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Marcelo Casacuberta, 1999
Cichlid Room Companion
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Gymnogeophagus labiatus, 2001

作者 , 2001. image
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類別: 強制維護, 南美洲.

Gymnogeophagus labiatus pair

Gymnogeophagus labiatus pair in the aquarium. Photo by Marcelo Casacuberta.

One of the most beautiful and elusive cichlids that can be found in Uruguay is, without doubt Gymnogeophagus labiatus.The scientific name of the species is clearly referred to their thickened and swollen lips, believed to help them to find food in murky bottoms.

Although it is a big fish, males reaching 17 cm, it is rather shy and not so aggressive if compared with other South American cichlids. In fact I wouldn't recommend mixing them with rougher South American species, like Cichlasoma facetum or G rabhdotus.

Sexually mature males develop a big cephalic hump, and show a beautiful amber yellow head, with a black vertical band running from the eye to anterior operculum. Pearled blue scales make the sides the of the body sparkle . The male shows bright blue dots decorating the head, but the most appealing feature are the dorsal and caudal fins decorated with bright blue and red stripes.

Females are much smaller, measuring about half of the male's size and lacking his bright colors. Females show some wide black vertical stripes on a light brown background. A big black rounded blotch is clearly noticeable in the middle part of the body, and the eye stripe is much darker than in males. Their dorsal fin is short and rounded showing only hints of red and blue.

In general terms, G. labiatus resembles Gymnogeophagus gymnogenys but have a more elongated body shape (specially males) and their main color is blue and green whereas G. gymnogenys tends to show yellow, red and amber in their scales and fins. Although both species can be found together, G. labiatus seem to prefer rocky areas, while their close cousins are most commonly found in sandy bottoms.

In Uruguay, G. labiatus are found in the north of the country, and show a limited range, mainly in the Yaguaron river (Centurion zone) and in the Olimar and Yi river systems. Being hard to find, they are seldom kept by hobbyists and thus little is known about them and their breeding behaviour.The species is also found in Brazil, but in Uruguay (the southernmost distribution of the species) they have adapted to sub-tropical conditions, with temperatures dropping around 12C in winter. They share the habitats with other cichlids species, including G. meridionalis, a direct competitor for food, Crenicichla punctata and C. lepidota, that prey on labiatus fry.

G. labiatus must also be alert to avoid predatory fishes like some big Pimelodus catfishes, Piranhas and Hoplias. As most of the "eartheaters", they tend to feed from the bottom and seem even a little clumsy when trying to take sinking pellets or flakes in the midwater zone. They are not fussy at all and take most of dry and frozen foods. However, tubifex and other live food should be offered when conditioning the fish for spawning. In spite of their massive head and big jaws, they seem to have problems swallowing big pieces of food, so chopping meaty morsels like mussels or earthworms to small bites is a good idea.

The most fascinating thing about G. labiatus is their breeding strategy, described as "larvophilous mouthbrooders"

Besides the bright colors of the male, and their mild temper, the most fascinating thing about G. labiatus is their breeding strategy, described as "larvophilous mouthbrooders". In this, spawning takes place in a rock or other surface where eggs remain until the female takes them in her mouth, about two days later, when they are starting or next to hatch. Several cichlid species follow this breeding pattern, laying their eggs in the sand, rocks or even over dead tree leaves that they can move away if they feel threaten. Several theories about reproductive methods in fish claim that mouthbrooding is an "advanced" behavior evolved from the original substrate spawning. Following this path, could it be possible to consider the labiatus type of strategy as an intermediate one, theoretically evolving towards the classical mouthbrooding?

My group of G. labiatus (one male and three females) share a 150 litters tank with a few small G. australis and some serpae tetras that serve as ditter fish. Females seem to have a pecking order with a dominant female that chases away the others whenever they meet. Females hold small territories in the tank and remain always close to them, moving away only to look for food. Territories were kept permanently by females and not only when spawning is imminent. The size of the territory seems not to be the main selection factor, as in my tank, the smallest female keeps the biggest cave. A small flat rock, covered with other stones and hard to reach for other fishes, is a much more desired possession. The male, on the other hand, cruises around the whole tank not showing interest for a favorite spot. In the wild, this species is supposed to live in a haremic structure with several females living within a big territory that is defended by the male, acting almost like a giant type of Apistogramma.

Rio Yaguaron

Rio Yaguaron, habitat of Gymnogeophagus labiatus. Photo by Marcelo Casacuberta.

