The slender lungfish is a freshwater fish and it largely inhabits the middle and lower Congo River basin.[3] It is a primarily demersal fish, dwelling in the riverbeds of the above basins and in Stanley Pool.[3][1] During spawning season, females can be found in open water.[3][1]
Biology
The slender lungfish has an anguilliform body, much like an eel.[3] The body of the slender lungfish is generally brown; young of the species oftentimes have black spots throughout the body, however adults generally lose these spots as they age.[3] Like all African lungfish the slender lungfish is an obligate air-breather and is capable of aestivation; however, it generally does not aestivate.[3] When it does aestivate, the lungfish creates a dry mucus cocoon on land.[4] As most tropical fish are ammoniotelic, being on land can induce ammonia toxicity – with negative organismal and cellular level consequences – due to a lack of water to flush excreted ammonia from the gills and other cutaneous surfaces.[4] Studies have shown that the slender lungfish has evolved the ability to reduce endogenous ammonia production, as well as an ornithine-urea cycle to increase the conversion rate of ammonia to less toxic urea, to defend against this toxicity.[4][5]
Reproduction
Spotted lungfish nests are generally found in June through October.[1] During this time period the male makes a nest and buries it in mud, not unlike the marbled lungfish mating behavior.[1] He guards both eggs and larvae during this time.[3][1] The female does not take care of the young but rather during this time can be found open water in rivers within its range.[3]
Fishman, A. P., Pack, A. I., Delaney, R. G. and Gallante, R. J. (1987). Estivation in Protopterus. In The Biology and Evolution of Lungfishes(ed.) W. E. Bemis, W. W. Burggren and N. E. Kemp), pp. 163–179. New York: Alan R. Liss, Inc.