REVIEW COASTAL PLAIN WEST AFRICA

 

 

A REVIEW OF THE CYPRINODONT FAUNA OF THE COASTAL PLAIN IN RIO MUNI, GABON, CONGO, CABINDA AND ZAÏRE

 

With taxonomic Shifts in Aphyosemion, Epiplatys and West African Procatopodins.

 

By Dr. Jean H. HUBER*

 

* Laboratoire d'Ichtyologie, Muséum national d'Histoire naturelle, 43 rue Cuvier, 75231 Paris Cedex 05, France.

A BKA publication, NOVEMBER 1981

SYNOPSIS

 

Having presented the biogeography, ecology and hydrography of the studied area, the author reviews its cyprinodont fauna, presented by phylogenetic groups.

 

Systematic moves are proposed:

* Rivulins

- Aphyosemion simulans is a junior synonym of A. microphtalmum

- Panchax escherichi is checked to be a junior synonym of striatum after the study of the types.

- A. marginatum is proposed as having full species status, but further studies are demanded.

- Epiplatys macrostigma, ansorgii and ornatus are all junior synonyms of Ep. singa

 

* Procatopodins

A different taxonomy is presented, giving Clausen's characters a descriptive interest, only

- Aplocheilichthys is proposed to be restricted to the coastal Western Africa fish: spilauchen, as Pantanodon is endemic to the Eastern African coast.

- Micropanchax becomes the basic genus for non Procatopus -like species

- Laciris new genus is proposed for pelagicus, a lacustrine fish as Lamprichthys for tanganicanus

- Aply. tschiloangensis is a junior synonym of spilauchen after the study of the types

- Mic. (Poropanchax) keilhacki may be a senior synonym of macrophthalmus for morphological and geographical reasons

- Plataplochilus is a junior synonym of Procatopus, but the sub-genus level might be maintained

- Proc. chalcopyrus and mimus are junior synonyms of ngaensis

- Proc. pulcher is a junior synonym of miltotaenia

- Proc. loemensis and micrurus are junior synonyms of cabindae

- In a subsequent paper it is shown that Micropanchax stictopleuron is a senior synonym of silvestris.

 

 

A. INTRODUCTION

 

The Cyprinodont fauna of the coastal plain in Rio Muni (officially Mbini or Equatorial Guinea), Gabon, Congo, Cabinda and Zaire is studied here mainly for 3 reasons:

1. No comprehensive work has been published so far

2. Instead, a lot of collecting trips have been organised

3. Our field of knowledge is reasonably complete, but the published work is scattered.

 

10 recent collecting trips have occurred in the last 18 years from Rio Muni to Zaire:

- Roman (1966, 1968) and Scheel (1969) in Rio Muni; Lambert (1962, 1964), Huber and Radda (1976), Huber (1979) and Pap (1980) in Gabon; Stauch (1963), Lambert (1964), Buytaert and Wachters (1978), Huber (1978), Agnèse (1980) in Congo, Cabinda.

- Personally I have visited Congo and Gabon and reviewed some of the preserved material of Paris, Tervuren, London and Berlin Museums and I wish to thank the authorities for their help, especially Prof. Daget, Prof. Van den Audenaerde, Dr. Chambers and Dr. Paepke. In addition, I give my friendly thanks to Ruud Wildekamp for his drawings and for having read the manuscript, together with Lothar Seegers.

 

The studied area is very interesting because the four main groups of non annual west African Cyprinodonts are present; 7 lines of evolution are represented in the genera Aphyosemion, Epiplatys, Procatopus and Micropanchax. This area is also very interesting because its fauna is specific: if the northern part of Rio Muni is excluded, i.e. North of the Benito River, then the whole fauna, living therein, is not found elsewhere; in other words, despite the absence of geographical barriers, the influence of the Cameroon coastal fauna and Congo basin fauna is poor, and that of Angola is probably nil.

 

B. BIOGEOGRAPHICAL CONDITIONS

 

The studied area is very homogeneous from a geographic point of view:

- West, it is limited by the Atlantic Ocean

- East, it is bordered by the sharp rise of the Inland plateau

- North of the Rio Benito, no geographical barrier exists but the fauna is different and, according to Scheel, the cyprinodont fauna becomes rare until the Kribi latitude, for some unknown reason

- South, it is bordered by the large Zaire River near its estuary, and by the Angolan hills.

 

There are two exceptions in this scheme : the possible penetration of the inland fauna in Rio Muni (A. cameronense) and in the Niari-Zaire Valleys (A. elegans group, Ep. multifasciatus group).

The studied area forms a "corridor" 1000 Km long and 80-150 Km wide.

Soils are sediments near many river systems; North to South are reported the Rio Benito, Komo, Ogooué, Ngounié-Nyanga, Kouilou and Zaire systems.

Soils are also from the basement complex in the Mayombé hills in Southern Gabon and Congo.

Primary forest covers more than 80% of the area, the rest being occupied by a band of forested savannah between the Mayombé hills and the Inland plateau.

Therefore, the area is also homogeneous from a biological point of view and three species live in the whole range: A. australe, Ep. singa and Aply. spilauchen.

Frontiers between species exist however and the reasons for their occurrence are unknown to us.

 

C. REVIEW OF THE CYPRINODONT FAUNA

 

This review is presented in a uniform format to help a systematic reading.

Species are grouped in superspecies, then in genera, beginning with the first described in each superspecies.

The following items are discussed in order: species name, reference, origin of types and their collector if different from describer, meaning of the name, usual synonyms, list of recent collecting places in the studied area, followed by K (for kept) if the population has been maintained in Aquarium, description of the key features compared to other members of the superspecies, ecology, distribution, and remarks concerning its validity and the future studies needed.

 

1. THE RIVULINS

 

Rivulins are the most important and the most widely represented group of Cyprinodont.

