A redescription of the south American Cichlid FishPapiliochromis ramirezi(Myers & Harry, 1948) (Teleostei: Cichlidae)

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Abstract
Papiliochromis ramirezi (Myers & Harry in Anon., 1948), is a small cichlid restricted in distribution to the Llanos of Venezuela and Colombia. Its length may not exceed 34 mm SL. It is the only species in the genus, and related to Geophagus Heckel, and Biotodoma Eigenmann & Kennedy. No types were designated in the protolog, and consequently the later proposed holotype and paratypes are still syntypes. 37 specimens from savannah localities in Colombia (an affluent of the R. Yucao in the Depto.‐Meta, and a brook and laguna near the mouth of the R. Guarrojo in the Com. Vichada), show little intraspecific variation in body shape and coloration, although they extend the hitherto known variation. They agree well with the typical specimens as described by Myers & Harry (1948), but differ strikingly in having a principally biserial instead of triserial jaw dentition, and in a reduced premaxillary dentition. P. ramirezi is distinguished from all other cichlids in the following combination of characters: absence of gill‐rakers on the lower pharyngeal tooth‐plate, a small epibranchial lobe with marginal rakers, 25–27 vertebrae, a narrow preorbital bone, and a single supraneural spine. The species is specialised with regard to oral dentition and mouth shape. Individuals with more or less serrated preoperculum occur. Papiliochromis is the only endemic cichlid genus in the Orinoco basin. With four species of Apistogramma Regan, it is the only of 12 endemic cichlids that is not closely related to any non‐Orinocoan species. The species probably evolved in northern isolation from ancestors of its present‐day nearest relatives. The identity of a specimen from Bolivia, reported by Meinken (1967) as P. ramirezi, is strongly questioned. A group name, “geophagines”;, is proposed for neotropical cichlids with epibranchial lobe. A monophyletic group, but not subfamily rank is implied. Within this group are recognized two subgroups, viz. larger geophagines (Acarichthys, Biotodoma, Geophagus, Gymnogeophagus, Papiliochromis, Retroculus), and smaller geophagines (Apistogramma, Apistogrammoides, Biotoecus, Taeniacara).
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