not mine.... just good research.... more to add later!!!!
by the way.... tongue33, this is going to be a very good thread leading into a sticky if everyone plays theyre cards right.....
One group of cichlids from South America has become well known the "peacock basses" of the genus
Cichla. They have even been introduced into Central America (and other tropical bodies of water) specifically for this reason. And what makes them great sports fish also makes them inappropriate for the home aquarium unless you have suitably large aquarium space available and are willing to accept the challenge of raising and attempting to spawn truly large cichlids.
These fish are on the short list of the world's largest cichlids, which they share with
"Cichlasoma" (
Nandopsis)
dovii,
"C." (
Nandopsis)
umbriferum, and that giant from Lake Tanganyika in Africa,
Boulengerochromis microlepis. Despite their imposing adult size and their rather restricted dietary preferences they are piscivores (fish eaters), although not exclusively so juveniles and subadults are still imported and made available for sale in pet shops.
While I appreciate the beauty of these fish, I cannot recommend them to any but the most dedicated (and perhaps foolhardy!) of South American cichlid aficionados who can provide the space and chow they need. Nevertheless, they have been kept successfully in aquariums, and therefore deserve coverage in this series.
I will do so in two parts, beginning first with the taxonomic and systematic status of these fish, including unfortunate conservation situations resulting from the intentional introduction of peacock basses into various parts of the tropical world to support sports fishing. If you find this dry, I apologize but hang in there for part two, in which behavior in the wild and maintenance in the aquarium will be covered.
How Many Cichla Species?
Again, we look to Kullander's (1986, 1989) recent reconsideration of the genus and 15 nominal species, of which only two names,
Cichla ocellaris and
C. temensis, are applied to
Cichla species in the aquarium trade. These include
C. argus Valenciennes 1834,
C. atabapensis Von Humboldt 1834,
C. bilineatus Nakashima 1941,
C. brasiliensis Schneider 1801,
C. intermedia Machado-Allison 1971,
C. monoculus (Spix 1831),
C. multifasciata (DeCastelnau 1855),
C. nigrolineatus Ogilvie 1966,
C. ocellaris Bloch and Schneider 1801,
C. orinocensis Von Humboldt 1834,
C. speciosus (Muller and Troschel 1849),
C. temensis Von Humboldt 1834,
C. toucounarai (De Castelnau 1855),
C. tucunare Heckel 1840, and
C. unitaeniatus Magalhaes 1931.
Of these, Kullander has boiled them down to five valid nominal species
C. intermedia,
C. monoculus (synonyms
C. toucounarai,
C. bilineatus),
C. ocellaris (synonym
C. speciosus),
C. orinocensis (synonyms
C. argus,
C. atabapensis) and
C. temensis (synonyms
C. brasiliensis,
C. tucunare,
C. unitaeniatus). But he suggests (Kullander and Nijssen 1989) that further study might expand this list to 11 valid species. Part of the confusion results from loss of the original holotypes the specimens used for classification due to World War II bombings of German museums, and/or lack of locational data.
For aquarists, the list of expected species includes
C. monoculus from Peru (possibly Ecuador, Bolivia and western Brazil, but these may be yet undescribed),
C. orinocensis from Venezuela and Colombia, the true
C. ocellaris from the Guyanas,
C. temensis from the Brazilian Amazon (and the Rio Orinoco, Machado-Allison 1973), and
C. intermedia, also from Venezuela. Of these,
C. temensis and all the other
Cichla species (all resembling the hobby "
C. ocellaris") are most easily distinguished.
With
Cichla temensis we have a relatively slender cichlid with much smaller scales (Kullander 1986) and a distinctive color pattern consisting of an overall gray-black body punctuated by three black vertical bars on the flanks and overlaid with light gold spots, at least as juveniles and subadults (up to 6 to 8 inches). Recent photos in Glaser and Glaser (1996) suggest that huge adult
C. temensis may actually lose the spotting. However, I've seen some freshly wild-caught (hook-and-line) Venezuelan
C. temensis, taken along with huge
C. orinocensis from the same location, that most definitely showed the characteristic spotting pattern and were easily identified. The American aquarist Jeff Cardwell (personal communication) has likewise taken both
