Fundulopanchax lacustris (Radda 1974)

Lake Ejagham. Photo courtesy of Ed Pürzl.

Meaning of Name

After lacustris meaning to come from the lake (Ejagham).

First Description

Radda A.C. 1974 (Aphyosemion gardneri lacustre).

Studien zur Cytogenetik, Taxonomie und Verbreitung der 'Gardneri-Gruppe' der Gattung Aphyosemion (Osteichthyes: Cyprinodontidae) aus dem südlichen Westkamerun.

Jahrbuch des Naturhistorisches Museum der Stadt Bern 5: p 4-6. figure 1B, 3.

Size

54 mm (according to first description).

Meristics

D = 15-16, A = 15-17, D/A = +3-4, ll = 31-32 +2-3 (Radda 1974)

Karyotype
  • Male 2n = 37 (Radda 1974)
  • Female 2n = 39 (Radda 1974)
Sub-Genus

Paraphyosemion

Group

gardneri

Synonyms
  • Aphyosemion gardneri subspecies No.2 Radda 1973
  • Aphyosemion gardneri lacustre Wright 1973 (nomen nudum)
  • Aphyosemion gardneri lacustre Radda 1974
  • Aphyosemion gardneri lacustre Langton (ex Radda), 1974
  • Aphyosemion obuduense lacustre Kottelat 1976
  • Aphyosemion lacustre Huber 1977
  • Fundulopanchax gardneri lacustris Lazara 1984
  • Aphyosemion (Paraphyosemion) gardneri lacustre Huber 1994
  • Aphyosemion gardneri (Cameroon). (From a BKA I/P).
  • Fundulopanchax gardneri lacustris (Radda 1974)
Populations
  • Lake Ejagham
  • C89 / 5 - Lake Ejagham, stream outlet
  • Akaram
  • Akwen (?)
  • Eyoumojok (?). (Corrupted spellings include Eyomojok, Eymojok & Ejomocock as seen in AKA Killie Notes August 1971)
  • HAH 98

The populations -
1 - Eyumojok is not generally put in lacustris but this location is only a few kilometres from Lake Ejagham & on the same outlet stream where Radda's original collection & C89/5 were made. I tentatively add it here.
2 - Akwen - Although Akaram is generally accepted as belonging to lacustris some authors have reservations with Akwen. Collier in his DNA work puts Akwen & Akaram as belonging to the 'lacustris branch'.

All populations listed here are in a small nest of locations within the Munaya drainage.

Lake Ejagham - Lake Ejagham is situated just south of Eymojok. It is treated by local peoples as a sacred lake supposed to be haunted by the ghosts of past ancestors. It lies at the centre of 13 salt springs. Ejagham is split into 3 words - “Ekub” (a whole or parcel), “Ejag” (is split or broken), ‘ Haam” (is infinite or without end). Basically refers to a splitting of the local tribe which is striving for reunification.
Reportedly a crater caused by a meteorite but more likely formed by glacier action many years ago. Also called a 'solution lake' made up from groundwater. This is not a volcanicly formed lake. Size is about 1 km in diameter & 18 metres deep. The lake has no inflow but a single outflow into the Manaya River which is part of the Cross River drainage. The Manaya has a waterfall making it impossible for fish to migrate into the lake from this water course.
Rainfall from May - August, tailing off in September. A dry period from October to April causes outlying pools to dry up. This is a 7 month dry period.
Collected by A.C.Radda in 1970 in drying pools in an outlet from Lake Ejagham.
Collected by Wolfgang Eberl, Oliver Legros & Bas Vlijm, July 1989 ( C 89 / 5 ). This was a small stream (the only outlet from the lake). Also seen in the stream Cichlids & barbs. An hours fishing yielded 10 pairs of 'Aphyosemion' identified as lacustre by Bas Vlijm.
Pools prone to drying out formed by outlet streams from the Lake.
Other fish known to be collected commercially from the lake for the hobby include - Tilapia 'Little Black', Tilapia 'Jewel'.
Blue phase. Variable in spots on body & submarginal bands in unpaired fins. Most uniform characteristic appears to be the dorsal fin, having a pale blue marginal band with a red submarginal band but this is not seem on all individuals.

Lake Ejagham. Photo courtesy of Ed Pürzl.

Photo courtesy of Tony Terceira

 

C 89 / 5 - Collected by Wolfgang Eberl, Oliver Legros & Bas Vlijm, July 1989 in a stream found by walking through an experimental plantation & along a hard to follow trail for 500 metres. Ten pairs of young fish were collected. Other fish found were cichlids & barbs.

C 89 / 5 - Lake Ejagham
Photo taken by kind permission from Werner Eigelshofen's site.