In West Africa, they are represented by two main groups, Epiplatys and Aphyosemion, and by some relict groups such as Diapteron or Adamas. Those fishes have an elongate body, not or little compressed laterally, a small size and a strong sexual dichromatism. The morphological variability is weak within a species, except in annuals, and little allometry is observed during growth. Fins are brilliantly coloured in males and the pectorals are inserted in the inferior part of the body. Micro-morphological criteria such as ctenoidy, frontal neuromasts, and head pores are useful at the species level, not to define evolutionary groups. Instead, karyotypes, geographical origin, morphometry (D, A, D/A), and egg membrane structure are critical to build superspecies.

The above list is not intended to define thoroughly the Rivulins but to differentiate them from the Procatopodins.

 

1.1 The Genus Aphyosemion Myers, 1924

 

The genus Aphyosemion is well represented in the studied area: the fishes are always very abundant, but the number of superspecies concerned is small.

Only one endemic superspecies covers the whole range: striatum and two others which are in a recessive position: the subgenus Chromaphyosemion that has not managed to cross the Komo estuary and australe /ahli that are restricted to a narrow littoral band.

There is no trace of annual species though some biotopes appear suitable for them.

The speciation is limited to the striatum superspecies and thus ranks far behind that of Cameroon or Nigeria. However, the occurrence of a dense primary forest, of a sharp cut between the coastal plain and the inland plateau, and the equatorial climate, has provided with a strong occupation density of the biotopes: Aphyosemion is always abundant in brooks, in contrast to Epiplatys species, Procatopodins and other fishes.

Because of the absence of ecological barriers the three superspecies are found sympatric in their common range, i.e. Southern Rio Muni and Northern Gabon. It appears interesting to note that, in that case, those Aphyosemion species develop distinctive patterns in the choice of the niche (as suggested by Scheel 1974) in behaviour and most probably in feeding habits (as shown by Brosset in the Ivindo Plateau area): splendopleure and microphtalmum prefer crystal clear waters whereas striatum demands stagnant leafy waters and australe very stagnant raffia swamps (Cap Estérias fauna).

More surprising - and exceptions to the rule. - are the sympatric occurrence of two elements of the same superspecies and the discovery of the inland species cameronense in the Rio Muni plain (see further).

Finally, and probably most important, this area is an excellent example of the distribution and evolution of Aphyosemion.

Superspecies distributions are parallel to the coast, even in the inland plateau (Huber, 1980)

It may be reminded the key rule in Aphyosemion: sympatric occurrence of elements belonging to different superspecies (heteromorphs) and allopatric occurrence of elements of the same superspecies (isomorphs).

 

The various elements of a superspecies tend to be allopatric, replacing each other from the North to the South: e.g. striatum, marginatum, gabunense, exigoideum, primigenium, with the exception of microphtalmum. Ecological or geographical barriers are not present to explain this situation.

 

The case of "Frontier Species" is typical here: the concept of what I call "Frontier species or phenotype" (Huber 1980) seems a key in the evolution of the genus. A frontier species is a biospecies with a restricted distribution, living at the border or at the periphery of its superspecies and thus facing the competitive pressures of the neighbouring superspecies. Many examples can be identified:

-         rectogoense and ogoense (with, in addition, colour convergence) that are the frontier phenotypes of the elegans and ogoense superspecies,

-         mimbon and maculatum, frontier phenotypes of the Southern cameronense superspecies,

-         abacinum and seegersi, frontier phenotypes of the Diapteron superspecies, again with colour convergence, with the neighbouring exiguum superspecies, etc.

 

If the specification of the ecological niche is admitted (see above; Scheel, 1974) then the probability of development of one or two species seems much higher when the two neighbouring superspecies tend to prefer the same ecological niche. The examples above are typical. In the studied area, another similar case occurs: the frontier phenotype, within the same superspecies (see further); however, we must then determine the status level of those special phenotypes.

 

1.1.1 The Subgenus Chromaphyosemion Radda (viz. the bivittatum group).

 

The subgenus Chromaphyosemion is poorly represented in the studied area. Two species, whose status is rather obscure, are identified as aff.: loennbergii and splendopleure.

In Northern Gabon, the representative, namely "splendopleure" is quite rare.

In aquarium conditions these fish from the studied area are difficult to maintain and breed: non annual 2 - 3 weeks incubation time in water.

 

A. (Chrom.) loennbergii (Boulenger, 1903)  1  LOE

 

Fundulus loennbergii Boulenger: Ann Mag. Nat. Hist. (7) 12.

Types from the Kienké river, near Kribi, southern coastal Cameroon - collected by Bates

 

Meaning of the name: dedicated to Lönnberg.

Main synonyms: Fundulus pappenheimi Ahl, 1924 Bipindi, Cameroon

A. (Fundulopanchax) unistrigatus Ahl, 1935 Bipindi (also!), Cameroon

 

List of Recent Localities:

1. Lower Benito, South, Rio Muni, Collected J.J. Scheel, 1968 (K)

2. Upper Ecucu, 36 Km east of Bata, Rio Muni, Collected J.J. Scheel 1968 (K)

 

Key Features

Male with flames in unpaired fins. Two black bands poorly visible.

Karyotype: n = 15; A = 25 to n = 17; A = 25

Meristics: D = 12, A = 12, D/A = + 1

Size: T.L. male, 50 mm, female, 40 mm

 

Ecology: no experience, see splendopleure

 

Distribution and Systematics: According to Scheel (1974), modified by Radda (1975), loennbergii is restricted to the basement complex, South of Nyong River and splendopleure to the sediments.

The band of sediments in N. Cameroon (type area for splendopleure) is however interrupted in South Cameroon and starts again in Rio Muni and Gabon: Drawings of specimens from these two areas seem very different; further studies are required.

On the other hand, the phenotypes in Rio Muni (loennbergii sensu Scheel) and Gabon (splendopleure sensu Radda) are quite similar so that the distinction of the species based on the type of soils of this area might be a purely intellectual construction.

 

A. (Chrom.) splendopleure (Meinken, 1930)  2  SPP

 

Fundulopanchax splendopleuris Meinken: Wochenschr Aquarien und Terrarien Kunde 27, p 17.

