Colour forms of Amazonian cichlid fish represent reproductively isolated species

Abstract

Laboratory mate choice experiments have confirmed species status for cichlid fish in the African Great Lakes that differ in colour and little else. Colour differences between allopatric populations of the South American cichlid genus Apistogramma are known for many species, yet the status of such populations has not been previously tested. Analysis of the genetic relationships and mate choice characteristics of populations previously described as Apistogramma caetei from eastern Amazonia indicates genetic differentiation into at least three allopatric lineages, which also show strong prezygotic isolation through female mate choice, confirming them as Biological species. If future studies confirm that this result is indicative of a general trend, the species richness of the South American cichlid fishes may presently be seriously underestimated.

Color changing and behavioral context in the Amazonian Dwarf Cichlid Apistogramma hippolytae (Perciformes)

“…Baerends & Baerends-van Roon (1950) describe color patterns in several species of cichlids, but scarcely relating these changes to specific behaviors. Other studies examine relationships between color and behavior, but strongly directing the observation to specific behaviors, like social status (Barlow, 1973;Falter, 1987;Barlow & Siri, 1994;Korzan et al, 2008), sexual selection (Beeching et al, 1998;Römer & Beisenherz, 2005), or intra- (Baerends, 1993;Hurd, 1997) and interspecific communication (Ready et al, 2006). In addition to the cichlids, some studies address changes in coloration related to sexual selection of females in three-spined stickleback, Gasterosteus aculeatus (Rick & Bakker, 2008); for camouflage in the chamaeleon characin, Ammocryptocharax elegans (Zuanon et al, 2006); and in the larvae and juveniles of white sturgeon Acipenser transmontanus (Kynard & Parker, 2005).…”

Molecular characterization of relatedness among colour variants of Asian Arowana (Scleropages formosus)

“…The external colour patterns of fishes have been used widely to refine systematic identification of closely related species in highly vivid (Ready et al, 2006) (Hypoplectrus), some coral reef fish (Puebla et al, 2008), and Lemon damsel fish (Drew and Barber, 2009). Species or strain identification based on colour variation can sometimes be misleading however, with colour being a phenotypic plastic trait as has been observed in a coral reef fish, Pseudochromis fuscus (Messmer et al, 2005).…”

Apistogramma ortegai (Teleostei: Cichlidae), a new species of cichlid fish from the Ampyiacu River in the Peruvian Amazon basin

“…Morphologically, all three species possess the characteristics of A. caetei (see Kullander, 1980), and have no diagnostic characters for species delimitation other than details of coloration. Ready et al (2006) suggest that these species probably are still going through a process of speciation, following a recent allopatric divergence. Ready et al (2006) conclude that the species studied present genetic structuring, but little morphological variation.…”

“…Ready et al (2006) suggest that these species probably are still going through a process of speciation, following a recent allopatric divergence. Ready et al (2006) conclude that the species studied present genetic structuring, but little morphological variation.…”

“…There is, however, at least one cryptic group of species with minimal color differences but diagnosable by molecular characters, described by Ready et al (2006). They analyzed Apistogramma populations of eastern Amazon from four localities, and recognized genetically three species within what has been described as A. caetei.…”