   

HAH 98 - Lake Ejagham

HAH 98 - Lake Ejagham
Photo courtesy of Tony Terceira

    

Radda's 1970's Collections - These photos represent Radda's original fish. Few & small spots, blue phase & a distinctive anal fin with a dark red outer margin.

Lake Ejagham. Photo courtesy of Ed Pürzl.

Lake Ejagham. Photo courtesy of Ed Pürzl.

Lake Ejagham. Photo courtesy of Ed Pürzl.

This was a fish I kept in the early 1980's but proved difficult to breed. It may be a decendant of Radda's collection in 1970 as it predates the C89 trip.

  

This photo taken by Bob Heap about 1976 showing the form introduced into the BKA as Aphyosemion gardneri 'Cameroon'
This may be a descendant of Radda's collection in 1970.
BKA Photo.

Type Locality

An outlet of Lake Ejagham near Eyoumojok in the Ossidinge area.They were found in small pools of a drying tributary.

Distribution

Restricted to the area of Lake Ejagham, western Cameroon ???.

Click link to map of gardneri distribution. This comprises all populations I can find on maps. You can zoom in but markers are not accurate to the exact collection spot, just the area which builds up a picture of distribution. map

The single stream from Lake Ejagham drains towards Eyumojok. Around here maps do not show the stream continuing far outside the village. Eyumojok is likely to drain into the Munaya river which is where Akaram is located (Akwen also drains into this river). Akaram has been distributed as lacustris & it may be that Lake Ejagham, Eyumojok, Akaram & possibly Akwen are all part of lacustris.
These locations represent the known locations of gardneri which drain into the Munaya River.

Habitat

Small pools, streams & brooks originating from a single outlet from Lake Ejagham. Some of these pools are most likely to be seasonal.
Wildekamp in 'World of Killies' remarked that they were also found 'in pools & shallows along the banks of the lake itself'.

Distinguishing Characteristics Easily distinguished from other gardneri forms. The basic body colouration is green. The red spots on the body are small & are arranged in broken lines. This is perhaps the least colourful of all gardneri forms.
In Wildekamp's book 'Wold of Killies' he remarked the top caudal extension was longer than the lower extension.
Colour/Pattern Variability Not as high as some of the other gardneri subspecies but their is variability between different collection dates.
Scheel in ROTOW II described the anal fin as being greenish yellow to orange which may exhibit a row of small red spots in the basal area.
The anal fin seems to be a strong identifier with an outer marginal band of dark red. Some fish also exhibit a row of small red spots horizontally midway through this fin.
History

Found in 1970 by A.C.Radda & Walter Haefelin in pools of a drying outlet of Lake Ejagham. They also collected at Eyumojok.
Also collected by Wolfgang Eberl, Oliver Legros & Bas Vlijm in July 1989. Collection C89.

Breeding Notes

This is perhaps the most difficult of all the gardneri sub-species to breed. Some reports suggest that this type is best spawned in cool water while others suggest that they only spawn at certain times of the year. I must admit defeat with this one, having tried many years ago. All attempts to spawn them ended in defeat & I decided to pass them on to a fellow killie keeper to see if they would do better in his water.
Reports suggest that two forms have been known to be in the hobby, a blue form which was found to be easier to breed, & a green form which proved more difficult. The form circulating in the BKA during the early '80's did have a green body colouration as can be seen in the photo at the top of this page.

They are regarded as more of an annual than most 'gardneri' with eggs taking 4 weeks of semi-dry storage to hatch. Fred Wright observed that most of those hatching in this period were observed to be males in BKA newsletter No.100, December 1973. It was noted that if this peat was left submerged in water for a further period the hatching fry turned out to be mostly females.

Alan Green bred this subsp. in the '80's in 2' (60 cm) deep tanks but had few eggs. Water temperature approx. 73°F.

Diameter of Egg 1.3 / 1·4mm
Remarks

Lake Ejagham is an isolated biotope with no feeder streams & only one output stream. This stream is where Radda & the C89 collections were made. It's interesting as the Radda collections of 1970 appear different, being very bland looking with little colour & a green overcast. The C89 collection seems more colourful with more red spots.

The closest village to the lake is Eyumojok. From here the road east passes through the collection sites from Akwen & Akaram.

I think lacustris is an interesting sub species. Generally thought of as just coming from an outlet from Lake Ejagham. The outer marginal dark red band in the anal fin is also present in the Eyumojok population which is further downstream in the stream coming from the lake.
The populations from Akwen & Akaram also had this band when they first came into the UK but over generations of breeding this band has not been seen in photographs. Also, Akwen & Akaram are drained from a different stream source.