Types from Tiko, Cameroon, collected by Griem.

 

Meaning of name: with very beautiful sides (Greek).

Main Synonym: A. bivittatus Roman, 1971.

 

List of Recent Localities.

1. (Tentative) 19 Km and 35 Km East of Bata, Central Rio Muni; coll. Roman, 1968.

2. (Tentative) Between Eban and Macora, Central Rio Muni; coll. Roman

3. Cap Estérias, near Libreville, Northern Gabon; coll. Herzog 1975 (K): identified here as "aff.".

 

Key features:

Male unpaired fins dotted. Two black bands sharply visible on the body.

Karyotype: n = 17, A = 25 to n = 13, A = 22

Meristics: D = 11; A = 13; D/A = +1

Size: T.L: male, 50 mm, female, 40 mm

 

Ecology: likes crystal clear, very gently moving water and hides under water plants (e.g. Anubias), roots or rocks in very shallow parts, Sympatric with striatum near Owando (pers. comm.) Northern Gabon.

 

Distribution: see loennbergii (splendopleure should be restricted to sediments). Roman's specimens are tentatively reported here, because they have been collected near the coast, presumably in an area of sediments.

 

1.1.2 The striatum coastal superspecies

 

The striatum superspecies is the most important in the studied area; it is composed of two elements which may be sympatric:

striatum and allied: marginatum, gabunense, boehmi, exigoideum, and primigenium, from the North to the South,

microphtalmum, present all over the range especially in hilly areas Mayombé (Gabon - Congo) and Crystal Mountains.

 

In aquaria, these species are easy, non annual: 2-3 weeks incubation time in water.

 

Aphyosemion simulans is a junior synonym of A. microphtalmum

 

Two basic elements supported the creation of the taxon simulans in 1976 by Radda and myself:

(1) - 800 Km separated the two known nearest localities of microphtalmum and simulans, the area in between being occupied by primigenium and exigoideum.

(2) - colour pattern of fishes; females: very dotted in Gabon, little dotted in Congo: Males: regularly striated in Gabon, mosaic striated in Congo.

These elements have lost significance since I have discovered new populations in the coastal plain of southern Gabon (loc 204-206) and central Gabon (loc 216) in 1979 when females were variably dotted and a population with a mosaic in males in northern Gabon (loc 221).

Moreover, the karyotypes of the two taxa are not sufficiently different to ascertain cross sterility and truly (Seegers, pers. comm.) the two fishes easily interbreed. One must point out one's mistakes: simulans is without doubt the same species as microphtalmum.

 

A. gabunense and A. exigoideum, examples of the occurrence of frontier species.

 

When one considers the phenotypes of the striatum superspecies, it is interesting to look at striatum and primigenium : same body pattern, analogies in fin pattern (only primigenium shows a closed pattern in the caudal); few or no spots inside the red contour; ctenoid scales on males body and D/A rays number larger. To prevent conflicts, it seems that two frontier phenotypes have developed on one side and the other: north gabunense s.l., south exigoideum. Then gabunense would be the frontier phenotype issued of striatum and exigoideum from primigenium; morphology and colour pattern support this idea and colour patterns of gabunense and exigoideum are very variable.

When one considers the karyotypes of these forms, the basis is confirmed: exigoideum and primigenium show similar karyotypes, very different from the karyotypes of striatum and gabunense which are also similar. These similarities raise the problem of the status of those taxa and obviously crossing experiments are needed.

 

The exceptional case of two sympatric members of the same superspecies: A.striatum and A.microphtalmum.

 

The sympatric occurrence of fishes belonging to several different superspecies is the rule in Aphyosemion (Huber, 1978): isomorphic elements are allopatric (cryptic species of one superspecies), heteromorphic elements are sympatric. Only two exceptions are known so far all along the range:

(1) The sympatric existence of the Diapteron elements in the Ivindo Basin (cyanostictum and georgiae for example) and,

(2) The sympatric existence of microphtalmum and striatum in Northern Gabon (Ioc. 57, 58, 221). But to obey to the natural rule of minimisation of competition between relatives, they have chosen different types of biotypes: when sympatric, microphtalmum is always found in clear open waters, flowing over sands or stone, and striatum in "cloudy" standing waters quietly flowing over dead leaves and mud.

 

A. striatum (Boulenger, 1911)  3  STR

 

Haplochilus striatus Boulenger: Ann Mag. Nat. Hist. 8 (8)

 

Types from the Abanga River, affluent of Ogooué, Northern Gabon collected by Ansorge.

 

Meaning of the name: striated (Latin)

 

Main Synonyms: Panchax escherichi Ahl, 1924

Epiplatys striatus Poll, 1952

Aphyosemion lujae La Corte, 1961

Aphyosemion striatum ogoense Roman, 1972

 

List of Recent Localities:

1. Lambaréné, near the airfield, Northern Gabon, coll. Lambert, 1962

2. Cabo San Juan, Southern Rio Muni, coll. Roman, 1968

3. 14 Kms down the road from Rio Benito to Bitica, coll. Roman, 1968

4. 5 Km Northeast of Libreville Northern Gabon, coll. Herzog and Bochtler, 1972 (K)

5. Cap Estérias, Northern Gabon, coll. Herzog and Bochtler 1972 (K)

6. 5 Kms North of Lambaréné towards Kango, Northern Gabon, Loc 33, coll. Huber and Radda 1976

7. Near Gricole, 118 Km North of Lambaréné, Northern Gabon, Loc 35, coll. Huber and Radda 1976

8. 6 Km South of Kouamé, Northern Gabon, Loc 56/57, coll. Huber, 1976.

9. 2 Kms after Kinguélé crossroads, Northern Gabon, Loc 58, coll. Huber, 1976 (K)

10. 2 Km West of Ntoum, Northern Gabon, Loc 59, coll. Huber, 1976.

