Aphyosemion cognatum Meinken 1951

A.cognatum Photo courtesy of Ed Pürzl.

Meaning of Name

cognatum meaning related. When they were first described they were thought to be related to A.calliurum & A.striatum.

First Description

Meinken H, 1951.

Aphyosemion cognatum eine neue Zahnkarpferart aus dem Congo Gebiet.

Die Aquarien und Terrarien Zeitschrift. IV. 10: p255-257 (258?).

Size

5 cm (Radda & Pürzl 1987).

Meristics
  • D = 8-9, A = 13-14, ll = 30-31 (Meinken 1951)
  • D = 9-11, A = 14-16, ll = 29-31 (Radda & Pürzl 1987)
Karyotype

n = 13-15, A = 18 arms. (Scheel 1990. Scheel recorded n = 12 in one population). This is variable between populations.

Sub-Genus

Aphyosemion

Group

elegans

Synonyms
  • Aphyosemion elegans (non Boulenger 1899); Boeseman 1957
  • Aphyosemion decorsei (non Pellegrin 1904) Wood 1976 (Kisantu population).
  • Aphyosemion sp. Kwambila BKA SIC import 1980.
  • Aphyosemion sp. Madimba BKA SIC import 1980.

Populations

  • Bandundu (Central Zaire)
  • Djoué (southern Congo)
  • Kenge - Kimuenza ('Kimwenza' is most probably a corruption of spelling).(western Zaire)
  • Kinshasa
  • Kinsuka (has been spelt Kinsuhka in some publications).
  • Kintepe
  • Kisantu (Geoff Wood 1975. Originally distributed as A.cognatum decorsei).(northern Zaire)
  • Kwambila (A small brook behind the riding school of Kinshasa).
  • Lutendele
  • Madimba (Wachters 1979).(western Zaire)
  • Maindombe River
  • Ma'Vallee
  • Mbanza-Ngungu
  • Mbamou Island
  • N'Galiema
  • Ngangalin-golo (southern Congo)
  • Nyangu-Cugolo
  • C I I / 13
  • HZ 85 / 2
  • RPC 153
  • Z 82 / 2. (15km south west of Mbanza Ngungu)
  • Z 82 / 18. (Kenge, Wamba River)(central Zaire)
  • Z 82 / 22. (Pool Malebo)
  • Z 91 / 3. (Kenge)(central Zaire)
  • Lake Fwa (A.aff.cognatum) (Kasai Oriental Province), southestern Zaire)A distant (presumeably isolated given present collection data) population to the east-south-east of the concentration of distribution for A.cognatum. They were available to the BKA mid to late 1990's but I didn't see them. Although only one location is specific to this population it has picked up many names in captive circulation -
    • A.affinis cognatum Lake Fwa
    • A.sp.Lake Fwa
    • A.cognatum Lake Fwa
    • A.lujae Lake Fwa

An Epiplatys from this Lake has also been distributed. See Aqualog Vol 2 page 56 for photo.

  • Tirbak's Strain (See Aqualog Vol 1 page 75 for photo)
  • H1. Unknown code from the KCF.
  • CI 05. USA import in 2005 collected at Kinsuka.
  • RDC 07 / 01 - Kwambila
  • Congo CI 11


Bandundu - Collected by Kees Klute (a Dutchman) in September 1982 250 km northeast of Kinshasa on the Kwango River, Central Zaire. Also collected were E.aff.multifasciatus.
Some males from this collection have a very broad submarginal dark red band inside the broad blue outer marginal band of the dorsal. Also, the red spots on the flanks join to form irregular transverse stripes. It has been reported that some males have a lemon yellow anal fin whilst others have a green to bluish green anal.

Bandodo I kept this population in the early '80's but this spelling may be a corruption for Bandundu.

Djoué - Imported to the UK around 1982.

Djoué I took about 1982.

This form distributed as Dejue in the BKA 1993/94.

Kenge - Z 82/18. Thick yellow banding in submarginal pectoral, ventral, anal & lower caudal fins.

Z18 / 82 Kenge Wild male. near to Wamba River, Democratic Republic of Congo. There are 10 different villages with this name in this country.
Photo courtesy of Ed Pürzl

Photo courtesy of Ed Pürzl

Biotope near Kenge, Zaire, collecting place of A. cognatum Z 18 / 82.
Photo: Courtesy of Ed Pürzl.

Kimuenza - When distributed in the UK the location was corrupted to Kimwenza.
Collected in 1980 by Hofmann 25 km south of Kinshasa. These have been recorded & preserved by Tonnie Woeltjes at 73mm.

