(This article was originally published in "Buntbarsche Bulletin" 176 pp. 1-8 and 177 pp. 1-9 the journal of the American Cichlid Association, please consult the ACA home page for information about memnbership. It is here reproduced with the permission of author Peter A. Lewis).
Over my 30 years of being involved with the tropical fish hobby and, in particular the maintenance of fishes from the family Cichlidae, I have always found myself drawn toward the smaller species as opposed to the real "Guapotes" of the cichlid world. As a result, when the first shell-dwellers began to be exported from Lake Tanganyika during the mid-1970s a few species inevitably found their way into my collection. At the time the two most common were Lamprologus ocellatus and L. ornatipinnis. Today, however, a totally different scenario exists with many species available within our hobby that fall under the generic description of "dwarf shell-dweller."
Unfortunately, with the increased availability of species from many shoreline areas of the Lake, comes the unavoidable confusion associated with new imports as trade names and location identifiers are used to differentiate these new imports to our shores. For example, a new shell-dweller became available that, for several months, was being sold under the name of "pearly ocellatus" which was later identified as Lamprologus meleagris Buscher 1991, the "lace Lamprologus" and yet I still see fish lists with both. When acquiring a species new to your collection, it is important that the source is a reputable dealer or breeder or hobbyist who has a genuine knowledge of the provenance of the young specimens being provided. While not always possible it is preferable to purchase mature adults and rely upon your own knowledge of the species to establish their true identity.
Before discussing the individual species that may be classed as "shell dwellers", we need to first consider the question of the genus "Lamprologus" The last review of Lake Tanganyika's cichlid fauna appears to be that undertook by Professor Max Poll in 1986 in his paper published in the Academie Royale de Belgique. In this review Poll rejected the restrictions placed upon the genus Lamprologus by Columbe and Allgayer who defined Lamprologus as those species found in the Zaire River and who erected three new genera of Tanganyikan cichlids, namely Neolamprologus, Paleolamprologus and Variabilichromis. As an alternative Poll organized the 57 accepted genera collected from Lake Tanganyika to date into 12 tribes that appeared to share a common ancestry and rejected two of the three genera proposed by Columbe and Allgayer, these being Paleolamprologus and Variabilichromis. Poll did, however, retain Neolamprologus and the rehabilitated genus Lepidolamprologus as proposed by Pellegrin in 1904. However, in common with Loiselle, I feel that Poll's study was superficial at best and while I certainly can agree with such reclassifications as placing Lamprologus calvus and L. compressiceps into the new genus Altolamprologus, I cannot see the reasoning behind placing such cichlids as N. tretocephalus alongside N. multifasciatus as being in the new "Neolamprologus" genus. In my estimation, the genus Neolamprologus has now become the "miscellany" genus into which any Lamprologine is placed until further studies can be done to justify a more correct placement. For this article, rather than merely revert back to the catch all genus of Lamprologus I propose to use the list published by Mark Smith 1995 in the Fall issue of Aquarium Frontiers as a compromise to placing everything back into the Lamprologus genus.
Cichlids classed as shell-dwellers all appear to originate from the coastal waters of Lake Tanganyika, inhabiting the sandy littoral zone at depths ranging from 15 - 90 feet (5 - 30 m), with a bottom comprising fine sand or mud littered with the empty shells of the snail Neothauma tanganicensis. These fish congregate around and use the shells as a source of both shelter from predators and a site for egg laying and brood tending by the female. Of particular interest are Lamprologus signatus and Neolamprologus brevis, both species having been confirmed at depths down to 150 feet (50 meters). Their natural food is small invertebrates and freshwater shrimp in particular, and as such in captivity each species will relish a feeding of Cyclops, Daphnia or live brine shrimp.
The temperature of Lake Tanganyika remains stable year round at approximately 80°F (26.5°C). In an aquarium, clean, well-aerated water at a temperature of 77 to 82°F (25 - 28°C) is preferred with a pH between 7.8 and 8.8. Hardness may vary from 500 - 600 ppm TDS. Water changes amounting to 25% every 14 to 21 days are appreciated by these otherwise undemanding cichlids. Excessive water changes can, however, be detrimental especially if the aquarium contains fry younger than four weeks of age.
