Lately there has been a lot of discussion about the generic assignment of a group of Central American cichlids all more or less closely related to the species originally described as Cichlasoma maculicauda REGAN 1905 and Cichlasoma synspilum HUBBS 1935 . In order to decide to which genus these ( and a few other ) species belong , we first have to look at the availability of the proposed generic names . With availability I mean : can the names safely be used for any cichlid genus without breaking the rules of the International Commission on Zoological Nomenclature ( ICZN ). Vieja was described by Fernandez-Yepez in 1969 . This Venezuelan author designated Cichlasoma milleri ( a species also newly described by him ) to be the type species for his new genus , as the rules of the ICZN require . Later it turned out that Cichlasoma milleri was a synonym of Cichlasoma maculicauda , rendering the latter as the name of the type species of Vieja . The meaning of this is that whenever Cichlasoma maculicauda were to be placed in a separate genus of its own , the name of that genus would have to be Vieja . Keeping it in Cichlasoma on the other hand would make the name Vieja a synonym of Cichlasoma , because the name Cichlasoma is of an older date ( the priority rule ). The story for Paratheraps is roughly the same . Proposed by Werner & Stawikowski in 1989 ( after their first description in 1987 failed to assign a type species ) it has Paratheraps breidohri as its type species . Both names are thus available and may be used as generic names for ( cichlid ) species . Next question to be addressed is whether these two names are valid . As I said above , if maculicauda would have been kept in Cichlasoma , the name Vieja would become synonym . And synonyms are not valid . They cannot be used as valid names for cichlid taxa . Since Kullander ( 1983 ) restricted the name Cichlasoma to 12 species of cichlid fish from South America , it seems illogical to assign the two Central American species at hand to this genus . The species maculicauda and breidohri will most likely never again belong to Cichlasoma for this reason . Lacking another available generic name for these species ( older than the ones proposed by Fernandez- Yepez and Werner & Stawikowski ) it follows that both species may safely be assigned to these two genera . The generic names Vieja and Paratheraps are thus also valid , their type species being Vieja maculicauda and Paratheraps breidohri respectively . Unless of course it would be shown that both species actually belong to one genus . In that case the younger of the two names ( Paratheraps ) would become a synonym of the older ( Vieja ). The discussion would end . All species concerned would have to be called Vieja . Some authors ( mainly aquarists ) are of this opinion . The problem is that these authors rarely give supportive arguments / evidence for their opinion . But this complicated matter may be solved in the near future . Recently some very interesting papers have been published on the phylogeny ( interrelationships ) of Central American cichlids . Oldřich Říčan and co-workers ( 2008 ) studied most of the Central American heroine cichlids ( including Paratheraps and Vieja ) using both DNA and morphology . Molecular ( DNA ) and morphological characters are good indicators of relationships . Generic
22