It seems to take them a while to fully adjust to a new tank and some weeks may go by before they show any breeding impulse. The male will display to the females spreading his fins and trembling, always close to the bottom, near a potential spawning place in a style that closely resemble those of mbuna males. Courtship movements of the male include body shaking, fins spreading and a heavy chewing action, emphasized by strong nodding movements of the head. The male makes strong, fast movements with his thick lips, just as if he were trying to swallow a big mouthful. I had witnessed a similar courtship display in males of G. gymnogenis. If the female is not willing to spawn, she shows no interest in the males dance, ignoring him or slowly swimming away, but if the male becomes too insistent, she might nibble in his forehead to make it clear she is not ready. In fact the females tend to act uncomfortable whenever the male comes too close to the domains of any of them. It seems that the male has full access to a female territory only when spawning is about to take place.

The male in my tank became highly interested in the dominant female (lets call her number one), as she appeared to be almost ready to spawn. He used to stay close to her, even when she showed her disagreement nibbling his head or sides. After a while she ended tolerating him nearby her territory for extended periods.

Finally, the secretive spawning took place under a hidden rock, right in the middle of the female's territory, and I was aware it had occurred only when I saw the male in the opposite corner of the aquarium. About thirty eggs were laid on a flat stone, in a compact round spot about the size of a grape. In the wild, the female helps the eggs to remain unnoticed spitting sand over them , to hide it from potential predators. The egg's size was small if compared to those of typical mouthbrooders, and measured about 1 mm, they looked just like laid by any substrate spawner cichlids. The female protects the spawning chasing away any wandering fish that comes near, including the male, that seems to take no significant role in parental care besides guarding the territory.

The next day, the female collected the eggs one by one after unsticking them from the stone with strong jaw movements. Normally, the female waits until the larvae free themselves from the egg shells before picking them. This is supposed to happen 50 to 60 hours after spawning, depending on water temperature. Collecting the eggs seems to be a slow process, that takes a couple of hours as the female takes a close look to each one before taking it, discarding the ones that are fungused or have turned white.

Her pouch didn't looked as distended as in Malawi holding females, but I thought this was due to the smaller egg size. Not having witnessed the spawning, I wasn't sure that the male had really fertilized the eggs, that looked a little bit paler than the expected amber color. When I fed the fishes that afternoon, the female shown no attention to the flakes, so I supposed things were working fine, but the next morning she was eating just as usual, and after five days without any change, I assumed the eggs had been eaten, perhaps because they weren't fertilized and wasted away. I was surprised that the female remained in her territory even after collecting the eggs, even tough there was nothing to protect.

A week later, another female (number two) had laid another batch of eggs, but strangely they were placed far away from her territory, on the bare bottom of the tank , and only five centimeters away front the front glass. This made it hard for her to protect the eggs, as every time somebody came across the tank, she looked for shelter among the rocks in her territory, leaving the spawn on it's own. In the long terms, this led female number three to eat the undefended eggs. Only ten days after her first attempt, female number one laid a new batch in the same spot, but once again no fry were produced.

Spawning size ranged among forty and sixty

To compensate the unsuccessful spawnings attempts of my trio, I was lucky enough to get some holding G. labiatus females that were caught by my friend Felipe Cantera, an expert collector of Uruguayan fishes. Unlike my females, their buccal cavity was really expanded, but I noticed that this was because the embryos had already hatched. Not having a holding tank for them, they were placed in my communitary tank, but as I was afraid of the fry being released in a tank full of potential predators, I was forced to do something I usually avoid: stripping them. This proved to be a strange event, as the fry tried to re-enter the poach as I kept the mother's mouth wide open. Spawning size ranged among forty and sixty .Under normal circumstances, the fry are released from the mother's mouth after eight days, but they are taken inside again at any sign of danger. Perhaps as it happens with mouthbrooders, the fry seems to absorb the yolk sack slower than other cichlids do. About four days after being stripped, the dark little ones started to eat Artemia, but still carried half of their yolk. They grow fast on the first weeks, but then slow a little they growth rate. They show a black "chessboard" like pattern, that slowly changes to stripes when they reach two months old. Measuring one inch after three months, they should be ready for spawning in the next summer, when they are one year old.

Coming from the north of Uruguay, near the Brazilian border, G. labiatus enjoy warmer temperatures than other local cichlids, feeling comfortable between 20 and 26C. Neutral or slightly acidic water seem to suit them better, and plenty of driftwood or rock caves as hiding places make them feel safer. Considering their size, a tank at least 160 cm long should be considered. As with many eartheaters, good filtration is needed to take care of all the fish's sifting, but water movement in the tank should be kept at medium levels. As I learned, patience seems to be the key to success with this amazing but elusive creatures. Future experiences will help to gather all the pieces for the puzzle of their breeding cycle.

Gymnogeophagus labiatus female

Gymnogeophagus labiatus female guarding her tightly packed eggs in the aquarium. Photo by Marcelo Casacuberta.

引語

Casacuberta, Marcelo. (12月 30, 2002). "Gymnogeophagus labiatus, 2001". Cichlid Room Companion. 檢索 3月 28, 2024, 來自: https://cichlidae.com/article.php?id=174&lang=zh.