Betta ibanorum (Tan & Ng, 2004), Betta obscura (Tan & Ng, 2005), Betta pinguis (Tan & Kottelat, 1998).
These are medium-length fighting fish with green or golden iridescence. Some species originate from acidic environments, while others live in more neutral waters. Water quality is essential for these species, and good filtration is required. For breeding, the water should be soft and neutral to acidic. An aquarium with dense vegetation and floating plants to tone down the lighting is recommended. They adapt quite easily to aquarium foods, however, live foods are necessary during spawning. Spawning sometimes occurs in mid-water levels, but usually in caves.
Albimarginata complex: Betta albimarginata (Kottelat & Ng, 1994), Betta channoides (Kottelat & Ng, 1994).
Males have brilliant coloration even outside of spawning, and during spawning, they bloom in bright colors. An aquarium with plenty of aquatic vegetation and flower pots for shelter is ideal. They can be kept in almost any aquatic environment, but best in soft and acidic water. Betta channoides requires iron in the water to maintain health. Dry artificial foods are not recommended; they must be fed live and frozen foods. Males incubate eggs in their mouths.
Anabatoides complex: Betta anabatoides (Bleeker, 1851).
Bellica complex: Betta bellica (Sauvage, 1884), Betta simorum (Tan & Ng, 1996).
These large fighting fish are rarely kept in aquariums. Males are typically larger and have torch-shaped caudal fins, while females have rounded bellies. Due to their large size, large aquariums are necessary. The nest is built from bubbles using floating plants. The water should be soft and neutral.
Coccina complex: Betta brownorum (Witte & Schmidt, 1992), Betta burdigala (Kottelat & Ng, 1994), Betta coccina (Vierke, 1979), Betta livida (Ng & Kottelat, 1992), Betta miniopinna (Tan, 1994), Betta persephone (Schaller, 1986), Betta rutilans (Witte & Kottelat, 1991), Betta tussyae (Schaller, 1985), Betta uberis (Tan & Ng, 2006).
The complex of red fighting fish. Species such as Betta brownorum, burdigala, coccina, livida, miniopinna, persephone, rutilans, and tussyae typically inhabit peat swamps where the pH ranges from 3.9 to 6.5. They require neutral to slightly soft water. An aquarium with many shelters and dense plant planting is needed, large-leaved Cryptocoryne species are desirable, and floating plants are mandatory. The vast majority easily adapt to dry foods, but some may require live and frozen foods. Many of these species are kept in pairs; males are territorial during the spawning period. Juveniles grow slowly, reaching adult size by one year.
Dimidiata complex: Betta dimidiata (Roberts, 1989), Betta krataios (Tan & Ng, 2006).
Edithae complex: Betta edithae (Vierke, 1984).
Foerschi complex: Betta foerschi (Vierke, 1979), Betta mandor (Tan & Ng, 2006), Betta rubra (Perugia, 189), Betta strohi (Schaller & Kottelat, 1989).
These fishes originate from blackwater bodies and require similar conditions in captivity. They prefer soft and acidic water.
Picta complex: Betta falx (Tan & Kottelat, 1998), Betta picta (Valenciennes, 1846), Betta simplex (Kottelat, 1994), Betta taeniata (Regan, 1910).
These are the most common among aquarists. These species adapt well to aquarium conditions, except for B. taeniata, which are prone to disease when water conditions are not met. The aquarium should have caves where the fish can retreat if necessary, and plants are also helpful. These species are quite tolerant of pH and hardness, but require clean water. They eat all aquarium foods, but derive pleasure from live and frozen products, which are also necessary for their spawning. Male courtship can last for several days. When the female is ready, she begins to nip the male’s caudal fin. The male incubates the eggs in his mouth. Females should be removed after spawning.
Pugnax complex: Betta breviobesus (Tan & Kottelat, 1998), Betta cracens (Tan & Ng, 2005), Betta enisae (Kottelat, 1995), Betta fusca (Regan, 1910), Betta lehi (Tan & Ng, 2005), Betta pallida (Schindler & Schmidt, 2004), Betta prima (Kottelat, 1994), Betta pugnax (Cantor, 1849), Betta pulchra (Tan & Tan, 1996), Betta raja (Tan & Ng, 2005), Betta schalleri (Kottelat & Ng, 1994), Betta stigmosa (Tan & Ng, 2005).
They are also frequently kept in aquariums, with some species reaching 5 cm in length. These species usually have a brown coloration with green or golden iridescence. Males have elongated caudal, anal, and ventral fins. Females are aggressive; in some species, unresponsive males may be killed during spawning preparation, and females are quite territorial, chasing away intruders up to the point of killing them. Usually, parents do not touch the fry, but an aquarium with dense vegetation and plenty of hiding places is needed. Juveniles grow slowly, reaching adult size by one year.
Splendens complex: Betta imbellis (Ladiges, 1975), Betta mahachai (Panitvong, Nonn, 2002), Betta smaragdina (Ladiges, 1972), Betta splendens (Regan, 1910), Betta stiktos (Tan & Ng, 2005).
All these species prefer slightly soft, slightly acidic water. An aquarium with plenty of plants and hiding places is ideal. Plants can be live or artificial, as it does not matter to the fish. Some specimens may hide in shelters at first and come out only for feeding. Most prefer live food and eventually adapt to artificial foods. A pair is selected for spawning, which builds a bubble nest.
Unimaculata complex: Betta compuncta (Tan & Ng, 2006), Betta gladiator (Tan & Ng, 2005), Betta ideii (Tan & Ng, 2006), Betta macrostoma (Regan, 1910), Betta ocellata (de Beaufort, 1933), Betta pallifina (Tan & Ng, 2005), Betta patoti (Weber & de Beaufort, 1922), Betta unimaculata (Popta, 1905).
These are large, slender fighting fish with a very pronounced ability to jump out of the aquarium. They inhabit fast-flowing waters. They adapt well to aquarium conditions. Betta macrostoma is very sensitive to water conditions during acclimatization. The water must be very clean with good filtration. They can be very aggressive. Betta gladiator will not tolerate any other fish in its territory. It is essential to keep them only in pairs rather than groups. It has been noted that females protect the males and the territory during and after spawning. There should be a sufficient number of caves in the aquarium for the fish to feel secure. Fry reach maturity between 6 months and 1 year of age.
Waseri complex: Betta chloropharynx (Kottelat & Ng, 1994), Betta hipposideros (Ng & Kottelat, 1994), Betta pi (Tan, 1998), Betta renata (Tan, 1998), Betta spilotogena (Ng & Kottelat, 1994), Betta tomi (Ng & Kottelat, 1994), Betta waseri (Krummenacher, 1986).
This is a complex of large yellow fighting fish. All species in this group lack iridescent colors on their gill plates. These species require a large aquarium and dense vegetation. They are quite tolerant of each other and rarely show aggression, making group keeping possible. Many of these species originate from locations where the water pH is below 5.5. Most species adapt well to tap water; however, soft water and sometimes a lower pH are required for spawning. Parents do not eat their fry.
Betta antoni, albimarginata, bellica.
Genus Betta, or fighting fish — Betta. 
