In the aquarium trade, the most commonly available demonfish is a speckled-faced type - usually referred to as "jurupari"; sporting a pattern of bluish-white speckles on the cheek and operculum. In my experience, these fishes are usually very similar in appearance to those exported from Colombia and Guyana. They express a pattern of spots on the cheek and operculum, horizontal, wavy lines over the snout and a row or two of bright spots along the insertion of the dorsal fin. However, there are also fishes that find their way into the aquarium trade that exhibit significant variation in the pattern of cheek and operculum spots and lines on the snout.
One such "variation" was collected by Erik and Kathy Olson in the Rio Amazonas,
near Manuas in Brazil, in March 1999. They were collected as very small juveniles,
averaging 30 mm TL. Due to the size of the fish and the time of collection,
they were likely young of the year, having probably been produced at the beginning
of the 1999 rainy season which, in the Manuas region, starts near the end of
January. Later, in June, Erik and Kathy generously donated the eight fish to
my on-going study of demonfish. At the time I received the fish, it was not
possible to determine whether they would be speckled-faced, like S. leucosticta,
or like S. jurupari, and lack the cheek and operculum speckles.
The eight juveniles were placed in a 160 litre aquarium filled with unaltered, aged mains-water (pH 6.5, KH <1 DH) and filtered with an AquaClear™ 200 (with only the foam insert and a small amount of crushed coral substrate for pH buffering). The substratum was fine sand and a piece of water logged wood was added for cover. Illumination was provided by a single 25 watt, incandescent bulb. The temperature was maintained at, or around, 28 degrees C. Water quality was maintained with weekly 50-75% water changes and regular filter maintenance.
The little fish grew at the pace anticipated, compared to other species and
forms of Satanoperca, and readily accepted all foods offered: frozen
bloodworms, frozen Daphnia, flakes, pellets and finely chopped earthworms.
Within several months, the young fish began to exhibit speckles on the cheek
and operculum. Admittedly, at this point I pre-maturely concluded that these
were probably going to be delayed mouth-brooders, as all of the popular accounts
would have suggested. Over the last several years, and looking back at popular
accounts accompanied by photographic evidence of the beasts in question, the
speckled-faced demonfish have invariably proven to be delayed mouth-brooders.
While at one time, all of the demonfish were considered to be delayed mouth-brooders,
S. jurupari, S. pappaterra and S. daemon are not.
However, reproductive maturity for these juveniles was still a considerable
time away and so I focused on the task of getting them there.
The eight fish continued to do well under the care regime described above.
They did, however, out-grow the modest housing arrangements afforded by the
160 litre aquarium and were sub-sequently moved, in March 2000, to a relatively
spacious 360 litre aquarium, set-up and maintained in much the same way as the
160 litre aquarium. The exceptions were; the volume of the water changes was
increased to 75-80% weekly and they now shared their accommodations with six
The fish were moderately social, seemingly willing, or able, to tolerate the close company of conspecifics. Save the occasional torn fin suffered by subordinate animals, no major aggression or damage was observed.
By June 2000, the largest of the eight fish was approximately 160 mm TL, and did, then, seem a little boisterous, particularly in terms of chasing, for the six co-housed Biotodoma cupido. The B. cupido were removed and the eight demonfish were given the 360 litre aquarium to themselves. Very quickly a hierarchy was established; the larger fish occupied the more dominant positions and the smaller fish were relegated to more subordinate standings. The hierarchy certainly complicated the task of evenly distributing the food. Ensuring an equal share for all was very difficult which resulted in an ever-increasing discrepancy in size among the eight fish.
In August, I decided to reduce the group of eight fish down to four - I took out the very largest individual and several of the smaller, stunted, fish. The resulting four fish were very close in size, three were almost the same size and one was a little larger. I was not concerned about the sex ratio of the new group of four fish - I was still relatively confident that both sexes were represented.
