Mastacembelus is a genus of many species of spiny eel fish from the family Mastacembelidae. They are native to Africa (c. 45 species) and Asia (c. 15 species).[4] Most are found in rivers and associated systems (even in rapids[5]), but there are also species in other freshwater habitats and a particularly rich radiation is found in the Lake Tanganyika basin with 15 species (14 endemic).[6][7] A few species can even occur in brackish water.[8]
Appearance
Several Mastacembelus armatus caught in the Tlawng river in India. This species is sometimes kept in aquariums, but also considered a good food fish and eaten in its native range[8]
The size and pattern varies greatly depending on the exact species of Mastacembelus. The smallest are M. latens and M. simba, which only reach a maximum total length of 7–8 cm (2.8–3.1 in).[4][5] At up to 1 m (3.3 ft), the largest of both the family and this genus is M. erythrotaenia.[4][9]M. erythrotaenia, often known as the fire eel, is blackish with an orange-red pattern, and it is a popular aquarium fish.[9] Otherwise species in this genus are typically brownish and often have a spotted, speckled or mottled pattern, either in another brown hue, grayish or yellowish. This pattern is reflected in the common name of another species sometimes kept in aquariums, the zig-zag eelM. armatus (alternatively called the tire track eel, a name otherwise used for M. favus). A few others also occasionally appear in the aquarium trade,[9] and some are considered good food fish and eaten locally.[8]M aviceps, M. brichardi, M. crassus and M. latens are found in dark, deep parts of the Congo River and sometimes shallower among rocks. These four species have reduced eyes and are all pinkish-white in color (non-pigmented), similar to cavefish.[5]
Taxonomy
In an evaluation of the Mastacembelidae in 2005, the genera Caecomastacembelus and Aethiomastacembelus (formerly used for the African species) were placed in synonymy with Mastacembelus.[2]
According to FishBase, there are currently 61 recognized species in this genus.[4] 4 additional species (marked with a star* in the list) are recognized by Catalog of Fishes.[11]
^ abcBrown; Britz; Bills; Rüber; Day (2011). "Pectoral fin loss in the Mastacembelidae: a new species from Lake Tanganyika". Journal of Zoology. 284 (4): 286–293. doi:10.1111/j.1469-7998.2011.00804.x.