11. 1 Km West of Ndjolé, Northern Gabon, Loc 218, coll. Huber, 1979

12. Near Andem, between Libreville and Kango, Northern Gabon, Loc 219, coll. Huber, 1979 (K)

13. 40 Km North of Ntoum, on the road to Cocobeach, Northern Gabon, Loc 231, coll. Huber, 1979

14. 10 Km East of Lambaréné, Northern Gabon, colI. Pap, 1980

 

Key Features:

Male with five rows of longitudinal red lines on blue-green body (sometimes broken, loc 58)

Double red band in D, C and A (typical), interior C dotted Upper filament in C of old male.

The samples reported by Roman (1972) have been reviewed, they belong to striatum.

This is also the case for the types of escherichi, kindly lent to me by the Berliner Museum authorities.

This species is often found sympatric with microphtalmum : youngsters are difficult to separate, females of the latter are somewhat more massive and fin-dotted.

Karyotype: n = 20 A = 35

Meristics: D = 1; A = 13; D/A = +6

Size: TL = 55mm

 

Ecology: Prefers stagnant waters, even. poorly clear (difference with microphtalmum)

 

Distribution: South of Rio Muni and Northern Gabon, seems absent South of Ogooué, where it is replaced by its close relatives exigoideum and primigenium.

Easterly, it climbs the first steps of the plateau (Crystal Mountains, Ndjolé) but fails to invade it.

 

A. microphtalmum Lambert and Géry, 1967  4  MIP

 

Aphyosemion striatum microphtalmum Lambert and Géry: Biol. Gabonica 3(4) 251-315.

Types from 85 Km east of Pointe Noire towards Sounda, Southern Congo.

 

Meaning of the Name: small eye (Greek)

 

Main Synonym: A. simulans Radda and Huber, 1976

 

List of Recent Localities:

1. Type locality, Southern Congo, coll. Lambert, 1962.

2. Road of Sounda, subsidiary of Kouilou River Southern Congo, coll. Stauch, 1963

3. Road of Sounda at Tombo, Southern Congo, coll. Stauch, 1963

4. River Loémé at Las Sarras, Southern Congo, coll. Stauch, 1963

5. South of Tshéla, Lower Congo, Zaire, coll. Lambert, 1970

6. River Tiaba, tributary of Lubuzi Southern Zaire, coll. Lambert, 1970 (K)

7. Chiloango, near the Cabinda - Congo border, coll. Lambert, 1970

8. Between Atogafina and Mala, Crystal Mountains, Northern Congo, coll. Herzog, 1973 (K)

9. Cap Estérias, Loc 1/36, Northern Gabon, coll. Huber and Radda. 1976

10. 6 Km East of Kouamé, Crystal Mountains North Gabon, Loc 57, coll. Huber,1976

11. Road towards Kinguélé, Crystal Mountains, North Gabon, Loc 58, coll. Huber,1976

12. Between Loudima and Loubomo, Southern Congo (RPC 3), coll. Buytaert and Wachters, 1978

13. Forestry Camp near Ngoungi, Southern Congo, loc 180, coll. Huber, 1978.

14. Near Mayumba, Southern Gabon, Loc 204-206, coll. Huber, 1979

15. 50 Km West of Mandji, Central Gabon, Loc 216, coll. Huber, 1979

16. Near Ntoum, 30Km East of Libreville, Northern Gabon, Loc 221, coll. Huber, 1979

17. 19 Km North of Ntoum towards Cocobeach, Northern Gabon, Loc 232, coll. Huber, 1979

 

Key Features:

Male body blue with 4 - 5 red longitudinal lines which can be broken or mosaic. Symmetrical pattern in C, even closed sometimes. No filament in C. White margin in D, C, A. No double band in D or A.

Female, with many spots in Northern Gabon, few or no spots in Congo.

Karyotype: n = 19; A = 38 (type area), n = 20; A = 35 (simulans)

Meristics: D = 11; A = 14; D/A = +6

Size: TL: male, 75-80mm; female, 70 - 75mm. Largest of the group with primigenium.

 

Ecology: prefers crystal clear waters which may be quick flowing, such as hilly brooks. Rarely found among dead leaves as striatum. Very robust and adaptive species.

 

Distribution: very wide; an exception in Aphyosemion: Northern Gabon (perhaps Rio Muni) to Zaire. Climbs easily the first steps of the inland Plateau in Crystal Mountains and coastal hills such as the Mayombé, but surprisingly does not live in the adjacent part of Congo Plateau, where it is replaced by the ogoense superspecies: the thysi component.

 

Note: Those specimens collected by Stauch in Southern Congo were tentatively identified as cameronense in MNHN (Paris Museum), prior to the description of microphtalmum.

 

A. gabunense Radda,1975  5  GAB

 

Aphyosemion gabunense Radda: BKA Separatum : 1-20

Types from south of Lambaréné Northern Gabon, collected by Herzog

 

Meaning of the Name: from Gabon (German spelling)

 

Main synonyms: none

 

List of recent localities:

1. 30 Km Southeast of Lambaréné, Northern Gabon, coll. Herzog, 1973 (K)

2. 43 Km North of Fougamou, Loc 32, Northern Gabon, coll. Huber and Radda, 1976 (K)

 

Key Features:

Male: blue phase, south of the Ogooué River, closed pattern in C, no yellow or white submarginal band in D, C, A as in marginatum. Broad dark red margin in D, C, A. Filaments in Caudal, longer upper than lower.

Karyotype: n = 20

Meristics: D = 11, A = 13, D/A = +6

Size: total length = 55 mm

 

Ecology: fairly typical of primary forest Aphyosemion.

 

Distribution: restricted area between Lambaréné and Fougamou, northern Gabon,

just west of the inland Plateau. Frontier species competing with A. exigoideum.

 

Systematic note: two subspecies have been described by Radda and Huber (1977): marginatum should deserve full status, boehmi further study.

 

A. primigenium Radda and Huber 1977  6  PRI

 

Aphyosemion primigenium Radda and Huber - Cyprinodontiden Studien in Gabun V: Das Tiefland West-Gabuns und die Mayombé-Berge, Aquaria 24: 138-146.

