Among the Nonh American cichlids, which I covered in Part Three of this series, there are cichlids with specialized adaptations which allow them to sift food items from the substrate. As I said there, the members of the Thorichthys section of 'Cichlasoma', and some of the members of the Amphilophus section, have elongated snouts which point downward and have the mouth positioned terminally, and have eyes which are set back on the head away from the mouth. These adaptations allow these fish to push the mouth down deeply into the substrate without endangering their fragile eyes.
In South America there are cichlids which have evolved even fluther specialization for sifting for food. These cichlids are the Geophagines, which literally means the "Earth-eaters," and these fish are the subject of this part of the series.
Of course, Geophagines do not literally eat the earth, they merely sift through it. This latter, however, they do with great efficiency. Besides adaptations to the facial structure to allow for rooting about in the substrate, Geophagines have a unique gill morphology that allows them to easily separate inedible sand from food. From a single mouthful of mixed sand and food, the edible portion is ingested while the grit is spit back out of the mouth or passed out behind the gill covers.
Geophagines are also interesting subjects due to their reproductive strategies. There are a wide variety of reproductive strategies found within the group as a whole, including biparental substrate-spawning and delayed mouthbrooding (both of which are found in the Cichlasomines, as discussed in the first three parts of the series); polygynous, immediate mouthbrooding; harem polygynous, substrate-spawning; and apparently even the extraordinarily rare, monogamous, immediate mouthbrooding.
Further, whereas reproductive strategies are generally uniform within a given genus, a range of strategies are present within some individual Geophagine genera.
The Genera
Geophagus Heckel 1840
Like several genera discussed in the earlier parts of this series, the genus Geophagus has recently been restricted to exclude many of the species that once went by that name. The species that remain may be thought of by aquarists as the surinamensoids, as the few members of the restricted Geophagus that are regularly found in the hobby are almost uniformly referred to as Geophagus surinamensis. According to the current understanding of these species, however, it is unlikely that the true G. surinamensis has ever been found in the hobby or that it will be commercially collected in the near future, due to the location and small extent of its natural range. The species referred to in the hobby as G. surinamensis are, in reality, other species of the restricted Geophagus, most commonly G. brachybranchus, G. megasema, and G. proximus.1 These fish can easily be distinguished by markings on the face, flank, and caudal fins.
The Geophagus species commonly found in the hobby grow quite large (up to a foot, total length), but some of the less well-known, and recently described species apparently stay quite a bit smaller (e.g. up to 6" for G. taeniopareius, and less than 4.5" for G. grammepareius). Geophagus is known to include substrate spawners (such as the recently described G. argyrostictus), delayed mouthbrooders (e.g. G. brachybranchus), and advanced mouthbrooders (e.g. G. megasema). There are probably at least fifteen species of Geophagus, although less than a dozen have been described.
Satanoperca Gunther 1862
One of the best known sifters in the aquarium hobby is the fish usually referred to as "Geophagus jurupari". According to current understanding, however, this fish and its close relatives really belong in the genus Satanoperea. Further, the hobby "Jurupari," which possesses white spots on its face and gill covers, is really S. leucosticta (the species name referring to the white spots). The true S. jurupari lacks any sort of spotting on its head. These species are delayed mouth-brooders.
Closely related to these two species are S. pappaterra, and apparently several other species which either need to be described or need to be matched with names which have previously been treated as junior synonyms for S. jurupari. These include a species which resembles S. pappaterra and hails from Peru2, a species which resembles S. leucosticto but lacks spots on the gill covers3, a species found in Peru which resembles S. jurupari but has a shorter snout4, and a comparatively small Satanoperco species which apparently is an immediate mouthbrooder.5 Due to its origin, it has been speculated that this last fish may match with S. mapiritensis.6
Satanoperca also contains a complex of sifters with large spots on their sides and trailers on the last several rays of their dorsal fins. The best known of these species is S. daemon, which possesses two large spots on its side and a well-ocellated spot on its caudal peduncle. S. daemon is a substrate spawner with a twist. It buries its eggs under two inches of sand, digs them up when they hatch only to bury the wrigglers again, and finally digs up the fry when they are ready to be free-swimming.
The other spotted Satanoperca species (S. lilith, which has a single side spot located high up on the side but otherwise resembles S. daemon, and S. acuticeps, which has three side spots and no ocellus on the caudal spot) have not been spawned in captivity.
Satanoperca species tend to grow slowly, but most can get quite large -- up to a foot in length.
Hump-head Eartheaters
The fish I am referring to here as hump-head eartheaters, like the species of Satanoperca above, were regarded as belonging to Geophagus until that genus was restricted recently. Unlike the Satanoperca species, however, this group of species is of "orphaned," that is, temporarily lacking a proper generic placement.
The best known species of this group in the aquarium hobby is 'Geophagus' steindachneri, the "Red-Hump Eartheater." This fish has gone by many names in the aquarium hobby, including G. magdalenae, G. hondae (both invalid junior synonyms for G. steindachneri) and G. pellegrini. 'G.' pellegrin, properly refers to a different species in the bump-head group, and the other described species in this complex is 'G.' crassilabris.
These fish come from the northern flowing rivers of Columbia and from Panama. All are immediate mouthbrooders, and the males like so many African rift-lake cichlids, have no parental role to play once fertilization has taken place.
Brasiliensoids
Another group of orphaned species formerly belonging to Geophagus are the brasiliensoids. Currently there is only one recognised species in this group, 'Geophagus' brasiliensis, which is ostensibly a common aquarium fish. However, once a modern review of these fish takes place I believe that a number of separate species will be recognized within this group.
Brasiliensoids known in the hobby are biparental, substrate spawners and are notably more aggressive than most other Geophagines.
Wayne Leibel has speculated that the brasiliensoids are closely related to the rhabdotus complex species of Gymnogeophagus, but I think that the unique skeletal characteristics of that genus (see below) preclude a merger of these species and those at the generic level.
Gymnogeophagus Ribeiro 1918
The genus name Gymnogeophagus means, literally, naked earth-eater. The prefix gymno (naked) refers to the fact that these fish lack scales on their cheeks and was the primary character used to establish the genus in 1918. Since then many ichthyologists have considered this character as too weak to justify a genus and counted these species as belonging to Geophagus. In 1976, however, Gosse reexamined these fish and discovered that they possessed unique skeletal structures at the ftont of the dorsal fin including an 'antrorse spine' that is not found in any other new world cichlid. While the genus Gymnogeophagus contains distinct groups within it and may at some point be split into distinct genera or subgenera, these skeletal features ensure that these species will always be set apart from all other cichlids.
The type species of Gymnogeophagus is Gg. balzanii, an unmistakable cichlid with a steep cranial profile, especially in mature males in which the face may rise straight up from the mouth to the top of the head, and nearly unique vertical stripes on the flanks which form double "pin stripes" on the lower side. (This latter characteristic is shared with a Biotodoma species. See below.) Gg. balzanii is a harem polygynous, delayed maternal mouthbrooder. That is to say, a single male holds a breeding territory in which several females care for the eggs and fry and the females carry the fry in their mouths, though not the eggs.
Quite unlike Gg. balzanii are a group of species regarded as belonging to Gymnogeophagus, but resembling 'G.' brasiliensis more in overall shape and coloration. The best known species in this complex is Gg. rhabdotus, although many fish sold under this name are not this fish at all. As I have shown elsewhere7, many of the fish sold locally under this name are really brasiliensoids as they lack the unique skeletal features of Gymnogeophagus. Paul Loiselle has written widely about Gg. rhabdotus under the name Gg. australis8, but it is now known that that species is a member of the gpnnogenys complex9 (see below).
Gg. rhabdotus is known to be a simple substratum spawner. The other two members of the rhabdotus complex are Gg. meridionalis and Gg. setequedas.
Finally, the remainder of the fish in Gymnogeophagus belong to the gwnnogenys complex. Like Gg. rhabdotus, many fish sold as Gg. gymnogenys really were (are) not. Finally, however, the true Gg. gymnogenys appears to be getting a hold in the hobby, so it is possible to get the real thing these days. Gg. gymnogenys is an elongated sifter and adult males are unmistakable. They posses red unpaired fins, a red patch on the gill covers, and unique black markings including a "collar" running from behind the gill covers up to the back just in front of the dorsal fin and a "mask" which runs up from the lower jaws to the eyes then angles forward around to the front of the face.