All the cichlids from Lake Tanganyika that are classified as "shelldwelling" and that show a definite preference for living around and spawning in vacated snail shells are known as "ostracophilic" cichlids, the description being derived from the Greek and merely meaning "shell loving." To date most of the cichlids that fall under this description belong in the genera Lamprologus, Neolamprologus and Telmatochromis of which it appears that T. burgeoni Poll 1942 is the only currently identified species of its genus that appears to be obliged to inhabit a territory strewn with empty snail shells.
If a breeding colony containing several fish is to be established, then it is recommended that at least one square foot of "floor space" should be allowed for each male and that at least one shell is available for each fish in the colony. While not always the case, many of the shell dwelling cichlids have adopted the practice of burying their shells until only the opening remains. This practice is more evident with wild imports and is often a key to spawning when all else fails. Ideally the tank floor should be covered with 2 to 3 inches (5 - 7.5 cm) of very fine gravel, preferably clean sand, such that each species may practice what comes naturally and bury their shell, the theory being this is to give added security from detection and prevent theft by such large cichlids as Lamprologus callipterus, an inhabitant of the same zone that has been observed carrying inhabited shells off in it's mouth back to it's own territory.
This gravel or sand substratum should be fine. Coral sand is adequate but silver sand is ideal. The water should be clean and well aerated using an appropriate air-operated sponge filter in the tank corner. Undergravel filters should be avoided since most shell dwellers spend tireless hours rearranging the gravel or sand in an aquarium only to result in exposing the filter and total disruption of the filter's effectiveness.
If a tank is to be established with no sand or fine gravel as substratum, then each shell should be placed on a shallow saucer full of sand to cater to the needs of these cichlids to excavate around the shell. Personally, I have witnessed an adult male push a shell as long as itself a distance of three inches across a sandy floor until the shell was positioned as the male required. Typically the fish will either excavate beneath the shell causing the shell to subside until all but the opening is apparent or cover the shell with sand, mouthful by mouthful or grain by grain, until the same result is achieved. A trick to removing these fish from their shell, without also taking the shell from the aquarium, is to place a nine-inch length of plastic pipe full of sand upright in the tank such that the shell can be placed on top of this pipe and yet still be fully submerged. Eventually the fish will leave the shell only to note its new position and to return to the floor of the aquarium where it feels more secure. The empty shell can now be removed from the top of the pipe and the fish caught, provided no other suitable refuges exist.
Keys to Successful Breeding
The majority of shell dwellers are aggressive, territorial, dwarf, conchicole, cichlids. They have a spawning routine that can be characterized by either weak pair bond formation between male and female as part of a colonial breeding and social structure or as a harem situation with one male serving a loose colony of four to five females that each preserves her own territory within the overall territorial boundaries established by the male.
Being typical cichlids, many of the shell dwelling species will often fight to the death if territorial squabbles erupt or if the aquarist attempts to establish a single colony containing several pairs but provides an inadequate number of shells. A sure sign that a particular fish is being shunned is the persistent evidence of this fish in one of the upper corners of the tank, this fish will not dart for cover when disturbed and will rarely be allowed to feed. To prevent the death of this fish, usually a male, it should be removed and placed in an alternative aquarium.
Water conditions are not critical but should be in the middle of the range preferred by the species in question since the coastal conditions of Lake Tanganyika are not too variable. Provision of suitable water is rarely a problem. An appropriate starting point would be water at 78°F (25.5°C) with a pH of 7.8 and a hardness in excess of 10 dGH. An essential element with most of the species covered is the provision of adequate empty snail shells of a suitable size. If a true colony is to be established then the aquarist must provide at least one more shell than there are fish in the tank. It appears that most species will continue breeding until the tank is saturated with offspring and mature breeding pairs. Once this stage is reached, the aquarist has to merely thin the population by taking out a few dozen shells, which are bound to contain fish or fry, and replace them with empty shells and set up another colony in a fresh tank using the displaced fishes to begin a new colony. Spawning can often be initiated by a water change coupled with an increase in temperature by two or three degrees above the aquarium norm. I will provide descriptions and breeding tips for eleven known shell-dwelling species.