 

Types from the Douano Subsystem of Nyanga, near Banyanga, Southern Gabon.

 

Meaning of the Name: primitive (Latin)

 

Main Synonym: none

 

List of Recent Localities:

1. 20 Km North of Lébamba, Loc. 23, southern Gabon, coll. Huber and Radda, 1976

2. In Lébamba, Loc. 24, coll. Huber and Radda, 1976 (K)

3. In Makaboa, road from N'dendé to Tchibanga, Loc. 25, coll. Huber and Radda, 1976 (K)

4. Near Banyanga, same road, Loc. 27, coll. Huber and Radda, 1976 (K)

5. Near Mouila (?), Loc. 29, coll. Huber and Radda, 1976 (K)

6. Near Ndendé, Loc. 202, coll. Huber, 1979

8. 7 Km East of Lébamba, Southern Gabon, coll. Pap, 1980

 

Key Features:

Male body pattern as in striatum. Double red band in D and A. Closed pattern in C. Few or even no spots in base part of fins. No filament in C. A little larger than striatum.

Ctenoid scales in old specimens.

Karyotype: n = 11; A = 21.

Meristics: D = 12, A = 14, D/A = + 5.

Size: total length, 65-70 mm.

 

Ecology: inhabits two types of biotope: the drying brooks or ponds of the savannah areas around Ndendé and Tchibanga and the quick running forest brooks flowing down the Mayombé hills.

 

Distribution: wide: south of Fougamou and probably in Northern Congo, too; it does not seem to reach the coast where it is replaced by microphtalmum. Easterly climbs the first steps of the inland plateau, near Lébamba but it is replaced by A. joergenscheeli at 250 m height.

 

A. exigoideum Radda and Huber, 1977  7  EXO

 

Aphyosemion exigoideum Radda and Huber - Cyprinodontiden Studien in Gabun V; Das Tiefland West Gabuns and die Mayombé-Berge, Aquaria 24: 141-143.

 

Types from near Fougamou, Northern Gabon Loc 31.

 

Meaning of the Name: little, trifling (Latin)

 

Main Synonym: none

 

Key Features:

Male with marbled body. Closed caudal, Interior of C: blotches. Double bands in D and A . No filament in Caudal.

Karyotype: n = 11; A = 21

Meristics: D = 10; A = 14; D/A = +6

Size: total length, 65-70 mm

 

Ecology: Not well known (the two localities, rivers 10-20 m wide, are not typical of Aphyosemion). Presumably the same as gabunense.

 

Distribution: restricted area south of Fougamou; frontier species competing with A. gabunense; replaced by A. primigenium southerly.

 

Systematic note: its karyotype is very near that of primigenium. For this reason might be an off-shoot. Further studies (collecting, crossing) are needed to estimate the level of separation.

 

A. marginatum, Radda and Huber, 1977  8  MRG

 

Aphyosemion gabunense marginatum: Radda and Huber - Cyprinodontiden Studien in Gabun V: Das Tiefland West Gabun and die Mayombé-Berge. Aquaria 24: 143-145.

 

Types from a brook 9 Km southwest of Bifoun, Northern Gabon.

 

Meaning of the Name: ornated by marginal bands (Latin)

 

List of Recent Localities:

1. 9 Km southwest Bifoun, north of the Ogooué river, Loc. 34, coll. Huber and Radda, 1976 (K) and Pap, 1980 (K)

 

Key Features:

Male with marginal black bands in D, C, A. Yellow phase. Open Caudal. Short filaments in C.

Karyotype: n= 18; A = 38

Meristics: D = 11; A = 14; D/A = +6

Size: total length, 55 mm

 

Ecology: in this area of secondary forest, brooks are nearly dried up at the end of the dry season. The type locality was not protected from the sun: water temperature 24.8°C, conductivity 120 µs20.

 

Distribution: unknown: probably small although no barrier seems to exist; marginatum faces the competition of striatum, well distributed.

 

Systematic Note: although marginatum seems strongly related to gabunense it differs by karyotype, colour pattern and its occurrence north of the Ogooué river, which, by its width in this area, may be a full barrier; thus it should deserve a full status when crossing experiments are undertaken.

 

A. gabunense boehmi Radda and Huber, 1977  9  BOE

 

A. gabunense boehmi Radda and Huber: Cyprinodontiden Studien in Gabun V: Das Tiefland West Gabuns und die Mayombé-Berge, Aquaria 24: 145-147.

 

Types from a brook down the road from Bigouénia to Mora, northern Gabon.

 

Meaning of the Name: dedicated to Otto Böhm, Vienna

 

Main Synonym: none

 

List of Recent Localities:

1. Road Bigouénia to Mora, north of Fougamou, Northern Gabon, coll. Bochtler and Gaspers, 1976 (K)

 

Key Features:

Male, with asymmetrical pattern in caudal bands, rows of red points regularly disposed on body. Long filament in upper C.

Karyotype: unknown, presently

Meristics: D = 11, A = 14; D/A = + 6

Size: total length, 55-60 mm

 

Ecology: fairly typical of Aphyosemion

 

Distribution: restricted to a small area north of Fougamou, probably competing with exigoideum.

 

Systematic Note: if the asymmetrical pattern is found stable in a certain geographic area and no intermediates with gabunense reported, then boehmi may deserve full species status. New collecting places are strongly needed. A key element may be the sympatric occurrence of Ep. berkenkampi whereas some kilometres to the north, A. gabunense, typical form, is found sympatric with Ep. sexfasciatus, Loc 32.

 

1.1.3 The Calliurum superspecies

 

The calliurum superspecies is represented by two species in the studied area: ahli in Rio Muni, australe in Gabon and southern. Their distinction has been established by Scheel (1974) on the basis of their karyotype. Up to now, ahli was considered to be the fasciated component of the superspecies but the Mayumba australe also shows this type of pattern.

 

In Aquaria, these fish vary from very easy to difficult, according to the population; F1 and F2 seem more resistant and co-operative; non-annual 2-3 weeks incubation time in water.