Gg. gymnogenys, like Gg. balzanii, is a polygynous, delayed, maternal mouthbrooder. The other members of the gymnogenys complex are Gg. labiatus, Gg. lacustris, and, quite notably, Gg. australis which, although known widely by name in the hobby, is unlikely to have ever been kept in aquaria.
Biotodoma Eigeomann & Kennedy 1903
The genus name Biotodoma means living-home and refers to Eigenniann & Kennedy's mistaken belief that these cichlids are mouthbrooders. In fact, however, Biotodoma species are substrate spawners and only move their fry from place to place in their mouths, in the manner of other substrate spawners.
The type species of Biotodoma is B. cupido and is sympatric with the other nominal species of the genus, B. wavrini. Both of these species are quite unimpressive as juveniles, but adults possess wonderful rose and coppery colors and blue lines (males) or spots (females) on their faces.
A third, and as yet undescribed, species of Biotodoma has found its way into the aquarium hobby. B. sp. "Red Fin Tocantins" is a strikingly colored fish with a lyrate caudal fin and double "pin-stripe" lines on their flanks. They can be sexed as the other species in the genus.
Retroculus Eigenmann & Bray 1894
The species of Retroculus are some of the most highly specialized cichlids in the world. Not only are they Geophagines (with all the associated adaptations for sifting), but they are also specialized rapids dwellers with the elongated bodies and reduced swim-bladders that are favored in fast flowing aquatic environments.
Three species of Retroculus are recognized, R. lapidifer, R. septentrionalis, and R. xinguensis. Leibel reports that, while R. lapidifer comes from moderately cool and highly oxygenated waters in the wild, they are hardy fish in more typical tropical aquariums.10
Cardwell reports that R. xinguensis is found over a sand substrate and will bury itself quickly in the sand to avoid perceived dangers (such as collectors with cast nets).
Acarichthys Eigenmann 1912
Acarichthys is a monotypic genus with the single species being A. heckelii. This species is not a true Geophagine as it lacks all of the specialized gill morphology that characterizes that group. I have included it here, however, as it resembles the true Geophagines in most other respects and "fits" well in an article about them. A. heckelii is most definitely a sifting species and Steindachner described it as Geophagus thayeri in 1875. (This was over 25 years after the species was first described, however, so G. thayeri is an invalid junior synonym.)
A. heckeiii do differ from all the true Geophagines (and all other cichlids for that matter) in the manner of their breeding, however. They are substratum spawners, but the females dig extensive tunnel networks in the substrate and actively court the males from these tunnels and the surrounding territory.
Guianacara Kullander & Nijssen 1989
The species of Guianacara are also not true Geophagines but, like Acarichthys, resemble them in most ways. They also have many similarities to Aequidens species and other Acaras so Leibel often includes them in articles on Acaras. In fact, Guianacara geayi was originally described as Acara geayi and known for a long time as Aequidens geayi.
Kullander briefly and provisionally assigned this species to Acarichthys (apparently, mostly because he didn't know what else to do with it) but, after further research, he and Nijssen decided to create a genus just for geayi and its sister species, which they described at the same time.
From spawning reports and photographs it appears that more than one species of Guianacara has been found in the hobby under the name geayi, although the true G. geayi does not appear to have been among them. I have found both G. owroewefi and G. sphenozona in store tanks in the midwest. These fish, like most species in the genus, are distinguished by subtle differences in the black markings.
The easily distinguished G. sp. "Red Cheek" has also recently found its way into the hobby and been spawned by dedicated aquarists. All Guianacara species look a bit like overgrown, golden rams with black markings.
Papiliochromis Kullander 1977
Papiliochromis ramerezi, the popular Ram of the aquarium hobby, is a true Geophagine, despite its small size. This fact is reflected in the other generic name sometimes applied to this fish, Microgeophagus. Papiliochromis, for its part, means (roughly) "butterfly cichlid" and refers to the other common name for Rams. (According to the somewhat twisted rules of zoological nomenclature, Microgeophagus is currently the proper generic name for this species, although it was never properly erected and, I'm confident, will eventually be discarded in favor of Papiliochromis.)