Lamprologus kungweensis Poll 1956.
Lamprologus kungweensis male. Photo by Peter A. Lewis.
The shape of this cichlid appears enough to place the fish in the meeli/hecqui group of shell dwellers. A characteristic that will allow the hobbyist to readily identify L. kungweensis is the distinct yellow-gold line that runs across the top of the eye of both male and female, this line becomes apparent as each fish matures and highlights the "eyebrows" of both sexes. I do not believe that L. kungweensis is a geographical variant of Neolamprologus hecqui but is rather a distinct species that occurs along the shoreline of the lake in close proximity to the Kungwe mountain range, hence the specific name given to this cichlid.
Mature fish reach a standard length of 2.5 inches (6.25 cm) with the female remaining slightly smaller than the male. Sexing the L. kungweensis is not easy, the female of a mature pair is likely to be smaller than the male and her colors and markings are slightly less intense. Shells are readily accepted as both shelter and an egg depository.
I have been keeping six specimens furnished with several shells in a tank that is heavily overgrown with Java moss but that has but a scattering of fine gravel on the base of the tank. Since the L. kungweensis cannot even attempt to bury their chosen shells I was intrigued to see they adapted to what was offered in that each cichlid actually pulled a covering of the Java moss across the opening of the shell thus providing a degree of camouflage and security. It was not until I moved this mossy covering from the front of one of the shells to take unobstructed photographs of the fish that I realized what was taking place since within minutes of my moving the Java moss the cichlids were just as quickly grabbing mouthfuls and pulling the growth back across the front of their shells.
A distinct pattern change takes place when these cichlids are breeding in that the normal blotch pattern across the flanks of L. kungweensis becomes darker and the blotches become larger, extending into the base of the dorsal fin. Additionally the face and forehead of the male become dotted with an irregular pattern of small black spots across the normal grey background. L. kungweensis appears most comfortable when given shells for shelter and in which the female may deposit her eggs. A female will signify her willingness to spawn by quivering at the mouth of her chosen shell until such time as she can hold the interest of a male at which point she will enter the shell, deposit her eggs and then withdraw to allow the male to fertilize the new eggs. The shells I used were large enough to allow the male to enter which he dutifully did and presumably fertilized the eggs since, some seven to eight days later, a group of tiny fry could be seen gathering at the entrance to the shell. The female took on the role of caring for the fry and would actually carry strays back to the shell in her mouth should they wander too far from the sanctuary of her shell. The male did not appear to have a monogamous attachment to the female but would assist in keeping conspecifics from the area of the female's shell. The fry were large enough to take newly hatched Brine shrimp and sifted Daphnia as their first food in addition to finely powdered, freeze dried Krill. While the number of fry from each spawn was as few as 15 and as many as 28 the survival rate was high since the young would disappear into the heavy growth of Java Moss as soon as they were able to fend for themselves.
Lamprologus meleagris Buscher 1991. The Lace Lamprologus
Lamprologus meleagris, male. Photo by Peter A. Lewis.
This diminutive cichlid is a most attractive addition to the species of shell dwelling cichlids that have been introduced to the United States. Originally sold as the "pearly ocellatus," L. meleagris is an attractive silver-black cichlid that rarely exceeds 2.5 inches (6.25 cm) total length with flanks that are specked with a series of irregular, iridescent pearl-like spots that highlight the scales and fins of the fish. The flanks also show a purple undertone. At the lower edge of the operculum is a distinct black ocellus that is edged with blue along its leading edge. The throat of the cichlid is silver with just a hint of blue and the eye is highlighted with a bright blue band across its upper edge. Females can be up to 0.5 inches (1.25cm) smaller than males and their colors are not as intense, even when breeding.