 

In 1978, I reported the occurrence of australe in Cap Lopez, which was considered the first reported spot of that species in 1913 but had never been proved. Now, with the review of the Stauch collections in M.N.H.N. (Paris Museum) and the recent reports from Congo, it appears that the distribution of australe extends far to the south until the Zaire river. It is remarkable to note how the distributions of australe and microphtalmum match: several times they have been reported sympatric, but microphtalmum may occupy the whole plain whereas australe is restricted to the littoral band without a rational reason.

Finally, it would be informative to know if the two forms have managed to cross the Zaire river and invade the north of Angola.

 

A. australe (Rachow, 1921)  10  AUS

 

Haplochilus calliurus var. australis Rachow

Bibl. Aquar. Terr. Fr. (16). Types presumably from "Kap Lopez" i.e. Port Gentil, northern Gabon.

 

Meaning of the Name: southern

 

Main Synonyms: Panchax polychromus Ahl, 1924

A. australe "hjerresensii" Meinken, 1953 (golden variety, nomen nudum)

 

List of Recent Localities:

1. Djembo, southern Congo, coll. Stauch, 1962

2. Yangala, southern Congo, coll. Stauch, 1962

3. Lake Youbi, southern Congo, Coll. Stauch, 1962

4. Labanzi, southern Congo, coll. Stauch, 1963

5. Yanga, southern Congo, coll. Stauch, 1963

6. Sandra, southern Congo, coll. Stauch, 1963

7. Libreville, Cap Estérias northern Gabon, coll. Arnoult and Sabatier, 1973, coll. Herzog, 1973 and (Loc. 2, 36) coll. Huber and Radda 1976.(K)

8. Near Port Gentil, Cap Lopez, coll. Mathieu, 1977

9. 10 km eats of Pointe Noire (RPC 2), south Congo, coll. Buytaert and Wachters 1978

10. Near Mayumba, southern Gabon, coll. Huber, 1979 (K)

11. Between Bas Kouilou and Madingo-Kayes, southern Congo, coll. Agnèse, 1980

 

Key Features:

Male body pattern variable: irregular spots (type), irregular lines (Cap Estérias), vertical blotches (Mayumba). Long filaments in C. Yellow margin in C but not in D or A. Red submargin.

Karyotype: from n = 17 A = 19 to n = 15 A = 19

Meristics: D = 10; A = 15; D/A = +7

Size: male, 60 mm, female, 55 mm

 

Ecology: prefers small stagnant ponds rather than brooks; only pure soft water; hides among dead leaves or Raffias; when collected show typical behaviour of jumping out everywhere.

 

Distribution: very wide: from northern Gabon to southern Congo and most probably until the northern bank of the Zaire river. However, australe is restricted to the marshy areas near the coast: the distribution breadth should not exceed 20 Km; it does not occur easterly, in contrast to the sympatric striatum superspecies.

 

Note: those specimens collected by Stauch in southern Congo, were labelled as cameronense in M.N.H.N. (Paris Museum).

 

A. ahli Myers, 1933  11  AHL

 

Aphyosemion calliurum ahli Myers: Copeia (nom. nov.)

First description: Panchax (Aphyosemion) calliurus var. coerulea Meinken - Kalender Aqu. und Terr. Frde: 66.

Types from "Tropical West Africa"; re-described by Scheel (1968) from an East Cameroon area between Mbongé and Kribi.

 

Meaning of the Name: dedicated to E. Ahl

 

Main Synonyms: Panchax (Aphyosemion) calliurus var. coerulea Meinken, 1932 (pre-occupied name).

 

List of Recent Localities:

1. Bata, northern Rio Muni, coll. Roman, 1966

2. 19 km off Bata towards Machinda, northern Rio Muni, coll. Roman, 1966

3. Between Ebam and Macora, Rio Muni, coll. Roman, 1968

4. Between Senye and Izaguirre, Rio Muni, coll. Roman, 1968

 

Key Features:

Male body; irregular bars, mainly in the rear part. Yellow margin in D, C, A. Red submargin bars or dots in the inner part of C. D larger and higher than australe.

Karyotype: from n = 20, A = 31 to n = 10, A = 20.

Meristics: D = 10; A = 15; D/A = +6

Size: male, 60 mm, female, 55 mm.

 

Ecology: no personal experience, probably the same as australe.

 

Distribution: South Cameroon and Rio Muni. It is replaced by calliurum northerly and australe southerly.

 

Note: further study is strongly needed to determine the status of pascheni, to better define ahli and its karyotypical limits which are now too large.

 

1.1.4 Exceptional Fauna

 

Aphyosemion cameronense (Boulenger, 1903)  12  CAM

 

This species lives mostly in the inland plateau. It has been reported, on rare occasions, in plains, near the foothills of the plateau in Cameroon and Rio Muni. (See Scheel, 1974).

 

 

1.2 The Genus Epiplatys .Gill, 1862

 

The genus Epiplatys is well represented in the studied area since two groups are sympatric throughout, but it is always less abundant than the fishes belonging to Aphyosemion.

 

Sexfasciatus is the first described member of the genus which is characterized by: a pike-like form; a mobile, well visible maxillary; a short dorsal and a strong black chromatism.

 

The two Epiplatys groups have a very wide distribution in coastal West Africa and may be also in the Congo, Zaire basin.

1. The fasciated group is living in the coastal plain and in the inland plateau: it is best defined by the six or more large black bars on the body of these large fishes. It is rare and represented by sexfasciatus and berkenkampi.

2. The grahami group seems to live only in the coastal part but species from the plateau may be related; it is best defined by a black pattern like "chevrons", on the body of these small fishes which can, exceptionally, be large; it is common and very often sympatric with the other Epiplatys, Aphyosemion and Procatopodins.

Not only are the two groups sympatric, but the juveniles are found schooling together, in the middle sunny calm parts of the brook. Instead, the adults take shelter in the herbaceous banks: they are rare compared to the juveniles, probably because the golden spot that they show above the head is conspicuous to predators.