With only four modest sized demonfish in a 360 litre aquarium, maintaining water quality was relatively simple - with the large, frequent water changes pH remained stable at 6.5 and the nitrate never exceeded 5-10 mg/l. Within weeks of removing the other four fish, one of the smaller fish began chasing and displaying to the larger. In Colombian "leucosticta", I've observed females initiating courtship, but in this case the smaller fish was decidedly slimmer in abdominal profile than the object of its attention. Based on less than indisputable evidence, abdomen profiles and soft dorsal extensions, I concluded that I had reduced the population down to three males and one female.
The male was constantly moving from one end of the aquarium to the other; at one end he was trying to entice the female, with branchiostegal ray flaring and lateral displays, into staying, and at the other, trying to persuade, with chasing and caudal nipping, the two males into leaving. The 360 litre aquarium was 120 cm long and 45 cm wide, which was seemingly able to provide enough space for the male and female to begin their nuptials without serious harm befalling their obviously unappreciated neighbours. Within a few days it was clear the female had accepted the advances of the male and was returning his displays in like fashion. The courtship behaviour consisted of reciprocal lateral displays, branchiostegal ray flaring and mock digging. The mock digging was where one fish at a time would plunge their mouth into the sand and then shake their head as the sand is expelled, both from the mouth and opercula. This behaviour persisted for several days when at last, I inadvertently observed both the male and female preparing a spawning site. The site they had chosen was a small piece of white PVC pipe that was being used to plug a hole I had previously drilled in the bottom of the aquarium. Apparently, the smooth, clean surface, hidden under a piece of water logged wood and clearly out of "photographic view" was the most suitable site for their needs.
The site preparation only lasted a few hours at which time the female began "dry runs" over the top of the PVC pipe. The male was attentive, but did leave frequently to chase the other two males to the far end of the aquarium. Unfortunately, the two males were not easily deterred by the paired male, despite the enthusiasm with which they were chased. With ragged caudal fins and missing scales, the two males ventured into the spawning territory of the pair every time the paired male returned to the female - only to be chased away again.
After about 10 to 15 minutes of "dry runs", the female began to deposit light brown eggs on the top of the PVC pipe. Completely unexpectedly, she immediately circled back to the PVC pipe and picked the eggs up in her mouth! This was the first speckled-faced demonfish, to the best of my knowledge, to exhibit immediate mouth-brooding behaviour.
During the spawning, it was difficult to ascertain the sequence, in terms of egg deposition and fertilization, due in large part to the distraction caused by the interloping males. However, between distractions the female would lay a row of 10 to 15, non-adhesive eggs, then circle back and immediately pick them up. The male would then pass over the site pressing his spawning tube along its surface and deposit sperm. The female would then return and pick the sperm up in her mouth.
After numerous runs, the female seemed to be having some difficulty in holding all of the eggs in her mouth, evidenced by the fact that with each new pick-up, eggs would fall from her opercula. This only served to attract the extra males, not likely they were going to resist the temptation of abandoned eggs on the sand. With the extra males trying to feed on the dropped eggs, and the male chasing them away at every opportunity, the spawning sequence lasted for almost an hour. Despite all the activity involving the three males, the female seemed rather unconcerned, remaining focused primarily on the task on laying and picking up eggs.
Several hours after spawning, the paired male seemed no longer interested in the female; in fact, he began to chase her. While it seemed that the female was just trying to remain out of contention in the pecking order, she was unwillingly included by all three males - according to the re-established hierarchy. The spawning male became the dominant animal in the aquarium and the two other males were ranked according to size, as before. With frequent attention from the males, the female only held her brood for two days. She then resumed feeding, and re-established her position in the hierarchy.
About three weeks later, the female and a male paired up. It was not clear, if the male in this pairing was the same one the female had paired with in the first observed spawning. This time, however, a little more site preparation was done. A large pit was excavated beside the previously used PVC pipe. They spawned on the PVC pipe with all the previously described attention from the two unpaired males. Once again, the female only held the brood for two days.
