Based on recent discoveries, Bujurquina appears to be the most widely distributed and species-rich cichlid genus in western Amazon of South America. In this study, using a large representative sample covering its whole distribution area, we use morphological molecular data test hypothesis that each major basin includes multiple endemic species arranged along an elevational river gradient these ...

A new cucullanid nematode, Dichelyne mexicanus sp. n., is described from the intestine of three species of fishes, Agonostomus monticola (Bancroft) (Mugilidae, Perciformes) (type host), Ictalurus balsanus (Jordan et Snyder) (Ictaluridae, Siluriformes) and Cichlasoma beani (Jordan) (Cichlidae, Perciformes), from three rivers (La Maquina River, Veracruz; Chontalcoatlán River, Guerrero and Santiag...

We have investigated the effect of mirror-elicited agonistic behaviour on oxygen consumption in the Mozambique tilapia, Oreochromis mossambicus (Cichlidae). Males exposed to their mirror image showed higher frequencies of both lateral display and tail-beating and escalated aggression more frequently than males exposed to a transparent glass that was used as a control for the presence of a novel...

The karyotypes of three species of fish of the Cichlidae family from the Forqueta river and several locations in Guaiba lake/RS (Brazil) were analyzed. All species presented 2n=48, while Gymnogeophagus gymnogenys showed two karyotypic formulae: 4m+44st-a with FN=52 and 6m+42st-a with FN=54. Gymnogeophagus labiatus presented 4m+4sm+40st-a and FN=56 and Geophagus brasiliensis 4sm+44st-a and FN=52...

Small circular spots of light were focussed on otherwise unilluminated retinas of paralyzed fish. C~c~~~rnu bi~e~~tu~ The retinas were sub~uently examined histolo~cally, and a small circular region was found within which the cones and pigmented retinal epithelium were photomechanically tight adapted; rods could not be resolved. The same result was obtained with the optic nerve cut. The region w...

The fish family Cichlidae has a large diversity and dominates African freshwater bodies, with over 200 species reported in inland waters. Sampling for the fish Oreochromis niloticus (Linnaeus) in Opa reservoir, Nigeria, started in October 1997 and extended until February 2000. The fishing methods employed for collecting the 1 430 specimens were cast netting and gillnetting. Egg diameter varied ...

The present study was based on the analysis of spraints (n = 294) collected between December 2005 and November 2007. The importance of each type of prey was determined by absolute and relative frequency. Niche breadth was also estimated. The results were reported as mean (± SD) of relative frequencies. Fish were the main prey found in spraints (57.8 ± 7.0%). Fish from Callichthyidae family were...

The South Asian Cichlidae are composed of two clades that together represent the sister group of the Madagascan genus Paretroplus Bleeker. Chaetodon suratensis Bloch and Etroplus canarensis Day are retained in Etroplus Cuvier, while Chaetodon maculatus Bloch is allocated to Pseudetroplus Bleeker. Pseudetroplus is distinguished from Etroplus in having, among other characters, 11 (vs. 12-13) pleu...