Lamprologus meleagris, female with fry by shell. Photo by Peter A. Lewis.
Breeding seems to pose few problems unless too many L. meleagris are allowed to inhabit the same aquarium at which point cannibalism will occur as parents vainly try to protect their young from other inhabitants of the tank. My method is to place a pair, previously chosen by observing several individuals in a communal situation in a larger tank, into a 15-gallon (57-liter) tank decorated with rocks, waterlogged driftwood, a two-inch (five-cm) deep layer of gravel and three or four suitably sized shells. In a very short time the pair will have explored the tank, pushed, pulled or otherwise cajoled the shells to where they want them in the tank and set about the business of raising a family. The male appears to enter the shell only to fertilize the eggs after which he is content to leave the hatching of the eggs to the female. Since L. meleagris are so secretive about the spawning act and no obvious color changes take place the first sign that spawning has been successful is usually heralded by the appearance of several 0.25-inch (6-mm) fry at the mouth of the female's shell. The fry are unique in that they have a distinct redbrown pattern of bars across their body against a grey-white background. Once the fry have emerged the male then takes his turn as caretaker and will aid the female in defense of the shell. As the fry become more adventuresome the male and female prepare a small pit outside the shell in which the fry were born and it is here that the fry are encouraged to stay rather than being allowed back into the shell for shelter. Mature parents will not bother their progeny which will slowly establish their own territory within the breeding tank as space and decorations allow.
Lamprologus ocellatus Steindachner 1909
Lamprologus ocellatus, golden female. Photo by Peter A. Lewis.
A stunning 2.0 inch (5.0 cm) cichlid with a specific name that means "eye spot," deriving from the very distinctive gold outlined spot on the fish's operculum. The fish was originally described as Julidochromis ocellatus and as Lamprologus lestradei Poll, 1943, but rarely are these names used in articles concerning this popular shell dwelling cichlid. Endemic to Lake Tanganyika's Tembwe bay, Kigoma, L. ocellatus appears to be restricted to the coastal regions where the muddy or sandy shores are littered with empty shells of the snail, Neothauma tanganicensis. This cichlid has a distinct, gold colored iris to the eye, an eye spot on the ocellatum and a golden-cream colored body. It is usual for the male to be more intensely colored than the female. Only the edges of the fins are colored, the body of each fin being clear, spackled with blue or gold but lacking any pattern. The anal fin possesses seven to nine spines, a fact which can be used to distinguish L. ocellatus from other similarly colored species.
Rene Krüter who discovered this variant at Nundo Point in Zambia also has introduced a gold form into the hobby. This color morph has a very distinctive, golden-yellow sheen to the scales along the side of the fish, making this cichlid even more attractive. A discrete feature of the golden morph is a golden brown "skull cap" that sits across the head of the fish, between the eyes. The most distinctive feature of a mature pair of L. ocellatus is their size difference in that a full-grown male will be 2.0 inches (5.0 cm) standard length while his mate is likely to be barely 1.5 inches (4 cm) in length. The dorsal fin of the male golden variant L. ocellatus is edged with an orange-red band while that of the female is clearly paler, often white trimmed. Further the soft rays of the anal fin of the female are lacking in color. Mature females are shorter in the body than males and exhibit a more rounded belly while males have longer bodies that are best described as oblong in shape. A personal observation is that the teeth of mature males appear larger and more prominent than those of the females.
L. ocellatus is a colonial cichlid in nature, a male and several females occupying a small territory, usually no more than 12 inches (30 cm) in radius, around their chosen shells. Their digging behavior rivals that of the larger South American cichlids and it is usual for a colony to totally rearrange the substrate around their territory to establish a mound of sand as border to their domain. Konings (1988) in his video "Tanganykan Cichlids" suggests that the motivation behind this reconstruction is to provide a rampart at the edge of their territory and also to create a catchment area that diverts the natural flow of water and plankton, on which such shell dwellers feed, to the vicinity of their shell and their fry. For an in depth discussion on the living, hiding and spawning behavior of L. ocellatus within the confines of a discarded shell the reader is referred to Paulo, 1986.
