Rivulus uroflammeus, Bussing 1980

History

Alternative name Cynodonichthys uroflammeus.

The type locality of Rivulus uroflammeus is Costa Rica. It was first found near San Vito landingfield, tributary to rio Cotos Brus, Puntarenas Province. The species is living on high altitudes and the terra tipica was on 990 meters above sea level.

First discovery was made by Peter Siegfried on October 14, 1978.

The name refers to the flame colored caudal peduncle and comes from the Greek word "oura" and the Latin word "flammeus".

 
Rivulus uroflammeus, male. (PBS 00-02) © Image made by F. Vermeulen.

Reproduction

Keeping and breeding is easy but a good cover of the aquarium is necessary because there ability to jump, even true the smallest opening, is unbelievable.

This species can, if there is enough space for them, housed in a tank with more males than one only and several females. If separated before and brought together again however, they can be very agressive to each other and fight to become dominant to others. The best way to have much offspring is to put a pair or an trio in a small tank from 10 liters with a small filter in it or with some airation. On the bottom some peat moss or dark gravel and a floating "mop" to give space for laying there eggs. The fish will, if they become a rich varity of life food, spawn during there whole adult life and produce daily between 5 to 15 eggs.

The eggs should be collected by hand and stored for about 14 days in a small container. Eggs are 1.3 mm and amber colored. It is wise, to add some acryflavine to the water you store the eggs in, to provent fungus coming up.

 

After hatching the young fry can eat fresh artemia nauplii without any problem. It takes 4 to 5 months to raise them to maturity. Often the number of males is far above the number of females. For some species this can become a major problem for the breeder as he has to raise many young fishes and so become able to distribute a few pairs to other hobbyists. Recent personal tests laerned that lower pH levels during the time of hatching gave a higher percentage of females. To achieve this I use some peat moss that I add to the container with the egss just before they are ready to hatch. This peat moss also is a good way to prevent eggs to become attact by fungusses.

There lifespan can be up to 3 years in captivity.

Remarks :

This species is also known by the name R. uroflammeus uroflammeus.


Variations
     

Map
     

Meristics

Max. size 6.0 cm.
Dorsal 10.7,
Anal 14.7,
D/A 8.5,
LL scale count (average)33.2
Pre- dorsal length to % SL – 72.3 %
Depth to % SL – 23.1 %

   

Literature
Bussing W.A. 1980. Status of the Cyprinodontid Fish Genus - Rivulus in Costa Rica with descriptions of new endemic Species. Brenesia, San Jose, 17: 338, figs. 2B, 5B, 6B.