 

1.2.2 The fasciated Epiplatys

 

The fasciated Epiplatys - i.e. sexfasciatus and berkenkampi do not form an evolutionary line if Clausen's point of view is followed: he placed the two fishes in different subgenera, namely Epiplatys and Parepiplatys according to the frontal neuromast pattern. In fact, those two fishes are isomorphic, show a similar colour pattern and a similar karyotype. Neuman (1978) partly based his description of berkenkampi on the fact that berkenkampi resembles multifasciatus by having intermediate bars on the sides: there are indeed populations of sexfasciatus which show the intermediate barred pattern and on the other hand, mesogramma, the northern member of multifasciatus in the Central African Republic has none . Moreover the separations in Gabon, approximately at the level of Fougamou have to be discussed.

 

Fishes from Loc 30, 31 and 32 have been very difficult to name. Finally, the status of this species remains obscure, if valid.

 

The fasciated Epiplatys are often sympatric with the singa superspecies. They like warm stagnant waters but are also collected in the rapid brooks at the first steps of the inland plateau, e.g. Ndjolé and Kinguélé in the Crystal Mountains for sexfasciatus. In aquaria they are not easy to maintain, quarrelsome and non-annual: 2 weeks incubation time in water.

 

Epiplatys sexfasciatus (Gill, 1862)  13  SEX

 

Epiplatys sexfasciatus Gill: Proc. Acad. Nat. Sci. Philadelphia, page 136 footnote. Types from "Gabon".

Redsicribed by Boulenger (1915) from the Abanga River, northern Gabon.

 

Meaning of the Name: six-barred (Latin)

Main Synonyms: Haplochilus infrafasciatus Günther, 1866

Aplocheilus sexfasciatus Scheel, 1974

Three subspecies have been named, some seem very doubtful at least sexfasciatus baroi Berkenkamp, 1975.

 

List of Recent Localities:

1. 15 Km off Bata towards Machinda, northern Rio Muni, coll. Roman, 1966

2. Rio Ekuko, northern Rio Muni, coll. Roman, 1967

3. Between Senye and Rio Benito, central Rio Muni, coll. Roman, 1968

4. Subsidiary of the Aye, near Cabo San Juan, southern Rio Muni, coll. Roman, 1968

5. Bonobono, Cogomar, Rio Benito, southern Rio Muni, coll. Roman, 1968

6. Lower Benito, central Rio Muni (?), coll. Scheel, 1969

7. Libreville Airport, northern Gabon, coll. Herzog and Bochtler, 1973 (K)

8. Cap Estérias, northern Gabon, Loc 1-36, coll. Huber and Radda, 1976 (K)

9. 18 Km east of Ndjolé, Loc 6, northern Gabon, coll. Huber and Radda, 1976

10. (?) Near Mandilou, Loc 31, central Gabon, coll. Huber and Radda,"1976

11. (?) 43 Km north of Fougamou, Loc 32, central Gabon, coll. Huber and Radda, 1976

12. 9 Km south west of Bifoun, Loc 34, northern Gabon, coll. Huber and Radda, 1976

13. 6 Km south of Kouamé, Loc 57, northern Gabon, coll. Huber, 1976

14. 2 Km after the crossroad towards Kinguélé, Loc 58, northern Gabon, coll. Huber, 1976

15. Near Ndjolé, Loc 217, northern Gabon, coll. Huber, 1979

16. 40 Km north of Ntoum, near Cocobeach, Loc 231, northern Gabon, coll. Huber, 1979

17. 19 Km north of Ntoum, Loc 232, northern Gabon, coll. Huber, 1979

18. 29 Km east of Libreville, Loc 220, northern Gabon, coll. Huber, 1979 (K)

19. 10 Km east of Lambaréné, northern Gabon, coll. Pap, 1980 (K)

 

Key Features:

Male with a yellow phase: many red dots regularly in series, on the sides and D, upper C. Yellow V and A. Six vertical bars. Well delimited on a green (up) and blue (down) body.

Female with six bars on light brown body. Brown red dots.

Karyotype: n = 24; A = 25 (Loc 220)

Meristics: D = 11; A = 16-17 Size: male, 80 mm, female, 60 mm

 

Ecology: same as singa but prefers clear waters, sexfasciatus is rarer than singa in Gabon.

 

Distribution: very wide: from Togo to northern Gabon; in the studied area: Rio Muni, northern Gabon until approximately the latitude line of Fougamou. Southerly, it is replaced by berkenkampi.

 

Note: the close study of the fauna around the Fougamou, border line would be of great interest.

 

Ep. berkenkampi Neumann, 1978  14  BER

 

Epiplatys berkenkampi Neumann, Aquarien Terrarien 25 (4): 125 - 127.

Types from 30 Km South of Lambaréné, central western Gabon, coll. by Bochtler

 

Meaning of the Name: Dedicated to H.O. Berkenkamp

 

Main Synonyms: Ep. aff. multifasciatus Radda and Huber, 1977

Ep. aff. multifasciatus Huber, 1978

 

List of Recent Localities

I. 30 Km south of Lambaréné towards Bigouénia/Mora, Central Gabon, coll. Bochtler, 1976 (K)

2. Near Banyanga, Mayombé Hills, Southern Gabon, Loc 27, coll. Huber and Radda, 1976

3. Near Ngoudoufola, central Gabon, Loc 30, coll. Huber and Radda,1976

4. 10 Km east of Mayumba, southern Gabon, Loc 205, coll. Huber, 1979

5. 28 Km east of Mayumba, southern Gabon, Loc 206, coll. Huber, 1979

6. (?) 46 Km south-east of Lambaréné, towards Mouila, coll. Pap, 1980

 

Key Features:

Male with irregular barred pattern; six main bars and additional intermediate ones less visible. Fin basic color blue green, red dotted with blue black margin. Closed neuromast pattern, contrary to sexfasciatus, but seems related.

Karyotype: n = 24; A = 25 (Scheel, pers. com.)

