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Butterflies And Peacocks From Lake Malawi

By , 1985. printer
Published
Paul V Loiselle, 2004

Classification: Species overview, Lake Malawi.

On more than one occasion (Loiselle, 1979, 1981), I have referred to the opening of Lake Malawi to the exportation of ornamental fishes as the "Malawi Revolution". My aim has been to dramatize the impact commercial exploitation of the Malawian fauna has had upon the evolution of cichlid keeping and of those organizations that have arisen to serve the needs of the cichlid-oriented hobbyist, such as the American Cichlid Association. As often happens when one coins a phrase to emphasize a point, accuracy becomes the victim of eloquence. The "Malawi Revolution" was actually a series of revolutions spread over nearly a decade, each stimulated by the sudden appearance of a new suite of desirable cichlids representing either a different area of the lake or else a previously unexploded component of its incredibly diverse assemblage of endemic species.

In retrospect, such a state of affairs is hardly to be marveled at. Lake Malawi is a very large body of water, whose abundant cichlid fauna is by no means uniformly distributed along its extensive shoreline. Logistic considerations alone would thus operate to limit the number of novelties exported at any given instant. The lake further comprises a number of discrete, often dramatically contrasted habitats. Each boasts its own distinctive assemblage of cichlids, whose capture in consequence poses a particular challenge to the commercial collector. Nor are the practical difficulties of marketing the cichlids characteristic of a given biotope limited to those attendant upon their capture. Packing and shipping techniques that work well for one group of cichlids may not (and often do not) guarantee success when applied to another. It is, thus, hardly surprising that the initial wave of mbuna to reach the outside world in the mid-1960's was initially followed by more mbuna rather than by a plethora of those haplochromine species associated with other habitats.

One interesting consequence of the initial attention devoted to the petricolous, or rocky shore associated, cichlids of the lake, such as the mbuna is the peculiar order in which Malawian Haplochromines made their aquaristic debut. As a general rule, the smaller representatives of a given group of cichlids are the first to become established in the hobby, if for no other reason than their space requirements are more easily met than are those of their larger congeners. However, the first Malawian Haplochromines to be exported in any numbers were the boldly marked juveniles of several large, often predatory species that could be collected and handled using many of the techniques employed successfully on the mbuna. In consequence, the first Malawian Haplochromine to be bred in captivity was Nimbochromis polystigma, a species both large and predatory! By the early 1970's, the selection of species generally available to hobbyists was so biased towards the larger representatives of the group that a forgivable perception had arisen to the effect that Lake Malawi was devoid of other Haplochromines phenotypes.

This misapprehension was dispelled in 1971 when a steady stream of small, brilliantly colored, haplochromines began to flow from the lake into the tanks of importers in North America, Europe and Japan. One of the earliest and most spectacularly successful of these newcomers was a brilliant blue Aulonocara species promptly (anh felicitously) christened the Malawi Peacock. This exercise in creative marketing proved so successful that the trade name of "Peacock" was further applied to a wide range of haplochromine species with little in common beyond modest adult size and spectacular male breeding coloration. In this essay, I will focus upon those cichlids to which this name was initially applied, the crepuscular, benthic invertebrate-feeding cichlids of the genus Aulonocara.

In 1921, the British ichthyologist C. Tate Regan erected the genus Aulonocara for a distinctive little haplochromine cichlid from Lake Malawi in which the bones of forehead, cheeks and lower jaw was characterized by a remarkable enlargement of the pores of the cephalic lateralis system, a prolongation of the lateral line readily visible on the flanks of this and most other fishes. To Regan, these remarkably enlarged opening resembled the holes in a flute, hence the derivation of the generic name from aulos, the Greek word for the instrument. Regan was struck by the degree of convergence displayed; this Malawian species and the Tanganyikan cichlids of the genus Trematocara with regard to this characteristic, though as he pointed out, the two taxa otherwise were quite different in appearance. Regan noted the presence of about ten narrow dark vertical bands on the flanks of his material and his figure depicts a fish with white dorsal fin lappets and a narrow dark submarginal band in the spiny dorsal fin. He also noted an interesting instance of sexual dichromatism that persisted in his preserved specimens. The ventral and anal fins were sooty in males, the latter fin clearly marked with orange spots, while in females the ventrals and anal were orange.

