All these are from the tribe within cichlids, called geophagini, there are 9 genera within the tribe, Gymnogeophagus is just one of those.Gymnogeophagus Mini earth eaters? Gymno - dwarf, geo-earth, phagus - eater. Are they true earth eaters?
Here are a few from thet eartheating geophagini tribe Gymnogeophagus.



Gymnogeopagus sp Paso Pache let, balzani middle, and the species from Arrojo Yebaliti right, all males.
A female Yerbalito below, with fry,



although not the tribe geophagini, there are earth eating cichlids from all over the globe
Thorichthys, Cribroheros, and Darienheros from Central America




Ptychochromis from Madagascar


There are even sand sifting cichlids like Fossorochromis, from the rift lakes of Africa.
Interesting how convergiant evolution makes them appear so similar.