Breeding is quite straightforward and can be accomplished with only a pair in a 15-gallon (55 liters) aquarium with a fine substratum and several clean, empty snail shells available as both a refuge and a spawning site. A pair can be conditioned on the usual good quality flake foods in addition to several feedings of such live foods as newly hatched Brine shrimp, Daphnia and Cyclops. Further the occasional helping of White worms or Grindal worms are appreciated.
An aquarist fortunate enough to witness the spawning act will see that the female, who may darken across the top of her body, will court the male by curling her body and tail slapping in his direction. She will then swim into her chosen shell, deposit a few eggs then retire in order for the male who will either enter the shell also and deposit his milt or, more likely, merely deposit his milt at the mouth of the shell if it is too small for his body, such that the turbulence caused by the female reentering the shell will draw milt into the shell and thus fertilize the eggs. Once the spawning ritual is complete, the female occupies her time fanning her pectoral fins across the entrance of the shell to ensure fresh, oxygenated water enters the shell and discouraging any itinerant snail or other unwelcome visitors from entering the shell and disturbing the spawn. At this point the female also becomes intolerant of the male and is likely to drive the male away as she would any intruder if he approaches too close to her shell. In a communal situation the male is likely to do no more than search out another female with whom to breed.
The eggs are white colored and about 0.5 inch (1.5 mm) along their largest axis. Such observations can only be made by completely and carefully destroying the shell in which spawning occurred at the risk of losing the whole spawn. Hatching occurs after 72 hours at 80'F (26.5'C) and the fry are free swimming some four six days later. It is worthy of note that the fry are not completely colorless but feature a distinct black wedge that runs from just behind the operculum into the caudal peduncle.
A typical batch of fry is small, usually no more than 20 young, their growth is rapid if fed newly hatched Brine shrimp or sifted Daphnia as a supplement to microscopic fry food, pulverized, freeze dried Krill or freeze dried brine shrimp.
Gradually the young become both bolder and larger and venture further from their parents shell until they are eventually evicted and either take up residence underneath the shell of their parents or establish their own shell and surrounding territory and begin on their own family. Sexual maturity takes nine to ten months to achieve, at which point the mature males should have grown to 2 inches (5cm), the females being almost 0.5 inch (1.25cm) smaller.
Lamprologus ornatipinnis Poll 1949
Lamprologus ornatipinnis, female. Photo by Peter A. Lewis.
As with L. ocellatus this shell dwelling cichlid has been with the hobby for many years. As the specific name implies the beauty behind this fish lies in the "ornate fins" which are distinctively marked with a series of striations that vary from black to purple. The dorsal and caudal fins are especially attractively marked. While mature males may reach a total length of 2 inches (5cm) females are likely to be up to 0.5 inch (1.25cm) smaller. The female is also considerably plumper in the belly region and shows a distinct, metallic purple sheen in this region as she comes into breeding condition. Again the fish prefers a shell in the tank which it will proceed to bury and arrange to its liking prior to making use of the shell as both refuge and breeding shelter. Currently I house one male and five females in a 20-gallon (77-liter) aquarium decorated with a heavy growth of Java Moss, several shells and an arrangement of rocks and driftwood. Breeding is interesting to observe in that the male will await the call of one of the females whereupon he will enter her shell, if possible, to fertilize the newly deposited eggs only to reestablish his territory on a temporary basis around the entrance to the female's shell until such time as the fry appear out in the open around the mouth of the female's shell. At this point in time the male will promptly retire back to his own chosen shell and await further developments within his harem of females. Any attempt to introduce another male to this - colony of five females has always resulted in the intruder being banished to the corner of the tank from where he was removed before being harassed to the point of death. L. ornatipinnis also adopts the practice of shifting the gravel just outside the breeding shell to form a nursery pit or channel in which the young spend most of their time until they become fully mobile and independent of the protection afforded by the female.
Lamprologus signatus Poll 1952
Lamprologus signatus. Photo by Peter A. Lewis.