Aulonocara nyassae remained the unique species of its genus until 1935, when Ethelwyn Trewavas, Regan's successor at the British Museum, described two additional species, Aulonocara macrochir and Aulonocara rostrata (A. macrochir now considered a junior synonym of A. rostrata). Trewavas elaborated on Regan's description somewhat, noting that the enlargement of the suborbital bones associated with the enlargement of the cephalic lateralis pores in this genus was so marked it tended to crowd out the scales normally present on the cheeks in Malawian haplochromines. In the extreme case, the cheeks are entirely naked, but typically, the squamation in this area is reduced to a single row and part of a second row of scales. Her interest in this characteristic is understandable given her description of a new genus, Trematocranus, characterized by a moderate degree of enlargement of the cephalic lateralis pores and the presence of two to four complete scale rows on the cheeks. Trewavas, like Regan, drew a parallel between her new genus and a Tanganyikan cichlid, observing that Trematocranus stood in the same relationship to Aulocranus as Aulonocara did to Trematocara. As initially constituted, Trematocranus was a rather heterogenous assemblage of cichlids, comprising two rather long-snouted, laterally blotched species, Trematocranus microstoma and T. brevirostris and a single small, short-snouted laterally striped species, Trematocranus auditor. Trewavas, herself, suspected that T. auditor might prove unrelated to the other two species of the genus Trematocranus (Now auditor is considered part of the genus Aulonocara).

Apart from a brief consideration of the ecology of A. nyassae (Fryer, 1959), nothing was further added to available knowledge of these cichlids until their export began in the early 1970's. It then became evident that there were far more cichlids with enlarged cephalic lateralis pores swimming about in Lake Malawi than ensconced in labeled bottles in the British Museum. These were exported under various trade names, species with greatly enlarged cranial pores being referred to as Aulonocara, while those with a moderate degree of pore enlargement were marketed as Trematocranus. This rule of thumb, (extreme hypertrophy, Aulonocara; moderate enlargement, Trematocranus) even influenced the scientific description of several of these newly discovered species (Johnson, 1974; Burgess and Axelrod, 1973).

This comfortable point of view unfortunately does not correspond closely to a more rigorous evaluation of the relationships of Malawian cichlids. In his revision of the laterally spotted haplochromines endemic to Lake Malawi, Oliver (1977), found that Trematocranus microstoma, type species of that genus, shared a suite of specialized anatomical and colorational characteristics with two nominal Haplochromines species, Trematocranus placodon Regan 1921 and Trematocranus labifer Trewavas 1935 and the distinctive Hemitilapia oxyrhyncha Boulenger 1912. He united all of these species under the genus Hemitilapia, an action that relegated Trematocranus to the status of a junior synonym. Oliver also noted the heterogenous nature of Trematocranus as originally conceived and pointed out that three of the species originally placed within that genus were clearly misclassified. One of these, Trematocranus peterdaviesi Burgess and Axelrod 1973, he referred to the genus Lethrinops in view of its close affinities to Lethrinops gossei Burgess and Axelrod 1973 (peterdaviesi now classified under Alticorpus Stauffer & Mckaye, 1988). The two remaining species, Aulonocara auditor Trewavas 1935 and Aulonocara jacobfriebergi Johnson 1974 he effectively left in limbo pending further study of their relationships.

Having seen the type material of T. microstoma, I concur fully with Oliver's decision to place that genus in the synonymy of an expanded Hemitilapia. I would go one step further in his treatment of the species orphaned by this move and suggest that both Aulonocara auditor and Aulonocara jacobfreibergi can be accommodated within the Aulonocara without doing insupportable violence to the current concept of that genus (Editor note: This last was already done, 1997). These two species have been excluded from Aulonocara on the grounds that they display a lesser enlargement of the cephalic lateralis pores and have two complete scale rows on the cheeks in consequence. Against this essentially quantitative difference must be balanced a color pattern based on from ten to twelve narrow lateral bars, the presence of distinct white dorsal lappets, and of a dark submarginal band in the spiny dorsal. Such features are not common among the nominal Haplochromines endemic to Lake Malawi. They do occur often enough in the genus Lethrinops, but neither of the orphaned Trematocranus species possesses the distinctive buccal dentition and lower pharyngeal bone morphology characteristic of that genus. Indeed, insofar as these features are concerned, they are far more similar to the several Aulonocara species than they are to any other group of Malawian haplochromines. Pending the availability of additional data that would invalidate such an attribution, then, these two species are best referred to genus Aulonocara by aquarists.