Kimwenza (taken early 1980's)

Kimwenza (taken early 1980's)

Kinshasa http://www.findfish.nl/vispages/vispagendv/aph cognatum kinshasa 91.htm Japan site
This location also collected by Geoff Wood some 10 km from Kinshasa town centre. The stream was a chance finding, difficult to see due to thick vegetation surrounding it. The water was read as being pH 6·4 & 25°C. This high temperature was read at the peak of the 'hot' season.
Geoff commented in BKA newsletter No. 129, May 1976 that this sp. outnumbered other sp. in the stream namely E.chevalieri, Ctenopoma sp, Synodontis sp. all of which were thought to prey on A.christyi young.“

Found in commercial import from Kinshasa 2000

TAAG 2000/1. Code refers to my initials & Alan Green who found them in a Kinshasa import.

We distributed this wild fish as Aphyosemion sp. XYZ at the 2004 BKA convention & most probably represents A.cognatum. Commercial import from Kinshasa.
Photo courtesy of Ian Sainthouse.

Kinsuka - Situated 2 km from the Congo-Zaire River approximately at the Kinsuka Falls. The second population also distributed as Kinshasa. A fish known as A.cognatum Kinshasa circulated for some years in the early 1980's but many people consider the collection point to have been nearer Kinsuka. In either case the original fish were caught by Wood in the mid 1970's. These fish were brought to the UK. Three months later he returned to the collection site but found that the area had been bulldozed & the habitat destroyed.

Kinsuka



Kinsuka

Kinsuka. Photo courtesy of Maurice Chauche & the KCF website.

Kisantu - Originally distributed as A.cognatum - decorsei but this was soon amended to A.cognatum Kisantu. This proved to be the most difficult population to breed but it did survive in captivity for many years. This collection was collected in the Botanical Gardens at Kisantu close to the Inkisi River.
The fish were collected from a ditch 2 metres wide & 30 cm deep. Although this biotope was covered by large trees areas were exposed to direct sunlight which gave rise to thick aquatic plant growth. Geoff Wood commented that the water was clear & unpolluted. On numerous visits to this location no other fish sp. could be observed.
This population was noted to have a flared caudal fin which had short extensions. Also spawnings produced a great degree of colour variation in males.
In the early 1970's Geoff Wood collected many populations, which were sent to the UK, 2 of these being assigned the same population name - Kinsuka & Kisantu.

Old black & white of the original Geoff Wood collection at Kisantu.
Photo provided by Ian Sainthouse

Old photo from the '70's by Mel Addicott

Kisantu male. This is a slide of the first collection to arrive in the UK. Not sure who sent this but I'm pretty sure it should be credited to Ian Sainthouse.

Kwambila - Collected by W.Wachters in 1979 in a small stream behind the Kinshasa stadium (some reports state Riding School). Blue margins in this collection are reportedly missing.

Kwambila
Photo courtesy of Ed Pürzl

Lake Fwa - Collected originally by Heiko Bleher in 1987.

A.sp.Lake Fwa
Photo courtesy of Pat Rimmer

Lutendele - One of 2 populations distributed as A.cognatum Kinshasa. A population of this name was known to have been in circulation around 1978. It was noted that the amount of red pigmentation varied where some individuals were very red while others had almost no red at all.
Collected by Geoff Wood 1974 / 75 in a small slow flowing stream which had many pools & offshoots made by the villagers. This was accessed at the point where a bridge crossed the stream. The village was accessed by a dirt track leading from the Zaire River & about 4-5 km from the river roughly midway from Kinshasa to the Kinsuka Falls.
There was moderate overhead cover but in places the stream was open to direct sunlight. There was little in the way of aquatic vegetation. The edges of the pools contained grasses & thick green algae. The water was slightly coloured with a sandy bottom. Water temperature 24°C, pH 6·8.
Other sp. found in this location included small crabs, shrimps, large tadpoles & a small cichlid reported to breath air.

 

 

  


Madimba - Collected by W.Wachters in 1979. Introduced to the BKA in 1980 by SIC where they were distributed as Aphyosemion sp. Madimba..

Madimba taken around 1980.
Photo courtesy of Ed Pürzl

Madimba - Early 1980's import

I took this early 1980's & think it was the fish to the left a little older.


Ma'Vallee - Collected by Geoff Wood. His 4th population collected in 1975. Situated to the east of the Kinshasa - Kisantu road some 25 km from Kinshasa. This is thought to be close to the collection point of the Kimwenza population.