A second species in this genus was recently recognised. The Bolivian Ram, P. altispinosa, is a higher-bodied fish with a lyrate caudal fin.
Apistogramma Regan 1913
Also among the true Geophagines are the species of Apistogramma. This genus includes the smallest of all new world cichlids and includes at least sixty species, many of which remain to be described. There are at least a half-dozen groups or complexes within Apistogramma, although not all species fall neatly into one of the divisions.
Apistogramma species differ from most other Geophagines in a number of respects, mostly having to do with reproduction. They are also more elongate than most Geophagines.
Apistogramma species are harem-polygynous, cave-spawning cichlids. A male will guard a territory in which several females breed and the care of the eggs and fry is exclusively the female's domain.
Like most cave-spawning cichlids, territorial males and females are easily distinguished. Territorial males are larger, more colorful, and have more impressive finnage. Outside of spawning, females are generally light grayish or tannish with muted black markings. When spawning or spawn tending, on the other hand, females acquire a bright golden-yellow base color with dark black markings.
Quite interestingly, there are non-territorial males which still manage to reproduce. These males look remarkably like females, both to aqurists and to territorial Apistogramma males. By fooling the territorial male, these "sneaker males" are able to slip into the caves of ready females within the territorial male's dominion and fertilize some or all of the eggs before the dominant male has the chance to.
"Sneaker males" only occur in situations where some males are unable to establish territories of their own and will become territorial males themselves, with the accompanying impressive colors and finnage, if a space opens up in the region's hierarchy.
Apistograminoides Mcinken 1965
The final genus of Geophagine is the monotypic Apistogrammoides. As implied by the name, Apistogrammoides is closely related to Apistogramma. It differs primarily by the number of hard rays in the anal fin. In Apistogramma, three to four rays are typical. In Apistogrammoides, the range is seven to nine.
The single species in Apistogrammoides is A. pucallpaensis, which is named for its collecting site of Pucaflpa, Peru. A. pucalipaensis can be treated by aquarists as they would species of Apistogramma.
Keeping
Geophagines span the spectrum of cichlid difficulty, from hardy, easily kept and bred species ideal for beginners, to demanding and difficult fish that are more challenging than discus. In general, all members of a genus can be kept in the same approximate conditions, but for breeding it may be necessary to know the precise species that one is dealing with (see Breeding below).
Water Parameters
Geophagines can be found in all of the water types in South America (see Part One of this series). Species of Guianacara (which come from the rivers of the Guianan shield), the Hump-head Earth-eaters (from Panama and the northern flowing rivers of Columbia), and the Brasiliensoids (from the coastal rivers of Brazil) all hail from moderately hard, and relatively neutral waters. These fish can be comfortably kept and spawned in a wide range of pH and hardness values, as long as extremes are avoided.
Most other Geophagines come from more cosmopolitan genera, so species specific information is needed for determining ideal water conditions for them. If this information is not available, however, they can be kept in soft to moderately hard (DH 5-10), slightly acid to neutral (pH 6-7) water without trouble. For breeding, however, some species (such as daemon complex of Satanoperca and many, though certainly not all, Apistogramma) need water that is very soft (nearly unmeasurable hardness) and acid (pH around 4). These conditions can stress members of other species, however, so it is imperative that the aquarist know the breeding requirements of the species that he or she is dealing with before attempting to provide these sorts of extreme conditions.
Interestingly, it has been shown that some Geophagines that have evolved to handle low pH levels in nature actually grow faster in water with a more neutral pH.11 This is apparently because they only encounter low pH during the dry season as water levels fall and acids become concentrated. A reduced growth rate during the dry season means that these fish require less food to survive during these lean times. When the rains increase again and food becomes more abundant (and the pH rises), the cichlids' growth accelerates.
Almost all Geophagines need warm water in the range of 75-80°F to prosper. Some species, like those of Biotodoma, only grow well in even warmer temperatures -- up to 85°F. The notable exceptions to this rule are the brasiliensoids which will live and breed in the home aquarium at 70°F. Also, species of Gymnogeophagus may be kept around 70°F, although they generally cannot be induced to spawn at this temperature.
