The redhump eartheater (''Geophagus steindachneri'') is a species of

eartheater Geophagini is a tribe of cichlids from the subfamily Cichlinae, the American cichlids. It is the sister taxon to the clade which includes the Cichlasomatini and Heroini. Fishes in the Geophagini are distributed from Panama south to Argentina, it ...

cichlid Cichlids () are a large, diverse, and widespread family of percomorph fish in the family Cichlidae, order Cichliformes. At least 1,760 species have been scientifically described, making it one of the largest vertebrate families, with on ...

from freshwater habitats in northwestern

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

.
Geophagus steindachneri
'.

FishBase FishBase is a global species database of fish species (specifically finfish). It is the largest and most extensively accessed online database on adult finfish on the web.

. Agustin, L., Kullander, S., & Torres, A. (2001-2008).

Distribution

The redhump eartheater is native to river drainages in northern and western

Colombia Colombia, officially the Republic of Colombia, is a country primarily located in South America with Insular region of Colombia, insular regions in North America. The Colombian mainland is bordered by the Caribbean Sea to the north, Venezuel ...

( Magdalena, Cauca and Sinú basins), and northwestern

Venezuela Venezuela, officially the Bolivarian Republic of Venezuela, is a country on the northern coast of South America, consisting of a continental landmass and many Federal Dependencies of Venezuela, islands and islets in the Caribbean Sea. It com ...

(

El Limón River The El Limón River is a river in Zulia in northwestern Venezuela. It flows into the Caribbean Sea. Tributaries include the Socuy River and Guasare River. See also *List of rivers of Venezuela This is a list of rivers in Venezuela. By draina ...

). It lives in water that is slightly acidic to neutral (6.5 to 7.0 pH) and typically about . It is

stenohaline Stenohaline describes an organism, usually fish, that cannot tolerate a wide fluctuation in the salinity of water. Stenohaline is derived from the words: "''steno''" meaning narrow, and "''haline''" meaning salt. Many fresh water fish, such as g ...

, found only in mainland

freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mi ...

environments.

Etymology

The cichlid is named in honor of Austrian ichthyologist

Franz Steindachner Franz Steindachner (11 November 1834 in Vienna – 10 December 1919 in Vienna) was an Austrian zoologist, ichthyologist, and herpetologist. He published over 200 papers on fishes and over 50 papers on reptiles and amphibians. Steindachner des ...

(1834–1919).

Food

Wild redhump eartheaters take

substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached ** Substrate (aquatic environment), the earthy material that exi ...

material into their mouths and sift out inedible bits of sand or gravel, while consuming

detritus In biology, detritus ( or ) is organic matter made up of the decomposition, decomposing remains of organisms and plants, and also of feces. Detritus usually hosts communities of microorganisms that colonize and decomposition, decompose (Reminera ...

and small organisms.

Reproduction

Redhump eartheaters are immediate maternal

mouthbrooder Mouthbrooding, also known as oral incubation and buccal incubation, is the care given by some groups of animals to their offspring by holding them in the mouth of the parent for extended periods of time. Although mouthbrooding is performed by a va ...

s. These fish grow relatively quickly, and can be sexed as subadults.

Sexual dimorphism Sexual dimorphism is the condition where sexes of the same species exhibit different Morphology (biology), morphological characteristics, including characteristics not directly involved in reproduction. The condition occurs in most dioecy, di ...

is clear - males have a large, red nuptial hump on their heads and grow larger than the females. Mature males develop an iridescence on the scales on their sides and very large humps. Males will display to females by opening their mouths and flaring their gills. Nonreceptive females may be driven from the spawning area. Spawning takes place on a smooth rock or clean sand bed. The female lays one or two eggs, then the male fertilizes them. The female immediately takes the fertilized eggs into her mouth and proceeds to lay more eggs. This continues until spawning is completed. The female carries the eggs until they are free-swimming and have absorbed their yolk sacs, about 2–3 weeks. She eats little to no food during this period. Eventually, she releases them and allows them to search for food, taking them back into her mouth when she feels threatened. The brooding female often signals to her fry when danger is present, and shuts her fry out of her mouth when encouraging then to forage.

Distribution

Etymology

Food

Reproduction

References

Further reading