C. temensis and
C. monoculus together in the Brazilian Rio Negro.
Cichla ocellaris and
C. monoculus are most similar to each other and, particularly as juveniles, share similar coloration principally three partial black vertical bars (or spots) on a brassy body color. Adult
C. monoculus, according to Kullander (1986), have wider and longer bars that extend from the point of dorsal fin insertion downward, in contrast to the appearance of those of
C. ocellaris.
According to Machado-Allison (1971), in adult
C. orinocensis three large ocelli (eye spots) replace the three vertical bars along the middle of the sides, whereas
C. intermedia (named as such because it is intermediate in color pattern between
C. temensis and
C. orinocensis) has numerous (more than three) short bars. (All
Cichla species sport a distinctive ocellus just above the middle of the base of the tail fin.)
However, identification based on color pattern is not that easy or reliable. Complicating this simplistic picture are the dramatic variations of color that accompany the widespread distributions of all of these species (i.e., see Kullander 1986 regarding
C. monoculus). Not only is the base color variable (olive green to orange to yellow), but the darkness of the bars and the extent of spotting on the back differs from population to population. I refer you to any of the following picture resources Axelrod (1993, though I dispute some of the identifications), Stawikowsi and Werner (1988), and, most recently and most particularly, Glaser and Glaser (1996) for a photographic stroll through the possibilities.
Actually, the most astonishing catalog of populational differences appears in Schomburgk's 1843 treatise on the fishes of Guyana. He recognizes and figures (all hand-colored prints!) no fewer than four "species"' of "
Cychla," as he calls them. Interestingly, he lumps the four pike cichlids (
Crenicichla sp.) he catalogs from Guyana in his genus
"Cychla." Indeed, several described "species" of
Cichla (e.g.,
chacoensis Holmberg 1891,
conibus De Castelnau 1855,
labrina De Spix 1831,
niederleini Holmberg 1891) have since been correctly reclassified in the genus
Crenicichla (Ufermann et al 1987).
Moreover, all
Cichla species experience profound changes in coloration as they grow to adulthood. For example, Kullander and Nijssen (1989) describe these changes for
C. ocellaris. Young fish up to about 2¼ inches sport three dark spots on their flanks (in addition to the tail fin ocellus) that then expand to become partial vertical bars. At about 2½ to 3 inches, spots develop on the back and sides, only to disappear at about 3½ to 4 inches. Specimens of 6 1/3 inches in length or longer develop an ocellated spot near the top in bar three (closest to tail). The color pattern continues to change as the fish continues to grow, and changes still further in reproductively active (courting and breeding) individuals.
Lowe-McConnell (1969) also noted developmental changes in coloration in this species. And Schroder and Zaret (1979) have described in detail the progression of patterns from two-week old larvae to mature adults. Similar color changes have been noted and described for
C. monoculus (Kullander 1986). Glaser and Glaser (1996) include photos of both juveniles and adults for a number of populations and species of
Cichla, and the developmental differences are often astonishing.
Schroder and Zaret (1979) believe that the initial "striped" pattern facilitates schooling behavior, and that when the fry disperse (11 to 15 weeks old) to begin a solitary existence in the vegetation along the shore, the barred juvenile pattern develops. Because the youngsters at this point in their lives are relatively stationary, rarely venturing out more than a few feet from the plants, the barred pattern serves them well as camouflage. At this point, the tail fin ocellus develops along with several (soft) dorsal fin ocelli.
Schroder and Zaret (1979) have described the dorsal fin erection display that small
C. ocellaris respond with to the approach of larger, potentially dangerous
C. ocellaris. They believe that the behavior and the ocelli facilitate recognition of others within the same species, and prevents cannabalism of juveniles by adult
C. ocellaris. The ocellus on the base of the tail fin apparently has another function, which we will review below.
We can certainly see the difference as the aquarium trade has done for years between
C. temensis and the rest of the species. The best we can hope to do with the others, assuming reasonable export information (e.g., Peru versus Brazil versus Venezuela versus Guyana), is to assign a tentative identification based on site of probable capture.