 

 

  

Mbamou Island - A large island situated in the Pool Malebo.

 

 

  

Mbanza Ngungu -

Mbanza Ngungu. Wild male.
Photo courtesy of Ed Pürzl.

Mbanza Ngungu. Wild females.
Photo courtesy of Ed Pürzl.

N'Galiema & Maindombe River were commercial imports into the USA in 2003.

N'galiema
Commercial import to the USA in 2003.
Photo courtesy of Peter Tirbak.

 

N'galiema
Photo courtesy of Keiichi Moriya

 

Maindombe
Commercial import to the USA in 2003.
Photo courtesy of Peter Tirbak.

Z82 / 2 See article on breeding in BKA Killi-News No.296 (May 1990).

Z82 / 2. Photo courtesy of Maurice Chauche
& the KCF website.

 

Z 82 / 2 . Photo: Monty Lehmann

Miscellaneous Photos

CI 11 - Commercial shipment to the USA probably by Aquatic Clarity.
Photo courtesy of Jeremy Basch & Jeff Michels

H1. Photo courtesy of Maurice Chauche & the KCF website.

Z22/82 Pool Malebo. Wild male
Photo courtesy of Ed Pürzl.

Aphyosemion cognatum which was in the US
during 1973 -74, it was a bold large fish............
Photo courtesy of Tony Terceira.

A.cognatum Photo courtesy of Ed Pürzl.

Blue . Photo: Monty Lehmann

Z23 / 82 Pool Malebo. Wild male
Photo courtesy of Ed Pürzl.

Z23 / 82 Pool Malebo. Wild female
Photo courtesy of Ed Pürzl.

A.cognatum Photo courtesy of Ed Pürzl.

91/2 (RPC & Z codes were collected in 1991, unknown which one this belongs to)

 

Wild male imported to the USA 2005 collected at Kinsuka. This was labelled CI 05.
Photo courtesy of Tony Terceira.

 
Type Locality

Described from material taken from a commercial shipment sent to Zierfish Import und Exportfirma Hartel of Dresden in 1950. The precise area of collection is unknown although it is presumed to be in the area of Leopoldville (now Kinshasa), Zaire.

Distribution

Huber & Scheel thought in 1981 that the distribution of this sp. was restricted to the surroundings of Kinshasa.

The exact area of distribution is still confused. Many sp. of Aphyosemion from Zaire are extremely close in terms of colouration. The areas inhabited are often flooded or marshy which makes distribution & intermingling of various sp. very easy. It is certain however that cognatum are distributed on the southern banks of the Zaire River around Kinshasa & areas to the south.

The Zaire River drainage south & east of Kinshasa & southern Congo, the lower Kasai River & Pool Malebo are all areas known to contain the species.

Habitat

Shallow areas of streams, pools & swamps in rainforest.

Biotope of A.cognatum Z2 / 82 near Mbanza Ngungu, Zaire.
Photo: Courtesy of Ed Pürzl.

Biotope in Pool Malebo, Zaire, collecting place of A.cognatum Z 22 / 82.
Photo: Courtesy of Ed Pürzl.

Distinguishing Characteristics The elegans group is one of the most difficult to seperate. The Zaire basin is one big melting pot of convergent species. A.cognatum is generally (but not in every case) seperated by the outer margin of the upper caudal fin which shows a pale blue strip. I stress that this is not a 100% measure of seperating the species but is a good indicator to begin identification.
Females hold the key in seperating cognatum (from christyi at least). When viewed from above the edges of the scales can be seen to have a dark edging. In christyi this is absent. We used this method to seperate a wild imported bag out & all pairs bred true so the method works. An excellant photo portraying these differences can be found on page 170 of ROTOW 1.
Colour/Pattern Variability High.
History

As mentioned in the type locality section, this sp. was found in a commercial shipment to Germany via the the Dutch importer 'Aquarium Hamburg' presumeably from Leopoldville (Kinshasa) by Meinken in 1950. This shipment also contained a fish referred to as 'Aphyosemion singa'. In 1954 Aquarium Hamburg had more A.cognatum in & some of these were bought by Scheel.
Hoedeman reported Timmerman maintained them.

In 1959 further specimens were collected from the Ndjili River & the Binza River near Stanley Pool.

Fred Wright (a former BKA Technical Editor) reported receiving them in the late summer of 1954 from a retail outlet in Redhill, Surrey. These were reportedly similar to the Aquarium Hamburg form. It is quite possible given the dates that this retailer had stock from Aquarium Hamburg.