Taxonomic knowledge of these cichlids at the species level is unsatisfactory even by Malawian standards. Of the five species to date described (Editor note: Now eighteen, 1997), only two, Aulonocara auditor, the Midnight Peacock of the aquarium trade, and A. jacobfreibergi, the Malawi Butterfly Cichlid, have to date been imported (1985). The Red-shouldered Peacock, first representative of the group to be exported from Lake Malawi, is actuality an undescribed member of the genus, not Aulonocara nyassae, while the species marketed as Aulonocara peterdaviesi bears not even a superficial resemblance to the true bearer of that name. An additional six to eight species are known only by one or more trade names, which typically vary from one side of the Atlantic to the other and show very little consistency even within the United States, a state of affairs that does little to facilitate the exchange of information about these extremely colorful fishes. There are several reasons for this regrettable state of affairs. Because they are typically found in habitats that render them difficult to collect, wild-caught specimens of the various Aulonocara command too stiff an asking price for importers to react very positively to the suggestion that they ought to sacrifice a dozen or so individuals in the interests of taxonomic progress. Once the fish begin breeding, there is no shortage of potential bodies to be had, but ichthyologists are justifiably wary of basing a species description upon aquarium-reared material. Finally, as the collectors of these fish are loath to make life any easier for actual or potential competitors than they must, they are generally reluctant to divulge their collecting rites to outside parties. Hence, even wild-caught specimens are usually devoid of reliable locality data, which most ichthyologists regard as an essential component of a proper species description. It, thus, seems likely that hobbyists with a fondness for these cichlids will have to live with a considerably less-than-ideal situation in this respect for some time to come.

Swallow-tailed Butterfly cichlid A male of the undescribed Aulonocara species marketed under the quite appropriate trade name of Swallow-tailed Buterfly cichlid. This spectacular newcomer from Lake Malawi is closely related to the more familiar A. Jacobfreibergi but is slenderer species with a more deeply emarginate caudal. Photo by Paul V. Loiselle.
Red-Shouldered Peacock A sexually quiescent male of the undescribed Aulonocara species to which the name Malawi Peacock was first applied. This species is now generally known as the Red-Shouldered. Photo by John Barbowski.
Red-Shouldered Peacock A fighting male Red-Shouldered Peacock. The suppression of the red humeral girdle is also characteristic of courting males. The enlarged cephalic lateralis pits give the head its distinctive textured appearance. Photo by Paul V. Loiselle.
Female Red-Shouldered Peacock A female Red-Shouldered Peacock. As is typically the case in haplochromine cichlids, juveniles and females sport little of the brilliant coloration of adult males. Prospective buyers of these fish should bear this in mind when evaluating a retailer's stock. Photo by Paul V. Loiselle.
Regal Peacock male A sexually active male Regal Peacock. Males of this undescribed Aulonocara species are darker than the Red-Shouldered Peacock but equally dazzling in coloration. Photo by Paul V. Loiselle.
Aulonocara sp. A male of the undescribed Aulonocara species marketed erroneously as Trematocranus peterdaviesi, a very different species properly referable to the genus Lethrinops. the alternative common name of Powder Blue Peacock is to be preferred for this beautiful cichlid. Photo by Paul V. Loiselle.
Aulonocara auditor young male A young male Aulonocara auditor, known in the trade as the Night or Midnight Peacock. This is the smallest representative of the genus currently available to aquarists, as well as one of the most easily bred. Photo by Paul V. Loiselle.
Aulonocara auditor female A female Aulonocara auditor. Females of this sexually precocious Peacock 5.5 cm SL have been observed carrying eggs. Photo by Paul V. Loiselle.
Sulfur-headed Peacock The Sulfur-headed Peacock exemplifies the difficulties entailed in drawing generic boundaries between Malawian cichlids. Elements of the male color pattern are suggestive of several Haplochromine species group, while the cephalic lateralis pores along the lower jaw display some degree of enlargement. Pending a clearer understanding of its relationships, this very desirable species is best referrer to the genus Aulonocara. Photo By Paul V. Loiselle.
Male Orange sided Peacock A male Orange sided Peacock. This undescribed Aulonocara belongs to a group of relatively long-snouted species that includes the to date unimported A. macrochir and A. rostrata. Photo by Paul V. Loiselle.
Female Orange-sided Peacock A ripe female Orange-sided Peacock. The combination of light dorsal margin with a darker submarginal band and numerous narrow dark lateral bars is characteristic of the genus Aulonocara. Photo by Paul V. Loiselle.
Male Flavescent Peacock A male Flavescent Peacock. This undescribed Aulonocara species is one of the most beautiful members of the genus. It is also one of the most challenging to keep and breed in captivity. Photo by Paul V. Loiselle.
Male Aulonocara jacobfreibergi A male Aulonocara jacobfreibergi. The aptly named Butterfly Cichlid has enjoyed enormous popularity ever since its initial introduction in 1972. The intensity of the golden ochre body coloration of this species is strongly influenced by the available of appropriate pigment precursors in its diet. Photo by Paul V. Loiselle.
Female Aulonocara jacobfreibergi This female Aulonocara jacobfreibergi displays the dorsal markings and lateral banding characteristic of the genus. Photo by Paul V. Loiselle.
Sunshine Peacock The Sunshine Peacock is my favorite representative the genus Aulonocara. Males such as this one inspired the highly descriptive common name of this justly popular species. Photo by Paul V. Loiselle.
Female Sunshine Peacock Female Sunshine Peacock are fairly distinctive in appearance and are unlikely to be confused with those of other Aulonocara species. Photo by Paul V. Loiselle.

