'Cichlasoma' cf. salvini
In the Rio Tacotalpa drainage of upper Rio Grijalva system, a cichlid reminding at 'C.' salvini can be found. Compared to 'C.' salvini from lower Grijalva and the Usumacinta system, this form has a much duller, brownish ground coloration and many individuals appear very high bodied (see also Stawikowski & Werner, 1998). It is unclear if this form is a distinct species or a geographical (or ecological) variant of 'C.' salvini.
Most interestingly, 'C.' cf. salvini inhabits a sulfurous creek near the village of Tapijulapa (Tabasco, México) (see: Extremophile cichlids).