Confusion started between this sp. & A.christyi from Meinken's description due to a lack of information concerning seperating these species.

Meinken's drawing taken from the original description

I have found with wild imports, putting females in a clear plastic tank & looking down at a certain angle shows A.cognatum sp. to have dark edges to the scales whereas A.christyi are clear. I tested this out & fish thus seperated bred true with males found in the same shipment. Scheel discovered this but it's one of those things you have to go a bit further to discover. Check out the photo on page 170 ROTOW 1 to see how we sorted this out. This book contains a lot of information but you do need to put a little more effort in to realise Scheel's work.

David Sale of the BKA imported this sp. in 1968.

BKA Species control imported 8 different pairs from the USA pre-1973 but these were identified as A.christyi or hybrids thereof.

In the early 1970's Geoff Wood collected 4 populations, 3 of which were sent to the UK, 2 of these being assigned the same population name. Kisantu Originally distributed as A.cognatum - Decorsei but this was soon amended to A.cognatum Kisantu. This proved to be the most difficult population to breed but it did survive in captivity for many years.Lutendele A small village on a dirt track leading from the Congo-Zaire River, 4-5 km from the river roughly midway from Kinshasa to the Kinsuka Falls. One of 2 populations distributed as A.cognatum Kinshasa. A population of this name was known to have been in circulation around 1978. It was noted that the amount of red pigmentation varied where some individuals were very red while others had almost no red at all.Kinsuka Situated 2 km from the Congo-Zaire River approximately at the Kinsuka Falls. The second population also distributed as Kinshasa. A fish known as A.cognatum Kinshasa circulated for some years in the early 1980's but many people consider the collection point to have been nearer Kinsuka. In either case the original fish were caught by Wood in the mid 1970's. These fish were brought to the UK. Three months later he returned to the collection site but found that the area had been bulldozed & the habitat destroyed.Ma'Vallee Situated to the east of the Kinshasa - Kisantu road 25 km from Kinshasa. The population not received from these collections came from Ma'Vallee which is situated to the east of the Kinshasa - Kisantu road some 25 km from Kinshasa. This is thought to be close to the collection point of the Kimwenza population.

Line drawings of Kinshasa & Madimba populations as shown in BKA Killi-News No.126, Feb.1976. The Madimba shown on the right was drawn from the original collection which survived in the UK until the mid '80's. The left hand drawing of the Kinshasa population was maintained in the UK in 1968/69. Artist unknown (possibly Fred Wright).

This photo by Fred Wright labelled 'Yellow phenotype'.
Photo in BKA Killinews July 1993

In May 1980 BKA Species Import distributed 2 new forms of the elegans group labelled A.sp.Kwambila & A.sp.Madimba. Both are pictured in this species pages from photographs taken a little later. Both are A.cognatum populations.
Breeding Notes

Geoff Wood remarked in BKA newsletter No. 114, February 1975 that seperation & conditioning on live foods increases egg production. Also, he noted that this sp. will eat their eggs.

I have maintained & spawned 6 populations - Kinsuka, Kinshasa, Madimba, Kimwenza, Djoue, & Z82/2. By far the easiest to spawn was the Madimba population which layed eggs in both top & bottom mops. These eggs took the usual 2-3 weeks to hatch in water. The newly hatched fry seem to do best if fed on larger infusorians for the first day or two graduating on to newly hatched brine shrimp & microworm.

I have grown young fish on in cool water tanks of about 65-70'F but the growth rate is very slow.

Diameter of Egg 1.3mm
Remarks

Apart from commercial imports from Kinshasa this sp. has not been collected by hobbyists since 1991. Despite numerous colourful photographs in books & magazines etc they still seem to be low in popularity amongst killie keepers.
The Madimba population is interesting as I tried on numerous occaisions to send eggs to the States but they always arrived DOA.
That said, they can still be found rarely from time to time. I personally believe they will make a come back in future years.
Sterba in Freshwater Fishes considered their best breeding season was the spring. Young were found to hatch in 12-16 days & were noticed to be very dark in colour.

Further information may be found at :

Catching, Maintenance and Breeding of Killies in Zaire. Wood G. BKA Killi-News No.114. Feb. 1975. Page 1-4.
Letter from Fred Wright. BKA Killi-News No.126. Feb 1976. Page 4-6.
The Kinshasa christyi. Observations for Comment!. Molloy G. BKA Killi-News No. 128. April 1976. Page 3-4.
The Aquarist. Two Fishes of the Genus Aphyosemion. Meinken H. February 1952.