The admittedly confused alpha-level taxonomy of this group has led a number of authors (Axelrod and Burgess, 1978; Mayland, 1982) to treat many of the commercially available Peacocks as morphs or color varieties of Aulonocara nyassae. Such usage is totally devoid of any supporting evidence and has led to a pernicious tendency on the part of neophyte keepers and commercial breeders of these fish to hybridize them indiscriminately. The result has been the introduction of a plethora of intermediate phenotypes into commercial circulation. In the short run, this has further complicated the problem of correctly identifying these cichlids, while posing the long-term risk that parental stocks will be genetically contaminated through backcrossing with such hybrids. Fanciers of these cichlids would be well-advised to adopt the attitude of killifish breeders, whose experience under comparable circumstances has taught them the wisdom of maintaining line-bred strains of all of the putative color varieties of a given species that come their way.

In any consideration of these cichlids, it is convenient to divide them into two major groups based upon their most obvious characteristic, the dominant color of sexually active males. The first group, to which the name Peacock Cichlid may be most appropriately attributed, consists of species in which dominant adult males develop an iridescent blue base coloration that positively eclipses the best efforts of their avian namesake. The blue Peacock group comprises the four following fish, as well as the yet to be exported A. macrochir:

  • Aulonocara auditor (Trewavas 1935), the Midnight or Night Peacock. This relatively small species begins spawning at 5.5 cm SL and seldom grows larger than 10.0 cm SL. Originally described from Vua, on the northwestern coast of the lake, it has also been taken from the Likoma Island group (Staeck and Linke, 1981).
  • Aulonocara sp. ­ Red-shouldered Peacock. This was the first representative of the group to be exported. Its dazzling coloration gave rise to the trade name of Peacock Cichlid, which, preceded by some distinguishing adjective, has subsequently come to be applied to any small Malawian haplochromine with a metallic blue base color regardless of its generic identity. The Red-shouldered Peacock can grow to 17.0 cm SL, but attains sexual maturity at c. 8.0 cm SL. It hails from the southeastern corner of the lake. As previously noted, this species has been confused with A. nyassae, a quite differently colored species which has not to date been imported (Axelrod and Burgess, 1978; Jackson and Ribbink, 1975).
  • Aulonocara sp. ­ Regal Peacock. This is another fairly robust species characterized by a uniform metallic dark blue coloration. It hails from Mbenji Island in the south-central part of the lake (Mayland, 1982; Staeck and Linke, 1981). The Regal Peacock matures at a somewhat smaller size than the foregoing species, males beginning to color up at c. 6.0 cm SL, while females as small as 5.0 have been observed carrying a mouthful of eggs.
  • Aulonocara sp. ­ Powder Blue Peacock. This robust species of unknown provenance has been widely marketed under the name Alticorpus peterdaviesi, which properly belongs to a very different species referable to the genus Lethrinops that has not to date been exported. Though it can grow to 15.0 cm SL, the Powder Blue Peacock is characterized by considerable sexual precocity. Males begin to color up at 5.0 cm SL and begin spawning shortly thereafter.

The second group comprises species whose body color ranges from tawny gold or bright yellow through rusty orange. Such blue coloration as these Peacocks possess is restricted to the head and fins. Six representatives of the tawny Peacock group have been exported:

  • Aulonocara jacobfreibergi (Johnson 1974), the Butterfly Cichlid. Males of this spectacular cichlid differ from the generality of Peacocks in their broad, iridescent white dorsal and caudal fin margins, a trait shared with the following species. Females have the same overall color pattern as do other Aulonocara species. Like the Red-shouldered Peacock, this species can grow as large as 17.0 cm SL, but attains sexual maturity at half that size. Johnson (1973) gives Makanjilla Island as the type locality of the Butterfly Cichlid.
  • Aulonocara sp. ­ Swallowtail Butterfly Cichlid. This recently imported species of unknown provenance differs from the foregoing in its slenderer body and in details of its color pattern. It displays marked sexual precocity, males developing their distinctive coloration and females spawning at c. 4.0 cm SL.
  • Aulonocara sp. ­ Orange-sided Peacock. The morphology of this relatively long-snouted species is reminiscent of that of A. macrochir and A. rostrata. It differs from those species in details of its color pattern. This is another relatively robust Peacock of unknown provenance.
  • Aulonocara sp. ­ Flavescent Peacock. This is one of the most vividly colored representatives of the genus to date imported, as well as one of the largest. Males can grow to 18.0 cm SL and do not begin to develop their intense coloration until they attain a length of almost 8.5 cm SL. As with so many Aulonocara species, its locality of origin has not been made public.
  • Aulonocara sp. ­ Sunshine or Yellow Peacock. This magnificent cichlid is one of the most spectacular cichlids to be exported from Lake Malawi. The Sunshine Peacock has been reported from the Maleri Islands in the southwestern arm of the Lake (Staeck and Linke, 1981) and from the Likoma Island group in its east central region (Mayland, 1982). A morphologically very similar fish with a brilliant metallic blue head, sold as the Yellow-sided Peacock, is reported from the Chindunga rocks, immediately to the southeast of Maleri Island off the village of Chipoke (Staeck and Linke, 1981). Whether this is a geographical race of the Sunshine Peacock or a different species remains to be determined. This is a relatively small species. I have never seen a male over 12.0 cm SL. Withal it is a slow maturing species, whose males do not begin to develop their dazzling coloration until they are at least 7.0 cm SL.

There are other species to which the Peacock designation is sometimes applied. Several Haplochromines species of the utaka group characterized by brilliant blue male breeding dress and a creamy white to yellow frontal blaze have been styled Ivory Peacock in the trade. These open-water living zooplankton feeders are not at all closely related to the genus Aulonocara and have a quite different lifestyle in nature, though the maintenance requirements of the two groups in captivity are quite similar. The affinities of some of the other cichlids whose coloration has earned them the Peacock name are not quite as easily determined. Notable among these is a relative newcomer to the ranks of commercially available Malawian cichlids. The so-called Sulfur-headed Peacock made its debut concurrently with the Swallowtailed Butterfly Cichlid in late 1981. Its classification poses something of a problem. In overall appearance, it resembles a Lethrinops species, but it lacks the characteristic buccal dentition of that genus. Contrary to the usual case in Aulonocara, only the cephalic lateralis pores of the lower jaw show a notable degree of enlargement. The color pattern of this species further contains elements more reminiscent of several Malawian Haplochromines than of the known representatives of the genus Aulonocara. I have elsewhere (Loiselle, 1982) suggested that the Sulfur-headed Peacock be tentatively referred to the genus Aulonocara until its relationships are better understood. Regardless of its generic placement, this is a strikingly colored and deservedly popular cichlid.

The pit-like structures present on the forehead, cheeks and lower jaw of these cichlids are such a conspicuous feature that some discussion of their function seems appropriate in any account of their biology. Such an effort is worth making in that an understanding of how Aulonocara species live in nature is likely to facilitate their proper maintenance in captivity. The lateral line system contains specialized cells, known as neuromasts that are sensitive to mechanical stimuli, notably the displacement of water in relationship to the animal that bears them. This sensory modality allows a fish to detect currents from a wide variety of sources, ranging from its own movements through the water right down to the very small displacements caused by a localized sound source. The lateralis sense thus plays an extremely important role in determining a fish's response to its environment. It allows it to detect prey and potential predators, maintain a hydrodynamically correct position in relation to currents, avoid obstacles, and even maintain correct orientation within a school. As Bond (1979) aptly notes: "These abilities would seem especially important among species of nocturnal habit or those living in caves or the deep ocean. The latter two groups certainly show great modifications of the lateral line organs, some even having them placed on ridges or papillae instead of in canals."

