History

Described in the genus Cynolebias.

2023, moved to genus Matilebias.

It was Alexander Fernandez-Santo, the son of one of the two collectors (J.O Fernandez-Santo and J.Castelli) that died just as the description of this species was planned to get public. The describers dedicated Alexander's name to this new species and named it Cynolebias alexandri.

The image below shows Mr. J.O. Fernando - Sanches at the KCA convention in November 2008.

The first discovery took place long before the actual description and was done by mrs. M.I. Elizalde at April 17, 1941 but the species was rediscovered at Parque Unzué, Gualeguaychú, Provincia Entre Rios, Argentina by both aquarists mentionned above at July 20 1972. Two years later the description followed.

Click here to see Breeding video

Copy-past the links below to your browser to see some amazing videos from the KCA Study Group and the people who appear on the video are: Ignacio García, Pablo Calviño, Celeste Roldán and Felipe Alonso.

http://youtu.be/iVG6_PFjD5w

http://youtu.be/5KJhvQN3Nc0

To breed most Austrolebias, you will need an aquarium with about 10 to 25 liters of water in it, a small pot or plastic container about 10 to 15 cm high, a little well-cooked peat moss, or cocopeat, and a water temperature between 18 and 24 C. It is wise to add a small filter to that aquarium and change the water 90 % regularly. Austrolebias do prefer soft water of Neutral pH between 6.5 and 7.5. Introduce a male and, if possible, two or more females into the tank and feed the fish daily with live food such as daphnia, red- and black mosquito larvae and white worms or tubifex. Austrolebias do not readily accept dry food, nor is prepared cow's heart preferred when offered live food. If possible, breed this genus in larger tanks with more than one pair or trio and provide some hiding places if you do. If you breed with more than one male, you should also provide more than one breeding container. When possible, each male should have one, and you will find that they exhibit interesting territorial behavior to lure females to their breeding sites.

The male "flutters" around the female, showing his fins with the most intense colors. When the female is ready to spawn, she follows the male, pressing his head to the peat layer, and when the female touches the male's belly, they both dive into the peat layer. This layer should be at least as thick as the length of the largest animal or, better yet, a little deeper so they can dive all the way in.

Spawning occurs throughout the fertile life of the fish, starting at an age of 5 to 6 weeks, until they become old and weak or die due to the lack of water in their natural environment. This "end of life" is within 8 to 11 months, depending on temperature. Higher temperatures lead to faster aging.

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In the wild, Austrolebias live in colder environments in winter. Temperatures in Uruguay, Paraguay, and Argentina can get very low up to freezing temporarily. The incubation period is usually six weeks if kept at high temperatures (25°C) and longer if kept at lower temperatures. Development can also take five to six months. It is therefore wise to check the eggs regularly to see if the eyes in the eggs are fully developed and the iris is clearly visible. If the eggs show "eyes," place some of the peat with the eggs in water at a cool temperature (about 18 C). If the young usually hatch and swim within a few hours, wet the rest of the peat. After hatching, feed the young immediately with fresh-born Artemia nauplii. A day or so later, I drain the water along with the young and place them in a well-filtered tank without peat moss to grow up. Austrolebias are not used to strong currents and young fish can die if the turbulence is too strong. The remaining peat still contains eggs that are not yet ready to hatch. Repackage the peat and store it for some extra time. This delay in hatching is nature's response to brief rains that fill pools only temporarily, followed by another dry period. Such an event would wipe out the entire population of the species in that area if all the eggs were to hatch at the first rains. These (late) eggs will hatch later, sometimes very much later, and the adult fish born earlier will eat most of these young.

As mentioned earlier, the young grow quickly and will produce their first eggs after 5 to 6 weeks, if not sooner. This breeding information applies to most Austrolebias. However, if the above Austrolebias species show abnormal behavior or have extreme adult sizes, you will find these modifications below in this section under <Remarks>.

Remarks:

Castello, H.P. & R.B.Lopez. 1974. Cynolebias alexandri, a new Species of annual Killifish from Argentina, with notes on C. bellotti. Trop.Fish Hobbyist, 23 (9): 35, fig.

Alonso F., G.E. Terán, W.S. Serra Alanís, P. Calviño, M.M. Montes, I.D. Carcía, J.A. Barneche, A. Almirón, L. Ciotek, P. Giorgis, J. Casciotta, 2023. From the mud to the tree: phylogeny of Austrolebias killifishes, new generic structure and description of a new species (Cyprinodontiformes: Rivulidae) Zool. Journ. of the Linnean Society, XX, 1-30, Fig. 15, Tab. 2.