Several weeks later they spawned again. This time I was relatively certain that the male involved was the one from the first spawning. However, during the spawning sequence, I removed the two unpaired males to another aquarium. This action seemed to have no effect on the enthusiasm with which the two paired fish carried out their task. By removing the two extra males and the associated distractions, I thought the female might be able to hold the brood to term. Still, once the spawning was completed, the paired male began to chase the brooding female, likely as a result of not having target-fish present to vent his aggression towards. Therefore, I removed the spawning male and placed him in the company of his two rival con-specifics. This time, the female held the brood for three days.
At this time, I decided to use the 360 litre aquarium for some other cichlids and moved the female to the 280 litre aquarium housing the three males. The 280 litre aquarium was set-up like the 360 litre aquarium, except two air-driven box filters were used in place of the AquaClear™ 300. Within two weeks they spawned again, although this time after they had finished spawning, the group of four fish seemed to get along just fine. The female was left in relative peace and quiet. Admittedly, with each passing day I expected to find the female front and centre at feeding time, rather than holding back despite the obvious temptation, but she held the brood for nine days. Realising she may not release fry in the close company of three decidedly, non-parental males, I decided to move the female to her own, 160 litre, brooding aquarium. The brooding aquarium was set-up in similar fashion to the original 160 litre aquarium, with the exception that an air-driven box filter was used instead of an AquaClear™ 200.
The water level in the 280 litre aquarium was lowered to about 25% of its full volume and the female was carefully coaxed into a clear plastic container. While still underwater, the lid to the container was screwed in place and then lifted out of the aquarium. At this point the female, obviously realising her situation, thrashed wildly and in the process released the fry into the container. The container was quickly lowered into the brooding aquarium where the female, and the fry, were released. Within several minutes, the female had retrieved all the fry.
The next day, the fry accepted newly hatched Artemia as their first meal. Over the next several days the female gradually released the fry more frequently, and for longer periods. Unlike the Colombian "leucosticta" females I've observed in the past, this female primarily released the fry by expelling them from the opercula, as opposed to from the mouth. Despite the large number of eggs produced at the time of spawning, probably around two hundred, the brood consisted of about 35 fry.
For about three weeks, the female took the fry into her mouth at any perceived threat. When alerted, the female quickly dropped to the sandy bottom, opened her mouth and moved slowly backwards while the fry rushed into her mouth. The fry were not be re-released until the female felt quite satisfied the threat no longer posed any danger to her brood. As the fry grew, they were no longer taken into the female's mouth at night; instead they were herded into a tight group over a piece of water logged wood and remained positioned under the female's head. By the time the fry were four weeks old, the female was no longer able to accommodate all of them in her mouth. This seemed to stress the female, evidenced by the dark, barred colour pattern and flighty swimming behaviour. This behaviour prompted the decision to remove the female from the brooding aquarium and place her back with the males. The fry seemed unconcerned that "mom" was gone, and began to more thoroughly disperse throughout the aquarium.
The fry seemed to recognize frozen bloodworms, since these were fed to the female in the brooding aquarium, and readily accepted them chopped. Also added to the diet were live Daphnia and crushed flakes. At four and a half weeks old, the fry were already quite focused on the substratum, sifting a few sand grains at a time in a constant search for something edible.
There is significant variation in the colour pattern of the various "forms"
or "geographical morphs" of speckled-faced demonfish imported by the ornamental
fish trade and in those collected by adventuresome individuals. It also appears
there is some variation in the reproductive modality in this group of leucosticta-like
demonfish. The extent of variation seems hardly surprising given the numerous
localities from which speckled-faced demonfish have been collected, particularly,
outside the range described for S. leucosticta. In Mesonauta
and Geophagus (sensu Kullander), the various "forms" or "geographical
morphs" were, in some cases, described as new species. If the situation proves
to be the same for Satanoperca, then its more than likely, that at
some point in the future, we'll be learning a bunch of new names for the speckled-faced
demonfish we currently, conveniently lump as "leucosticta".
Despite the relative "commonness" of Satanoperca leucosticta, hobbyists
with an interest in these fishes may well be advised not to casually pass by
what they think is yet another tank of "leucosticta"; the shy fishes in the
back of the tank might just well be speckles of a different kind. □