Manuel Zapater Galve, 2000
Cichlid Room Companion
Breeding tanks

Archocentrus myrnae Loiselle, 1997

By , 2000. image

Classification: Captive maintenance, Central and North America.

Archocentrus myrnae

Archocentrus myrnae female taking care of her fry in the aquarium. Photo by Manuel Zapater Galve.

A new cichlid for our aquariums in Spain.

Archocentrus myrnae, a species that was described in 1997, originated from a subsidiary of Sixaola River in Costa Rica, a river that runs along the border between this country and its neighbor Panama. It was collected by Juan Miguel Artigas Azas, who gave me these data for the purposes of writing this article: water is clean, shallow and flows rather rapidly. It has a sandy bottom. Temperature reaches 26° C in Spring, pH is alkaline, at about 8.4. It lives in company of another cichlid: Astatheros bussingi.

If I have to be sincere, I didn't know the kind of fish that Juan Miguel was proposing me, but I heard José Luis, A mutual friend visiting Juan Miguel, speaking quite well about their good looking, resistance, and being tolerant enough to live with smaller fish in the same tank. Having kept African cichlids for a long time, I didn't know the species it was, which wasn't helped by the fact that there was quite a confusion between these fish and another very similar species: Archocentrus septemfasciatus.

Then in January 2000, after a long flight, a small group of five fish arrived in Spain. Three of them were clearly bigger than the other two, but these small two showed a dark spot on their dorsal fin. Their body shape was rounded as in other members of their same genus, fins were transparent but for the spot on the dorsal fin of the two smallest fish. Their color patter was light brown above the longitudinal line and metallic yellow below it. Nevertheless, at first sight, their most striking feature was their electric blue iris.

Archocentrus myrnae male
Archocentrus myrnae female

Male (above) and female (below) of Archocentrus myrnae in the aquarium. Fish and Photos by Manuel Zapater Galve.

Archocentrus myrnae female

Fry of Archocentrus myrnae in the aquarium. Fish and Photo by Manuel Zapater Galve.

They first looked like shy fish, although they didn't seem to have any problems accepting the food I offered them. They were housed in a 80 l (aprox. 20 gal) tank in company of some Xiphophorus helleri, that were meant to act as a dither fish. I thought this volume wasn't enough for all of them, so I moved them into a 120 l (aprox 30 gal. Tank). They grew rapidly and a certain stress started to show among the males. As I didn´t want to take any risks with such a locally rare species, I set up the tank which was meant to be their definitive house, a 1 m x 40 cm x 50 cm (200 l, aprox 50 gal) decorated with three big logs that I had been seasoning for nearly one year, a light yellow sand layer; a dozen Java ferns (Microsorum pteropus) and a few individuals of Cryptocorine sp. And Crinun thaianum represented the vegetation. Behind the logs I set up some clay flower pots and a couple of cocoa nuts that I hoped they could be good breeding substrates. The only fish that shared the tank with them was a group of wild type guppys which were bought by Jose Luis in a fish store in México.

I thought that the best way to get a couple would be to isolate a male and a female in this tank, once that I was sure that the two filters, a external EheimTM and a internal sponge AzooTM were working appropriately, and the water looked in excellent condition if one had to look at the guppy's rate of growth. The temperature was set at 26° C, every week I renewed 25% (50 l) of water. The chemical values of the water were the following ones: pH: 7.8, hardness 20 °GH, temperature 26° C. The tank was illuminated by two fluorescent lamps of 30 w. each, for 10 hours a day.

I fed them on home made paps of white fish and vegetables, frozen brine shrimps and live black mosquito larvae (Culex sp.) and Daphnia. They seem to enjoy this live food much better than detritus and vegetable wastes that are quoted in the literature as their main source of nutrients in the wild. In spite of this good maintenance, I didn't see any kind of matchmaking, they spent all day hiding among the logs and ignoring each other. I supposed that perhaps if I added the other three fish, this two would start to defend their own territory, which could lead them to breed.

What I was looking for didn´t take long to happen, one week after the rest of the cichlids were introduced in the tank, the first couple that was living there took charge of the left quarter of it, which was the place where I usually supply the food. The color pattern of the female changed dramatically, showing a big copper spot on her tummy (like the one that happens on A. nigrofasciatus females), the ground color turned into light brown and her head and lower part of the body were now completely black. The male became now more aggressive (if this fish can ever be so), not allowing the rest of the cichlids and poecilids to get into their territory. He kept his original color till one week later. Seven days later I saw that male and female had their ovipositor clearly conspicuous. They went every now and then to the back side of the tank where I could not see what was happening. I finally found that the eggs had been laid in a cave in the wood, which measured about 10 cm long, 4 cm wide and 4 cm deep.

From that moment I only had to wait for the day that the fry would be swimming with their parents. Unfortunately I hadn´t been able to witness the egg-laying, but I already knew that another couple was ready to breed in the other corner of the tank.

This happened in a clay pot, that was much better placed in order to see what was going on in there, it was the same day that the first couple brought their fry into the open waters of the tank. The female was catching the male's attention towards the pot that she had previously cleaned. She spread her fins and shivered perpendicular to the male, showing the bright color on her tummy. Bit a bit, around 150 eggs were laid in the upper part of inside of the pot. From this moment on only the female took care of them having the male the responsibility of protecting the territory. Four days later, the newly hatched larvae were taken in the female's mouth and moved into a cocoa nut, where they would stay for one more week until a group of more than a hundred fry swam around the tank searching for food. This second couple, being slightly bigger than the first one tried to get a territory as vast as they could in spite of the thirty young fry of the first couple, which measured now more than half a centimeter.

The fry fed on anything edible that they found in the tank, but liked above all newly hatched brine shrimp's nauplii, which were distributed at least five times a day, using a syringe to drop them above the cichlid fry. The only problem I found for this way of feeding them was the fact that half the Artemia nauplii were eaten by guppys as they were falling in the water (anyway, this has helped me to get quite decent guppys).

Parental care are excellent from every point of view, being the female always above the fry and the male over them taking care of the whole group. Fry's response seems to be triggered by the black colors of their parent's pelvic fins. I have to tell now that I chose the guppys as school fish because I had not noticed them preying on their own fry, so neither expected I them to prey on cichlid fry, which has shown to be true. In correspondence, cichlids are not preying on viviparous fry either, and their numbers are rising too fast.

Summer heat in Spain does not seem to be too good for the cichlids, we reach nearly 30° C in the water this year, which together with over population of 2 cm. long cichlid juveniles (which are completely tolerated in parental territories), looks like it has stopped breeding so far (as I am translating this article into English, and following a drop to 24°C of water temperature, I have a new set of eggs ready to hatch).

I find it a very attractive species, whose behavior is good enough to live with smaller fish, and it may soon become a popular fish in our tanks due to their size and easy breeding. I hope this brief article may be useful to make it popular among cichlid lovers.

Archocentrus myrnae

Archocentrus myrnae breeding tank. Photo by Manuel Zapater Galve.


Zapater Galve, Manuel. (Aug 07, 2000). "Archocentrus myrnae Loiselle, 1997". Cichlid Room Companion. Retrieved on Sep 23, 2023, from: