The cichlid genus Vieja is no longer valid, according to a study to be published in a forthcoming issue of the journal Molecular Phylogenetics and Evolution.
Caleb McMahan, Aaron Geheber and Kyle Piller constructed a molecular phylogeny of 90 species of cichlids. The analysis included all 16 species currently assigned to Vieja and all other species that had been assigned to Vieja at one time or another.
The authors found in their analyses that Vieja was not a monophyletic group, (ie. all species currently assigned to it did not share a most common recent ancestor (MRCA)).
Eleven species (V. fenestrata, V. guttulata, V. zonata, V. hartwegi, V. bifasciata, V. breidohri, V. argentea, V. regani, V. melanura, V. synspila, and V. maculicauda) were found to be most closely related to Paraneetroplus bulleri, and have been reassigned to the genus Paraneetroplus.
Another three species (V. intermedia, V. godmanni, and V. microphthalma) were found to be most closely related to Theraps, and have been reassigned to the latter genus.
The Pantano cichlid (Herichthys pearsei) was also recovered as a member of the Theraps clade and has also been reassigned to this genus.
The two remaining species (V. heterospila and V. tuyrensis) were recovered outside of the Paraneetroplus and Theraps clades, and have been provisionally reassigned to the genus 'Cichlasoma' (which is widely considered to be eventually divided into several genera, hence the quotation marks).
For more information, see the paper: McMahan, CD, AD Geheber and KR Piller (2010) Molecular systematics of the enigmatic Middle American genus Vieja (Teleostei: Cichlidae). Molecular Phylogenetics and Evolution doi:10.1016/j.ympev.2010.09.005