The two species of Hypselecara,
as presently defined, are easily
differentiated. The overall appearance
of H. temporalis is almost
"square" due to its steep profile,
while H. coryphaenoides is
more elongate with a gradually elevated
profile. There are also color differences
between the species. The form of
H. temporalis common in the
hobby is a green and red-wine fish
with a darker lateral blotch centered
below the lateral line; H. coryphaenoides
is dark-brown to black with a blotch
centered above the lateral line
and extending into the base of the
soft dorsal fin. Unfortunately,
two factors complicate identification
efforts. First, markings in H.
temporalis tend to be quite
variable depending on geographical
origin; second, H. coryphaenoides
is subject to great changes in color
and pattern depending upon "mood."
As a helpful guideline, wild H.
temporalis are usually collected
in Peru, while H. coryphaenoides
is most often taken in Brazil.
As H. coryphaenoides is
comparatively rare in the trade,
the chocolate cichlid most likely
to be encountered is H. temporalis.
Nevertheless H. coryphaenoides
does not appear to be rare in the
wild; in habitats in which we found
the species (described below), it
was easily collected. However, despite
the presence of other rarely seen
(in the trade) cichlid species (i.e.,
Satanoperca acuticeps) in
exports from Manaus (Brazil), H.
coryphaenoides was absent. Whether
this reflected a seasonal phenomenon
or just low demand was not investigated.
In January 1996, the Vancouver Aquarium provided resources for me to participate in a two-week aquarist expedition to the Rio Negro and Rio Branco in Amazonas, Brazil. The trip was set up to support Project Piaba, an ornamental fisheries conservation project, while also allowing participants the freedom to pursue individual interests. Representing the Aquarium, I was expected to assimilate as much about the project as possible; however, all my free time was spent studying and collecting cichlids.
The expedition was based aboard the "Cassiquiari," a spacious, 65-ft boat with ample room for the fifteen participants in the trip. The expedition took us from our starting point in Manaus on the lower Rio Negro upriver to Barcelos, then back down the Rio Negro to the Rio Branco, which allowed us a few days to explore a "whitewater" river. The trip concluded in Manaus with a brief excursion to the "meeting of the waters" where the blackwater Rio Negro flows into the whitewater Rio Amazon, plus an opportunity to visit two tropical fish exporters.
Most aquarists with plans to take fishes back to the U.S. or Canada had target-species in mind. Although I tried to remain flexible as collecting in the field is rarely as predictable as buying fish in an aquarium store I hoped to collect some of the cichlids less frequently seen in the hobby.
A brief stop at a floating hotel along the Rio Cueiras, a blackwater tributary of the lower Rio Negro, provided the first opportunity to collect fish the first night out enroute to Barcelos. The hotel was positioned near a cleared section of the gently sloping riverbank and was floated on large tree trunks. By lying on the perimeter walkway and bending over the edge, I was able to collect with a dipnet from the submerged tree trunks.
Abundant in very shallow water
were armored catfish of the genus
Ancistrus and palaemonid shrimp,
as well as juvenile H. coryphaenoides.
Both the catfish and the chocolate
cichlids were using small cavities
or rotted holes in the well-worn
trunks for cover. Within an hour
with a dipnet in one hand and
a flashlight in the other I managed
to collect small samples of both
species. The chocolate cichlids
I magnanimously distributed among
other interested aquarists on the
trip. Though I thought H. coryphaenoides
would be a good species to take
back to Vancouver (the chocolate
cichlid usually available there
is commercially produced H. temporalis),
I figured that there would be other
opportunities to collect them before
the end of the trip. Unfortunately,
this was not to be the case!
Late in the trip during our return
to Manaus, we stopped one afternoon
on an island in the Rio Negro just
south of its confluence with the
Rio Branco. For several hours the
group busied themselves collecting
fishes, angling from the boat, taking
photographs, sight-seeing, and bird
watching. I opted to snorkel in
an effort to observe fishes in their
natural habitats. I was able to
locate dwarf pike cichlids (Crenicichla
regani) and a species of Apistogramma
among the partially-submerged terrestrial
plant growth along the shore. After
a couple of hours of snorkeling,
I decided to do some photography.