We would then refer to the specimens as
C. sp. affin.
monoculus or
C. cf.
monoculus if they came from Peru, with the "species affinis" or "cf." designation suggesting the probable rather than absolute identity of our fish. Even this may be going a bit far. Various species have been imported for aquaculture even within South America (e.g.,
C. temensis from Brazil imported into Guyana, Lowe-McConnell 1969) and possibly (probably) have been released into open water. Well, we can simply call them "peacock bass" as the sports fishermen do, or "tucunare" (Brazil) or "lukanani" (Peru) or "pavon" (Venezuela) as the native fishermen do!
Another interesting aspect of the biology of the peacock basses is that they seem unique in appearance, perhaps even "out of place" to the casual fish observer, relative to the other South American cichlids. In fact, no less than the American ichthyologist C. Tate Regan (1906) placed the genus
Cichla near the starting point for the evolutionary radiation of the South American Cichlidae, with
Cichla splitting off first from the ancestral New World cichlid, then the
Chaetobranchus/Chaetobranchopsis lineage, and finally the
Acara lineage, believed by Regan (1906) to be the "starting point for the evolution of the genera inhabiting South America."
And later, Regan (1920) intimated a possible link between
Cichla and the haplochromine cichlids of Africa based on the structure of the ventral surface of the neurocranium (skull) that provides a "movable joint" for the upper pharyngeal jaw (known as the pharyngeal apophysis). Indeed, Stiassny (1982) confirmed the
"Haplochromis"-type structure of the
Cichla pharyngeal apophysis, but interprets this shared structure differently than Regan (see below).
Kullander (1983), like Regan, regarded
Cichla as a primitive genus among more advanced cichlids. Liem (1973), too, regarded the "primitive" state of the pharyngeal jaw apparatus in
Cichla as evidence for this cichlid's overall evolutionary primitiveness.
Stiassny, however, has concluded otherwise. Rather than interpreting the "primitive" anatomy of
Cichla (and the closely related genus
Crenicichla pike cichlids) as evidence of their base position in cichlid evolution, she suggests that
Cichla (and
Crenicichla) are highly advanced cichlids. She develops that argument in a series of papers (Stiassny 1982, 1987, 1992) that constitute an exhaustive comparative anatomical study of
Cichla and various other evolutionary key New World and Old World cichlids.
In a nutshell, Stiassny argues that
Cichla, unlike the majority of piscivorous cichlids, swallows its prey whole rather than using the pharyngeal jaw apparatus to process the food. She cites observations by Pellegrin (1903) and Chichoki (1976) that juvenile peacock bass can and do take prey of up to one-third of their own length.
And, in specially preserved
Cichla specimens used for study, completely intact prey fishes are clearly visible in their stomachs. In swallowing prey whole,
Cichla (and the pike cichlids,
Crenicichla sp., which Stiassny believes is the sister group to
Cichla) are unlike the rest of the South American Cichlidae. Far from being a "primitive" cichlid, peacock bass should be regarded as highly specialized riverine predators that have secondarily acquired a set of seemingly primitive anatomical features that enable them to make use of relatively large prey fishes. The term "atavism," meaning "re-expression of ancestral morphologies," is used to describe the reappearance of a character state typical of a remote ancestor (e.g., the ancestor of all cichlids) in an individual that really shouldn't have it (e.g., a modern cichlid).
If Stiassny is correct (and I believe she is; her anatomical analyses are painstakingly detailed), this is another reason why the peacock bass have appeal for those aquarists who prefer large, predatory aquarium fish. And there's more. The peacock basses are some of the most beloved freshwater sports fish in the world.
And like people and animals.. Sun, earth weather... Mother nature in general has effects on living creatures and they look different in some way than there same species in other areas 