One might, thus, reasonably expect to find that such cichlids as display a marked enlargement of the cephalic lateralis system are characteristic inhabitants of the deeper waters of the African Great Lakes. Indeed, such an adaptation to life in an environment characterized by low light intensity has occurred several times in Lake Tanganyika where, in addition to the genera Trematocara and Aulocranus, a number of Lamprologus species are also characterized by greatly enlarged cephalic pores (Brichard, 1978). It should, therefore, come as no surprise to find that several different groups of Malawian cichlids have also responded to life in deeper water in this fashion. While the genus Aulonocara is unique in the degree to which this adaptation has been elaborated, other Malawian genera also include species characterized by some degree of cephalic lateral line pore enlargement. Mention has already been made of the genus Hemitilapia in this context, and I have seen specimens of several undescribed Lethrinops species that showed notably enlarged sensory pores on the cheeks and lower jaw.

The limited information available on the biology of Aulonocara species in nature clearly reinforces the notion that these cichlids are inhabitants of fairly deep water. Most species are collected within the 6 to 20 m depth range. Even in the clear water of Lake Malawi, light is sufficiently attenuated at these depths to confer considerable selective advantage to the elaboration of alternative sensory modalities such as the lateralis sense. Both their dental morphology and such information as is available from analysis of stomach contents (Fryer, 1959) suggests that Aulonocara species feed chiefly upon aquatic insect larvae, whose detection in a dimly illuminated environment must certainly be facilitated by an enhanced lateralis sense. Lake Malawi contains a number of large, deep-dwelling predatory catfishes, such as Bagrus meridionalis and a number of Bathyclarias species. These fish prey heavily on haplochromines of the same size as the various Aulonocara species (McKaye, 1983) and it is quite likely that they are very important predator of the various representatives of that genus as well. The extensively elaborated cephalic lateralis system of these cichlids may thus function as means of detecting the approach of predators in a poorly lit environment as well as a means of locating food.

Information on the habitat preferences of these cichlids is equally sparse. Such observations as have been published (Fryer, 1959; Staeck and Linke, 1981) suggest that those species that occur at the upper end of depth range frequented by Aulonocara, such as A. nyassae, A. auditor and the Yellow or Sunshine Peacock are characteristic inhabitant of the transition zone between the rocky and sandy littoral. Some deeper-dwelling species have been observed in association with rocky biotopes (L. Nau, pers. comm.), others trawled over open, sandy bottoms (David Herlong, pers. comm.). As none of the latter group of species appear to have been exported to date, one may for the moment regard the various Aulonocara species currently available through commercial channels as essentially petricolous cichlids and tailor approaches to their management accordingly.

The overall maintenance requirements of these cichlids do not differ meaningfully from those outlined in an earlier essay (Loiselle, 1979) for the generality of Malawian haplochromines. I would only emphasize as strongly as possible the importance of properly managing the nitrogen cycle in their tanks. Peacocks are at all ages exceedingly sensitive to nitrogen cycle breakdown products. Elevated nitrite concentrations will cause juveniles to lie off one by one with no apparent symptoms other than somewhat accelerated breathing to suggest that something is amiss. Adults exposed to comparable levels may develop the chronic irritation of the cephalic lateralis pores that leads to "hole in the head" disease. Continued exposure to such stressful conditions invariably results in their loss to systemic bacterial infections. A program of regular partial water changes is absolutely essential to the well-being of these cichlids in captivity. The replacement of 40% to 50% of their tank's volume every seven to ten days is by no means excessive. An easily cleaned high capacity outside power filter is also a very helpful adjunct to their successful maintenance. It should be charged with an efficient, reusable medium such as Eheim's EhfiFix™ and the medium purged whenever it begins to look dirty. If the fish are maintained in a densely stocked community aquarium it is also prudent to keep a chemically active filter medium such as Poly-Filter™ in the unit at all times.

