Procatopus aberrans Ahl 1927

Procatopus gracilis (now aberrans).
Photo: Courtesy of Ed Pürzl

Meaning of Name

From Kadlec (BKA K/N 272) Pro = front, cato = hold, pous = foot.
aberrans is derived from aberratio = deviation, divergence.

First Description



6 cm. Females can be 2 cm smaller.


D = 7-8, A = 15-16, ll = 30 (from type specimens ?).


n = 25





  • Procatopus gracilis Clausen 1959 (This form was seperated by a light area in the caudal fin which was missing. Later cross breeding data proved this naming to be invalid).
  • Procatopus andreaseni Clausen 1959
  • Procatopus nigromarginatus Clausen 1959
  • Procatopus plumosus Clausen 1959
  • Procatopus roseipinnis Clausen 1959
  • Adoro
  • Kumbe
  • Nigeria
  • Osse River
  • DKG Red

Male collected in the Niger Delta.
Photo courtesy of Ed Pürzl.

- Collected in June/July 1977 by Fred Wright, Road Roberts et al near the village of Adoro in the Anambra drainage, Northern Nigeria. This biotope was a strongly flowing turbid stream in primeval forest which only received light in areas where the road crossed it.
At 13.45 hrs water temperature 79°F pH 6·3, DH 2, water depth 1 - 4 feet was recorded. Few aquatic plants were present, the stream flowing over laterite & clay with a heavy covering of rotting vegetation.
This was the only sp. of killifish found. Other sp. included were Characin & Cichlid.
Another stream close by had a stony base with a swift flow. This was 30 feet across in parts & 4 feet deep.
Type Locality

Four specimens were collected at Ossiding near Eyomojok. These were deposited in the Zoological Museum of the Humboldt University in Berlin.




Found in rainforest streams near savannah areas. Also found in savannah areas of Nigeria & Cameroon.

Distinguishing Characteristics 
Colour/Pattern Variability 


Breeding Notes

A breeding report appeared in BKA newsletter No. 154, June 1978 by P.Goris who used water with a neutral pH & no harder than DH 10. Eggs were laid in fissures near the water surface, cork, bark, stones etc. The female was observed to eject the eggs with such violence that they would attach themselves to bark above the water surface. Finding eggs in wet bark was considered very difficult & the bark was dried off for 10 minutes prior to collection.
Eggs were incubated in a solution of Typaflavine at 24°C. Fry hatched in 15 days, with the first food being micro-eels followed by newly hatched brine shrimp a few days later. Fry are slow growers reaching maturity after about 12 months.
It was observed that placing young fish in fresh water should be avoided as they are very sensitive to sudden changes in water.

Jaroslav Kadlec in BKA K/N No. 272 (April 1988) reported water quality for breeding not too critical with a temperature range from 20-26°C, 8-13DH, pH 5·8-6·8. Nitrite & Nitrate levels should be kept low.
Females will produce 10-20 eggs per week.
At 20°C eggs will water incubate for about 20 days. At 25°C the incubation time is cut to 12 days.
Fry were observed to always hatch at night. It was observed that a number of eyed up eggs failed to break through the shell. Fry on hatching measured 0·6-2mm. They were transparent & ate on the first day infusoria & Cyclops nauplii.
At one month only 12mm growth size was attained. After 3-4 months only 20mm was measured. It was not until the young were 9 months of age than the blue sheen to males emerged. First breeding attempts were observed at 12 months of age.

Jacqueline Cammidge wrote an article in BKA newsletter No.375, December 1996. Breeding tank was a 12 x 8 x 8" filled to 4" of water. Water temperature 78°F, pH 7·4, GH 25. A sponge filter was added to stimulate flow rate plus a floating mop. The mop was inspected after 3 days & 32 eggs were found which were pushed into small crevices. Eggs were found near the surface in the mop & cork. A sponge was tried to see if they laid in this but they preferred the mop.
After 18 days the eggs hatched & were fed micro worm. After 14 days they were fed newly hatched brine shrimp.

Diameter of Egg 

Full size is attained at 14-18 months of age. Reports suggest they are long lived, reaching 4 years of age.