While I was taking pictures, Lee
Finley was collecting fishes in
a shallow area in a small inlet.
When we all assembled on the boat
for dinner, Lee generously offered
up his catch, and I became the lucky
recipient of a dozen small chocolate
cichlids!
My twelve juvenile (0.8" TL) H.
coryphaenoides survived the
trip home and were placed in a 340
liters (90-gal) aquarium along with
some of the other cichlids collected
on the expedition. The juvenile
chocolate cichlids displayed a series
of brownish-black vertical bars
with a light orange stripe extending
from the tip of the snout over the
head to the soft portion of the
dorsal fin. They immediately accepted
all foods offered, including live
Artemia sp., frozen bloodworms,
live whiteworms, and small presoaked
cichlid pellets. At this size, H.
coryphaenoides displayed little
aggressiveness among them and almost
completely ignored heterospecifics.
One problem in maintenance noted early on was a sensitivity to free metal ions, particularly copper. The young chocolate cichlids soon began to develop neuromast "pits" (small eroded areas around the neuromasts). It took several weeks to determine the cause of the pitting before a correlation was found between the problem in the fish and the changing of some copper pipes in our building. The easiest solution was to apply a chelating agent with each water change to bind free copper ions, rendering them less toxic. Fortunately, this worked and the pits healed in about a week.
In
the aquarium, chocolate cichlids
grew rapidly on a diet of cichlid
pellets, chopped earthworms, frozen
bloodworms, and frozen Mysis
relicta. Interestingly, they
were very attentive to events at
the surface and eagerly accepted
live mealworms and crickets.
As the fish grew, the barred pattern
gradually gave way to a more uniform
brown ground color with a prominent
black lateral blotch. At the same
time, they also became increasingly
less tolerant of conspecifics, while
remaining remarkably indifferent
to heterospecifics. It soon became
necessary to remove several individuals
in an effort to curtail aggression.
Even this "solution" was short-lived,
as additional individuals again
had to be removed to maintain a
relatively-peaceful community, eventually
leaving only five chocolate cichlids
in the 340 liters (90-gal) aquarium.
When these individuals reached a
length of about 10.0 cm (4") TL,
they were moved to a 475 liters
(125-gal) aquarium which they shared
with seven Satanoperca lilith
collected on the same trip. The
eartheaters though smaller were
completely ignored by the chocolate
cichlids, even during feeding. The
new tank was equipped with a "plant
filter" (Newman, 1997) to maintain
a minimum nitrate level; a double
sponge filter; and a power filter
for back-up and additional mechanical
filtration. Water parameters were:
pH 6.5; temperature 29° C (84° F);
hardness (calcium carbonate) 4.2
mg/1; and nitrate ca. 5.0 mg/1.
The substrate was a fine sand used
to accommodate sifting behavior
typical of S. lilith, while several
large pieces of waterlogged wood
from a local lake provided cover.
Lighting was dim a single 40-watt
fluorescent bulb on a timer set
for about 12 hours a day.
The group of H. coryphaenoides
had been in their new home for several
months when some fry of Pelvicachromis
taeniatus were placed in a 19
liters (5-gal) tank floated in the
larger aquarium (so that an additional
heater was not needed for the fry).
Surprisingly within a day or so,
one of the chocolate cichlids had
developed a parental color pattern
uniformly dark-brown body with
a burnt orange dorsal blaze and
taken up station under the floating
19 liters (5-gal) tank. The dorsal
blaze intensified each time the
guardian fish chased another H.
coryphaenoides or S. lilith
that ventured too close to the floating
tank. It indeed appeared that this
single parental chocolate cichlid
was prepared to adopt the fry as
its own. However, because of the
value of the P. taeniatus,
it was decided (this was not my
call!) that the seemingly eager
parent-to-be would not get a chance
to have any direct contact with
the fry, effectively putting an
end to this unplanned experiment.
Several weeks later when the fry
and the floating aquarium were removed,
the chocolate cichlid reverted to
non-parental behavior and color
pattern.