All Geophagines do best in clean water and regular partial water changes are essential to maintaining healthy fish. Especially vulnerable to poor water quality are species of Satanoperca, Geophagus, and Biotodoma.
Most Geophagines come from relatively calm waters. The exceptions here are the Hump-head Earth-eaters which come from flowing waters, and species of Retroculus which come from swifty flowing areas including rapids.
Tank Set-Up
Geophagines are, first and foremost, sifters. They will spend most of their time during the lighted hours of the day taking up mouthfuls of sand and attempting to separate out any food particles that they can find. For this reason, the choice of substrate for a sifter tank should not be taken lightly. Large pebbles or gravel may become lodged in a Geophagine's mouth and cause injury or death. Sharp gravel is also, quite obviously, also a poor choice. A lack of substrate will not injure these cichlids but will frustrate their natural instincts and deprive the keeper of witnessing their natural behavior.
The best choice for substrate in a Geophagine tank is rounded silica sand. This inert sand will pose no threat to the fish, will not effect water parameters, and has a natural look to it. Of course, other choices of coarse sand or fine gravel may also prove adequate. Obviously, these fine substrates exclude the use of undergravel filtration.
Large rocks, driftwood, and submerged roots make effective territorial boundaries and spawning sites while retaining a natural look to the aquarium. Appropriately sized flower pots and pieces of PVC piping make practical hiding places and spawning caves if appearance is not a major concern.
The dwarf Geophagines will do quite well in planted tanks and will pose no treat to the plants, but larger species may uproot or tear apart live plants. This is not true for all large Geophagines, however, and sturdy, well rooted, potted plants are compatible with species of Geophagus, Satanoperea, and Biotodoma, and with Gymnogeophagus balzanii.
Food
Geophagines, despite their natural habits, will quickly learn to take food from the surface of the water in captivity. However, many species remain clumsy at this unnatural feeding situation and, if kept with more efficient surface feeders, should be given sinking foods to ensure that they receive their fair share.
Prepared foods can make up the bulk of the sifter's diet for keeping. These should be supplemented with frozen and/or live foods such as blood worms, brine shrimp, and glass worms. For breeding purposes, the balance should shift to frozen and live foods for the bulk of the diet and feedings should be heavy (and accompanied by many partial water changes to maintain water quality). The dwarf Geophagines may also be conditioned on baby brine shrimp.
Greens are unlikely to be eaten by most sifters, although peas may be accepted. Feeder fish are likely to grow and prosper in a Geophagine tank, as these fish are quite awkward piscivors. They will, however, sift hiding fry from the substrate if they get the chance.
Tank Mates
Most Geophagines are peaceful cichlids and make good community tank residents. The most aggressive Geophagines are the brasiliensoids, which can hold their own with all but the most aggressive Cichlasomines. The recommendations for tank mates listed below do not necessarily work well for brasiliensoids, which should be kept with the same types of tank mates as large Acaras (see Part One). At the other end of the scale are Satanoperca species which can be housed with Angels and small Tetras without problem. As long as a Tetra is fast enough to avoid an Angelfish, it is more than quick enough to escape the attentions of Satanoperca.
Despite their peaceful nature, most sifters are able to hold their own with somewhat more aggressive cichlids, but do their best if kept with other peaceful fish. Good choices for tank mates for most large Geophagines include all Acaras except Green Terrors (as discussed in Part One of this series), High-bodied South American Cichlasoniines (covered in Part Two of this series), Tetras and other peaceful characins, loracariids of all sizes, carichthyids (Corydoras and related genera), and small pimelodids. Note, however, that while all of these fish are compatible with large Geophagines, they are not all compatible with one another.
Dwarf Geophagines can be kept with dwarf Acaras and the remaining dwarf South American cichlids (which will be covered in the final part of this series), the more peaceful (and non-piscivorous) High-bodied South American Cichlasomines (e.g. Angels, Discus, and Festivums), Tetras, loracariids, and callichthyids.
Dither fish, such as Tetras, are highly recommended for tanks containing dwarf Geophagines, and may also help to calm large Geophagines and encourage breeding.
Breeding
Geophagines show a diversity of breeding strategies and behaviors unmatched in any other group of New World cichlids. Further, as mentioned above, breeding strategies and behaviors may vary from species to species within a genus. Finally, the species within a genus may come from different water types. For these reasons it is important to know the particular species one is dealing with in order to be prepared to spawn them.
