Alternative name Rivulus (Oditichthys) collieri. Previously misidentified as: Rivulus ornatus.

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Keeping and breeding is not easy and 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 aggressive to each other and fight to become dominant to others. The best way to have much offspring is to put a group or an trio in a shallow tank from 30 liters with a small filter in it or with some aeration. On the bottom some peat moss or dark gravel and a floating "mop" to give space for laying there eggs. Very good results are recorded if the species has lots of Riccia fluitans or other floating plants like Azolla used as hiding places and by leaving the eggs and later the fresh born juveniles in the tank with the parents. The fish will, if they become a rich variety of small sized life food, spawn during there whole adult life and a good pair produce daily between 3 to 8 eggs.

If not set up as explained above the eggs should be collected by hand and stored for about 14 days in a small container. Eggs are 1.6 mm and amber colored. It is wise, to add to the water you store the eggs in, some acryflavine to prevent fungus coming up.

After hatching the young fry can eat fresh artemia nauplii after a week and will live also from small infusoria that are attached to the plants. It takes 4 to 6 months to raise them to maturity.

There lifespan can be up to 3 years in captivity.

Remarks :

From above the fry looks black colored and show a illuminated spot on the head like in Epiplathys from Africa. They are almost always dwelling at the surface and loose this spot after a month.

To the right the image of one of the males from Thodor Metchko, Bulgary. With missing ventral fins.

To the right a R. collieri without any black pigmentation. This one was born out of the strain of Sue Katz, USA.

Below R. collieri from Caserío san Andrés and at the right from South West Peru.

Below: The R. collieri from San Andres, collected in 2022 during a combined trip to Peru and Colombia.

At the left you see an image of Rivulus obscurus from Rio Purus, not far from Manaus, Brasil. As stated above there is an ongoing discussion about which species was given originally the name Rivulus ornatus by Garman in 1895 . Some scientists believe the fish, shown here at the left, should be named as Rivulus ornatus. The one at the top is, since 2021, described as Rivulus collieri by Huber.

At the left here you see 2 scanned slides from the early 1980 's showing a R. collieri, then known as R. ornatus, male and female from Padre Isla, Iquitos, Peru, the type locality. This fish was collected by Patrick de Rahm, Switzerland.

Rivulus (Oditichthys) collieri - South West Peru. © Image made and donated by Guillaume Dethu, France.

Rivulus (Oditichthys) species "Libertad", from the upper Napo River, collected in 2022 behind the village "Libertad". © Image made by Frans vermeulen.

Max. size 3.5 cm.
Dorsal 7.0,
Anal 11.0,
D/A 10.1,
LL scale count (average)30.1
Pre- dorsal length to % SL – 79.0 %
Depth to % SL – 18.0 %

Huber J.H., 2021. A new, but since long misidentified species, Rivulus collieri from Peruvian Amazon (Cyprinodontiformes, Rivulidae) Killi Data Series 2021, 6, figs 1a,b-2a,b.

Costa, W.J.E.M., 2011. Phylogenetic position and taxonomic status of Anablepsoides, Atlantirivulus, Cynodonichthys, Laimosemion and Melanorivulus (Cyprinodontiformes: Rivulidae). *Ichthyological Exploration of Freshwaters* 22 (3): 233-249