By
March 1997, members of my colony
of H. coryphaenoides had
grown to lengths of almost 15 cm
(6") TL. During the first week of
March it appeared that two of the
five remaining fish were "tolerating"
each other a bit more than previously.
They were almost the same size,
and it was difficult to determine
the sexes of the two fish. The other
three were confined to the left
side of the tank while the "pair"
spent considerable time together
under the right-side section of
wood. A dead giveaway (excuse the
pun) that the pair had established
a territory was finding a third
fish D.O.A. on the floor, evidently
forced out of the tank through a
small gap in the lid. The remaining
unpaired H. coryphaenoides
also displayed evidence of aggression
(e.g., missing scales and ripped
fins), but it appeared that they
would be tolerated as long as they
stayed at the far end of the tank.
A few days later the pair began to dig under the right-side section of wood, excavating through the 3.8 cm (1.5") layer of sand to expose the bottom glass of the aquarium. Requiring a full week to dig, the pit eventually spanned an area of about 60 cm square (two square feet)! During these digging activities, secondary sexual characteristics of the pair became noticeable. The male was a bit larger and had developed a slight nuchal hump, whereas the female was much heavier in the abdomen. There were however no differences in color between the two. During the construction of the pit, the pair spent a lot of time inspecting the undersides of the wood pieces in the territory. A week after the completion of the pit, the breeding tubes of both individuals became visible, the male's being relatively thin and short in comparison to that of the female.
The
next day the pair spawned on the
backside of a piece of wood nearest
the right end of the tank. Because
egg-deposition took place out of
view, it was impossible to determine
the number, size, and color of the
eggs. However behaviorally, Hypselecara
coryphaenoides spawns in typical
fashion for substrate-spawning cichlids:
the female began with several dry
passes over the site before depositing
eggs on subsequent passes with the
male moving in at regular intervals
to fertilize the eggs. The spawning
was completed in 90 minutes after
which the female took up station
fanning the egg plaque while the
male assumed territorial defense.
Needless to say, the remaining two
chocolate cichlids stayed near the
left end of the 1.80 m (6") long
aquarium.
Two days post-spawning wrigglers were moved to a hollow in a section of wood toward the center of the tank. The male and female took turns transporting the larvae from the spawning site to this new location. Each time a parent approached with a mouthful of larvae, it would signal the other with a lateral display, upon which the second fish would depart to retrieve additional fry.
I waited for five more days (seven days post-spawning) until I thought the wrigglers would be free-swimming to remove a small portion of the brood to insure the survival of at least some of the fry. The sample was removed from the wood hollow with a clean turkey baster and placed in a 19 liters (5-gal) tank floated in the larger aquarium. The incubation tank was fitted with a sponge filter using a mature sponge from the larger aquarium. The fry still with a significant yolk sac were free-swimming the next day. Between the sample in the incubation tank and the fry left with the parents, I estimated that the total brood size was about 300.
Fry readily accepted live, newly
hatched Artemia nauplii as
their first feeding. The fry in
the brood tank were easily fed,
while those still in the large tank
had to be fed via a section of rigid
airline tubing attached to a syringe.
Both groups of fry were fed twice
a day and seemed to process their
food quickly, necessitating frequent
cleaning of the brood tank.
When the sampling of fry was placed
in the incubation tank, the male
left the female and the remaining
brood to tend these "orphans." The
male behaved just as the single
fish had with the P. taeniatus
fry mentioned earlier. After another
week or so, the male began spending
more time with the female under
the right-side section of wood where
she was tending the mobile fry.
The parents frequently signaled
to the bottom-oriented fry with
rapid flicking of the pelvic fins.
In instances of excessive disturbance,
such as during feeding, the color
of both the male and female intensified
(black body with bright, burnt-orange
dorsal blaze) signaling the fry
to sit motionless on the bottom.
For the most part the fry were kept
in the spawning territory with only
brief excursions toward the middle
of the tank. As regards the other
fish in the aquarium, the pair practically
ignored S. lilith except
when one of the latter ventured
too close to the mobile fry; in
sharp contrast, both members of
the pair regularly traversed half
the length of the aquarium to reinforce
their dominance over conspecifics.