Careful selection of their tankmates also contributes to keeping the stress to which Peacocks are exposed at acceptable levels. Because they are characteristically associated with rocky biotopes in Lake Malawi, there is a prevalent tendency for aquarists to confound Peacocks with the various mbuna. This leads them to assume that representatives of the two groups can invariably be housed together with success in captivity. Such an interpretation is quite erroneous and can lead to unfortunate consequences. First of all, Peacocks are not at all closely related to the mbuna. It hardly requires a graduate degree in ichthyology to appreciate this fact, which should be evident to anyone with a functioning sense of vision. It should thus come as no surprise to discover that these cichlids are as different from one another behaviorally as they are morphologically. Peacocks are neither as hyperactive nor as aggressive as the majority of mbuna. Secondly, if one remembers that as group, the mbuna comprise an assemblage of cichlids defined largely by morphological features which allow them to efficiently graze the algal cover that carpets the rocky littoral of Lake Malawi, it should also be obvious why there are unlikely to interact very often with Aulonocara species in nature. Algae require strong light to flourish. In Lake Malawi, this effectively limits their distribution ­ and that of those fish that feed upon them and their associated invertebrate fauna ­ to the upper three to five meters of the water column. As we have already seen, Peacocks are invertebrate feeders that characteristically live at depths in excess of three meters in the lake. Interactions between mbuna and Aulonocara species in nature are thus minimal. One can thus hardly argue that the two should be housed together in captivity on the grounds that to do so is to replicate conditions in Lake Malawi. Unless one has access to very large aquaria, 400 1 capacity or larger, keeping Peacocks together with the larger mbuna species is unlikely to prove beneficial to the Aulonocara, who will find themselves in a state of perpetual subordination to their more frenetic tankmates.

It is always unwise to house more than a single Aulonocara species per aquarium and a positive invitation to disaster to attempt condomicilation of two species with very similar male breeding dress. The best outcome to be anticipated from the latter course of action is the permanent subordination of one male to the other. The worst is the death of the less assertive of the two contestants. Either will be followed in very short order by an inevitable hybridization episode as the sexually frustrated female of the subordinated or defunct male seeks what satisfaction is available to her from his persecutor. If the fish in question are respectively members of the blue and tawny groups, male coexistence may result, but there is always the possibility that the heterospecific male will attempt to join the consorting couple during the actual spawning act. If he is even minimally successful, the female's brood will comprise a mixture of genetically uncompromised and hybrid progeny. Males of such a mixed lot of fry will be virtually impossible to distinguish until they attain sexual maturity, while given the great similarity of Peacock females to one another, there is no guarantee that hybrid females will be detectable even then. There is always some element of risk that hybridization will occur on a small scale when Malawian cichlids are housed in a community situation.

However, if the species in question are quite different from one another in color pattern or morphology, such hybrids as are produced at least stand to be recognized as such in time to prevent their inadvertant dissemination. The foregoing caveats apart, Peacocks can be housed with a wide range of other Malawian cichlids. If the tank in question is sufficiently large, they may even be kept with some of the larger predatory Haplochromines with minimal risk. Most aquarists prefer to house them with other haplochromines of the same overall size, such as the various utaka. Given their small mouths relative to their body size, Peacocks are not very formidable piscivores. They can, thus, also be kept in company with any midwater living fish too large for them to easily swallow with minimal risk to their companions. Indeed, a trio of these cichlids makes a very pleasing addition to a traditional community tank stocked with the larger characoids and cyprinids.

Like the mbuna, Peacocks appreciate a tank that offers them ample shelter. Staeck and Linke (1981) have noted that male Aulonocara typically display at the entrance of a cave or grotto in nature. Aquarists with a bent for aquascaping will doubtless relish the opportunity to recreate such an environment for their fish. Those whose views relative to tank furnishings are more utilitarian in nature will rejoice to learn that an 8" clay flowerpot placed on its side will be seized upon as enthusiastically by a male Peacock in search of a territorial focus as the most carefully crafted display of rockwork. Unlike many other Malawian haplochromines, Peacocks are not plant eaters, nor are they greatly given to earthmoving when sexually active. It is, therefore, possible to keep them in planted aquaria with minimal risk to the flora. However well they may be adapted to life in a dimly lit environment Aulonocara species seem quite at home at the light levels required to support the growth of live aquatic plants. Such an arrangement, while hardly evocative of the environment these cichlids inhabit in Lake Malawi is, nevertheless, quite pleasing to the eye.

Peacocks are easily fed. They take any of the usual live and prepared feeds readily. Frozen chironomid larvae (bloodworms) and chaoborid larvae (glassworms) are particularly relished. So are live Tubifex worms, but the strong correlation between continual consumption of such food and the incidence of systemic bacterial infections in these fish suggests that the prudent aquarist would do well to omit them from the menu. The rapidity with which these normally bottom-feeding cichlids learn to take floating flakes and pellets from the surface of the water offers strong testimony to the behavioral flexibility of cichlids with regard to their mode of feeding.