A species collected from the littoral zones of the Lake Tanganyika's Zambian shoreline in the vicinity of Cape Nundo and Cape Kabwe Ngosye. Males of this species, fully grown at 2 inches (5cm), are distinct in that their flanks are crossed by a series of 12 or 13 pairs of narrow, brown vertical bands that extend into both the dorsal and anal fins through the caudal peduncle into the caudal fin. The female does not possess any such markings and, in fact, when first collected the male and female were described as different species, the female more closely resembling L. ornatipinnis than L. signatus. A variable dimorphic trait is the presence of a distinct black spot or ocellus about midway along the dorsal of certain females but this does not hold true in all cases and may be an example of geographic variability. Although reported to be a monogamous cichlid I have had best results with L. signatus when maintained in a 20-gallon (77-liter) aquarium on a harem basis with one male serving the needs of four to five females and each female regarding several shells as their refuge rather than maintain just a single shell as their retreat. I think for a monogamous relationship to occur between a pair each must be allowed to select its own "mate" rather than merely putting a male and female together in the same tank.
Unique with L. signatus is the way both male and female will transfer the non-adhesive eggs and the wriggling fry, deposited initially deep inside an empty shell, between successive shells within the tank in much the same manner as certain of the substrate spawning cichlids will transfer wriggling fry between "nursery pits" excavated in the gravel. Spawns are small with 20-25 young from a single spawning being rare. More likely less than 15 young will result from each round of egg laying. Any attempt to house more than one male in an aquarium that provides insufficient territory or refuge will result in serious fights between the males which, while not resulting in death, will result in serious damage to the fins of the less fortunate combatant.
Neolamprologus boulengeri (Steindachner, 1909)
Lamprologus boulengeri. Photo by Peter A. Lewis.
This colorful shell dwelling species was in the original collection taken from the lake by Horn in 1908 and subsequently described by Steindachner. N. boulengeri has a confusing taxonomic history in that it has been knowa by the synonyms Julidochromis boulengeri,( Poll 1946), N. hecqui, (Boulenger, 1899) and L. kirivaithai (Meyer, 1986). It was left to Staeck in 1988 to set the record straight and confirm the name proposed by Steindachner in 1909.
Imported at regular intervals into the United States over the last ten years, N. boulengeri is yet another dwarf shelldweller that is attractively marked and that exists in an aquarium around a territory that has a shell as its focal point. Wild specimens for export are collected close to the town of Kigoma on the northeastern shores of Tanzania. Males attain a length of 2.5 inches (6.25 cm) while females remain only slightly smaller. In a tank containing both sexes the males can easily be identified since they are constantly displaying to the females and challenging other males. The dominant male is distinctly marked with a pattern of black blotches across light brown flanks. Two of these markings extend into the dorsal fin, the first at a point two to three spiny rays along this fin and the second at approximately the center of the dorsal. Although young of this species resemble closely N. hecqui and N. kungweensis it becomes very obvious as the species matures that indeed it is different. In addition to the characteristic blotch pattern across the flanks and into the dorsal N. boulengeri has a distinct orange-yellow border to the edges of both the dorsal and anal fins. The caudal, pectoral and pelvic fins are clear. The upper lip is a metallic blue and a thin blue line runs from the corner of the mouth, under the eye to end at the lower edge of the gill cover.
N. boulengeri like many of its cousins is a harem breeder with one male taking care of three to four females. One mature female may produce as many as 60 eggs during each spawning which can be as often as every six to eight weeks. N. boulengeri does not appear to be an obligatory shell-dweller since earthenware caves will also be used as spawning sites. The aquarium should be furnished with an ample layer of fine gravel or sand as the substratum so that any shells may easily and efficiently be positioned and buried to the individual requirements of each fish in the tank. Normally the male will be too large to fit completely into the shell such that he will be forced to eject his milt at the mouth of the shell, which he then vigorously fans into the interior of the shell.
Neolamprologus brevis (Boulenger, 1899)
Lamprologus brevis, gold spot. Photo by Peter A. Lewis.