At the end of every day, just before
the timer switched off the light,
the fry were gathered together under
the wood near the spawning site,
sitting motionless on the sand bottom,
presumably for the night.
The 19 liter (5-gal) floating aquarium was removed in a week after which the pair invested their undivided attention on the fry still in the larger tank. At this time I stopped feeding brine shrimp to the fry; after three weeks there were only twelve left. They apparently survived by feeding on small particles of flakes that were fed to the adults.
Quite suddenly the female began hunting the remaining fry, a sure sign that she was preparing to spawn again. However, the male persisted in defending the fry, leading them to a station on the top side of the wood out of view of the female. Over the next couple of days the female worked in the pit, cleaning the site that had been used for the first spawning. The next sign that a second spawning was imminent was the torn fins and damaged scales of one of the other resident chocolate cichlids. The next day the female was much slimmer and reluctant to leave a site under the wood, while the male, continuing to defend the fry from the first spawning (now numbering only four) patrolled the territory perimeter.
Two days post-spawning, the eggs
hatched and larvae were placed in
the pit on the bottom glass of the
aquarium beside a small piece of
wood. Several days later the fry
became free-swimming; again, I removed
a sample of the brood to rear under
safer conditions. Unfortunately,
I timed the removal of the fry quite
badly. I used a small, fine-mesh
net to collect the sample which
created significant panic with all
the cichlids in the tank, especially
the parental chocolate cichlids.
The remaining fry were quickly dispersed
throughout the aquarium and easily
eaten by the other chocolate cichlids
and resident S. lilith. The
sample that had been removed was
placed in a 57 liters (15-gal) rearing
tank and started on newly-hatched
Artemia. They grew very rapidly
and within three weeks were feeding
on chopped frozen bloodworms and
crushed flakes.
Three weeks later the same pair
spawned in the same place for the
third time. Having little room to
rear additional chocolate cichlid
fry, I decided to leave this third
spawn in the home aquarium to observe
parental behavior and fry survival.
A day after the fry became free-swimming,
one of the S. lilith got
a little too close to the shoaling
brood. The male chocolate cichlid
attacked the S. lilith and
managed to score a bite from the
flank of the fleeing demonfish.
As the eartheater darted away, a
flurry of scales were left in its
path. Before returning to the brood,
the male H. coryphaenoides
enthusiastically devoured the scales
as they settled onto the sand.
Despite diligent parental protection, the number of free-swimming fry was quickly reduced by opportunistic predation by the other fishes in the aquarium. At about three weeks postspawning, the female became ripe again and began to eliminate the remaining fry herself from the spawning territory. Based on such observations, it seems that only low fish densities combined with complex shelter would allow for recruitment of juveniles to the community at large.
For the hobbyist with one or more
large aquariums looking to keep
something a little "exotic," the
Rio Negro chocolate cichlid, Hypeselecara
coryphaenoides, with its complex
parental behavior and spectacular
color changes, could be just the
ticket. It is somewhat demanding
to keep in terms of space; they
reportedly grow to 20-15 cm. (~8-10")
TL under suitable conditions in
the aquarium and certainly come
by their aggressive reputation honestly
(Leibel, 1996). However, a point
in their favor is the fact that
they do spawn at sizes far less
than their eventual maximum. Also,
the majority of their aggression
is directed toward conspecifics.
If one resists the temptation to
house more than one pair and a couple
of conspecific targets in the same
tank, their aggression is moderate
at worst.
As many cichlid keepers know, there
are several techniques one can employ
to secure the safety of large, aggressive
cichlids engaged in reproductive
activities in less than spacious
quarters. However, giving this fish
an opportunity to express its natural
behaviors under conditions similar
to what it would encounter in the
wild (i.e., low conspecific and
heterospecific densities and enough
space to chase intruders beyond
the territorial boundary) allows
the hobbyist to observe the very
behaviors that make cichlids so
interesting and popular. Hypselecara
coryphaenoides is easily fed
and relatively easy to spawn, and
for the aquarist willing to provide
a large, heavily-aquascaped aquarium,
it can be an interesting addition
to a community of South American
cichlids. □
References Cited