So long as they are maintained under conditions that allow males to hold a territory from which they can display actively to potential spawning partners, Peacocks will breed quite readily in captivity. Male courtship is prolonged and can be very vigorous. Not even a good photograph can do justice to the brilliance of a courting male's coloration, which must be seen in person to be fully appreciated. The energetic character of a male's suit argues strongly that Aulonocara are best maintained in single male, multiple female groups or at the very least, that spawning be attempted in a community situation (Loiselle, 1983). Apart from a marked predilection for breeding within an enclosed space, Peacocks spawn in essentially the same manner as do other Malawian haplochromines (Loiselle, 1979). It is particularly important that the spawning tank be well furnished with shelter, as males will continue to drive females for several days after spawning has been completed. Ovigerous females seem less tolerant of such harassment than are those of many other mouthbrooders. Their usual response to such untimely male attention is to abort the incubation sequence by eating their brood. Such an outcome is also likely if they are moved to a nursery tank immediately postspawning. Such a disappointing outcome is less likely to occur if one defers such intervention for at least three days. Hence the importance of giving ovigerous females immediate protection from their erstwhile consort's attentions. Even under optimum conditions, young females may prematurely terminate the incubation sequence, but such behavior is typically outgrown after a few failures.

The yellowish-white to beige pyriform eggs measure 2.8 mm to 3.7 mm along the major axis, depending upon the age of the female. Spawns range from a dozen to four score eggs. The developmental interval is twenty-one days at 28°-30°C. The fry measure 10.0 mm-12.0 TL at release and have no difficulty managing Artemia nauplii and finely divided prepared foods for their initial meal. The female will continue to care for the fry for several days after their initial release. However, her presence is not essential under aquarium conditions, while her extreme protective attitude towards the fry may result in them spending time in their mother's mouth that could be better spent foraging. Hence most breeders separate mother and offspring as soon as the latter are fully mobile. Some breeders recommend a reconditioning period for the female before returning her to the company of other fish. If she is to be replaced in a community situation, I have found that simply disturbing the existing social order with a large water change and rearrangement of the tank furnishings suffices to give the female all the protection she requires during her re-entry to group living. As previously noted, the growing fry are very sensitive to dissolved metabolites, but apart from this, their rearing poses no serious difficulties. Growth rates vary between species. Sexually precocious species such as A. auditor, the Powder Blue Peacock and the Swallow-tailed Butterfly can, under ideal conditions, begin spawning by their sixth month postrelease. In most cases, however, the fish must be ten to twelve months old before attaining reproductive competence. Sexually related size differences are evident as early as the sixth week postrelease, however, a factor that should be taken into account when culling fry. If only the largest individuals are reared, the end result is apt to be a tankful of males.

Given their modest adult size, ease of maintenance and vivid coloration, it is hardly surprising that the various Aulonocara species revolutionized existing conceptions about Malawian cichlids as dramatically as the advent of the mbuna revolutionized established ideas about cichlids as a group. Virtually the only shortcoming from which these fish suffer is a less-than-exciting juvenile color pattern that does nothing to enhance their appeal to prospective owners. However, the hobbyist who takes the leap and purchases a group of these nondescript little cichlids will find his act of faith amply rewarded. Just as their lepidopteran and avian namesakes grow from drab infancy to glorious adulthood, so do the Butterflies and Peacocks of Lake Malawi metamorphose from undistinguished fry into some of the most brilliantly colored of all fresh-water fishes.

Literature Cited

  • Bond, C.E. 1979. Biology of Fishes. W.B. Saunders Co., Philadelphia
  • Loiselle, P.V. 1979. An aquaristic overview of the genus Haplochromis. II. The Malawian species. F.A.M.A. 2 (1): 42-47 et seq.
  • Loiselle, P.V. 1982. What's New from Africa? Postscript. Buntbarsche Bull. (93): 16-17.
  • Loiselle, P.V. 1983. Techniques for breeding polygamous cichlids. I. General management options. F.A.M.A. 6 (3): 14-20 et seq.

References (12):

Citation

Loiselle, Paul V. (October 07, 1997). "Butterflies And Peacocks From Lake Malawi". Cichlid Room Companion. Retrieved on December 16, 2018, from: https://www.cichlidae.com/article.php?id=63.

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