The hardy brasiliensoids, like many popular Cichlasomines, are easily spawned and make good beginners fish. The recently popular 'G.' steindachneri likewise makes a good beginners cichlid. It is easily kept and will spawn given a diet of only prepared foods. In fact, perhaps the only way to prevent a pair of these cichlids from spawning, short of separating the male and the female, is to reduce the tank temperature below 70°F. The fry of 'G.' steindachneri are large enough to take finely crushed flake food as a first meal, although they will do better on a diet of newly hatched brine shrimp.
At the other end of the scale, only one species of the daemon complex of Satanoperca has ever been successfully spawned in captivity (S. daemon itself) and this only once. The cichlid enthusiast looking for a breeding challenge should move right past the comparatively easy Discus to the members of the daemon complex, but only if he or she is truly prepared. These fish do NOT make good beginners cichlids. Not only are they extremely difficult to spawn, but many very experienced aquarists have trouble just maintaining them in captivity.
Other Geophagines which are challenging to breed include Acarichthys heckelii, the other Satanoperca species (the juruparoids), Biotodoma species, and many species of Apistogramma. One of the keys to spawning many of these species is patience. Many of the large Geophagines grow quite slowly and are not mature until they are a few years old. Dwarf species, on the other hand, mature quite rapidly (they are essentially annual fish) and may spawn at only two months post-hatching.
Another factor that makes spawning many Geophagines difficult is sexing the adult fish. As is the general rule with cichlids, when parental duties are shared equally by both parents, the fish as essentially sexually isomorphic. Species of Geophagus and Satanoperca, and Acarichthys heckelii are particularly hard to sex. Biotodoma species can be sexed by their facial markings as noted under the description of that genus. Gymnogeophagus, Guianacara, Papiliochromis, and the brasiliensoids can be sexed by size differences (males are larger) and cranial profile (males have steeper faces). Territorial males of Apistogramma can be recognized at a glance, but subdominant males may be difficult to distinguish from females (see Apistogramma, above). Finally, Hump-head Earth-eaters can be sexed easily by the humps of the males and by males' more impressive coloration.
Blackwater Geophagine species are especially difficult to spawn as they need very soft water in order for their eggs to be fertilized (in hard water the eggs close up before the sperm can penetrate) and a low pH to trigger spawning and allow for a reasonable sex ratio in the fry.
Finally, because most Geophagines are so peaceful, a crowded tank or aggressive take mates will inhibit spawning behavior.
Most Geophagines lay their eggs on flat surfaces, such as smooth rocks, although the immediate mouthbrooders are less likely to be fussy about their spawning site than delayed mouthbrooders or substrate spawners. As noted above, S. daemon lays its eggs in a depression it digs in the substrate. Some Geophagines, notably species of Satanoperca, will cover their eggs after spawning, so do not be alarmed if sand sits where the eggs "should" be.
Apistogramma and Guinacara species and Acarichthys heckelii are sheltered spawners and appropriate cave or tunnel-like areas should be provided. For A. heckelii it may help to fill the intended spawning site with sand and allow the female to excavate it herself.
In all, Geophagines exemplify the degree of diversity that may be found within a single cichlid lineage, especially in terms of breeding behaviors. The diversity of New World cichlids, however, is much broader than that of any one lineage. Some of the most unusual and interesting New World cichlids are yet to be covered. For those, see the next and final installment of this series, in the November/December Aqua News!
1 Axelrods Atlas, for example, shows G. tacniopareius (p. 355, picture 5), G. brachybranchus (p. 355, pictures 6-8), G. proxixnus (p. 356, picture 1), and G. altifrons (p. 356, picture 2), all labeled as G. surinainensis.
2 Leibel, 1990, p. 17.
3 Ibid.
4 Schlesff, 1994, pers. comm.
5 ???, 1994, pers. comm.
6 Leibel, 1994, pers. comm.
7 Hougen, 1993
8 1980a, 1980b, 1981, 1995.
9 According to systematists currently working with Gynmogeophagus. See Reis, et al., 1992, p. 271.
10 1989, p. 24.
11 See Newman.
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