Meristics: D = 9-10; A = 14-16; LL = 29-30+2 (my data from Loc 27)

Size: male, 80 mm, female, 60 mm

 

Ecology: same as sexfasciatus. Sympatric with singa all over the range. Prefers clear water biotopes and is rarer than singa.

 

Distribution: coastal plain in central and south Gabon, Congo and most probably Cabinda; replaces sexfasciatus approximately South of the latitude line of Fougamou.

 

Note: still a doubtful species (see above). It would be interesting to study closely the living phenotypes of Cabinda (see the specimens of Lundo, Mali River, coastal Cabinda, British Museum). If they are matched, a connection would be possible with the Congo Basin multifasciatus group (cf. Huber, 1980).

 

1.2.2. The singa superspecies

 

The singa superspecies is the most important Epiplatys in the studied area: it is variable in terms of colour pattern and morphology during growth. It is composed of two elements: grahami and, mainly singa whose separations may be situated in the Southern Part of Rio Muni without a biogeographically evident base. In Aquaria these fish are easy to maintain, quiet and non annual. Incubation time: 2 weeks in water.

 

Epiplatys macrostigma, ansorgii, and ornatus, are all junior synonyms of Ep.singa Boulenger.

 

The Epiplatys species collected south of the Rio Muni have faced many nomenclatorial changes during their history, mainly for three reasons.

1. macrostigma and ansorgii have been described in the same paper by Boulenger and it was rather surprising that Boulenger did not compare them. The type localities were approx. 1000 kilometres apart, respectively Cabinda and Masoma River, near the Crystal Mountains in northern Gabon. Moreover the types of ansorgii are large indeed (7 to 8 cm) I have reviewed them from the British Museum and they are identical by morphological data and colour pattern to macrostigma.

2. ornatus has been described by Ahl without type locality. It is not separable from ansorgii and macrostigma. For historical reasons, ornatus may come only from northern Gabon or southern Congo (Scheel, 1968); it is then a simple synonym of either.

3. singa has been described from Boma, lower Congo, Cabinda. But Boulenger (1915) identified fishes from Boma as macrostigma and reported singa from Stanleyville, central Congo Basin. This mislabelling is the source of many confusions; such as singa placed in Aphyosemion, a strain of "schoutedeni" being identified as singa in the fifties by aquarists.

The types I have reviewed clearly belong to Epiplatys and cannot be separated from the three above.

 

One separation has been proposed by Scheel (1974) based on the colour pattern of juveniles: northern sub-phenotype with bars in juveniles, southern sub-phenotype without. After having seen live specimens, young and adult, from the 13 listed locations and older Museum material, I confirm that variability is higher within a population than between northern and southern populations and do not hesitate to retain only one taxon as valid: Ep. singa.

 

Ep. singa Boulenger, 1899  15  SIN

 

Haplochilus singa Boulenger - Ann. Mus. Congo Zool. I: 113, pl. XLVII, fig. 1.

Types from Boma, Lower Congo, South Western Zaire, coll. Ansorge.

 

Meaning of Name: vernacular (according to Boulenger).

 

Main Synonyms: Haplochilus macrostigma Boulenger, 1911

Haplochilus ansorgii Boulenger, 1911 (frequent misspelling: "ansorgei", since Pellegrin, 1930)

Panchax ornatus Ahl, 1928

Aplocheilus singa Scheel, 1974

 

List of Recent Localities:

1. Libreville Airport, northern Gabon, coll. Bochtler and Herzog, 1972 (K)

2. Cap Estérias, northern Gabon Loc 3, coll. Huber and Radda, 1976 (K)

3. 17 Km east of Bifoun, northern Gabon Loc 5, coll. Huber and Radda, 1976 (K)

4. 59 Km North of Ndendé, southern Gabon, Loc 28, coll. Huber and Radda, 1976

5. Ngoudoufola, northern Gabon, Loc 30, coll. Huber and Radda, 1976

6. Mandilou, near Fougamou, northern Gabon, Loc 31, coll. Huber and Radda, 1976

7. Between Matida and Boma, lower Congo, southern Zaire, coll. Wood, 1977

8. 5 Km east of Bas Kouilou, southern Congo (RPC 1), coll. Buytaert and Wachters, 1978

9. 10 Km east of Pointe Noire, southern Congo (RPC 2), coll. Buytaert and Wachters, 1978

10. Near Mouila, southern Gabon, Loc 21, coll. Huber, 1979

11. Near Mayumba, southern Gabon, Loc 204, 205, coll. Huber, 1979 (K)

12. Near Mandji, northern Gabon, Loc 216, coll. Huber, 1979

13. Near Andem, east of Ntoum, northern Gabon, Loc 219, coll. Huber, 1979

14. Near Soumboukassesso, on the road Pointe Noire-Brazza, southern Congo, coll. Agnèse, 1980

15. Between Bas Kouilou and Mandingo Kayes, southern Congo, coll. Agnese, 1980

16. 10 Km East of Lambaréné, northern Gabon, coll. Pap, 1980.

 

Key Features:

Male body: pattern variable within a population, less than within the range: 6 -7 irregular series of red brown dots; the lower series follows the line of the body and is oblique. Black bars in "chevrons" only in juveniles (not always). All fins dotted.

Female: no or very few dots in fins.

Karyotype: unknown

Meristics: D = 8; A = 14; LL = 27-28

Size: male, 70 mm, female, 60 -65 mm; exceptionally 80-90 mm in nature

 

Ecology: very opportunistic; seems to stand dirty waters in contrast to sexfasciatus and berkenkampi

 

Distribution: very wide: from northern Gabon to Zaire and maybe further southward. Climbs exceptionally the first steps of the inland plateau, then disappears without being replaced by another Epiplatys species.

 

Ep. grahami (Boulenger, 1911)  16  GRA

 

Haplochilus grahami Boul. Ann. Mag. Nat. Hist. 8 (8).

Types from swamps near Lagos, southern Nigeria, collected by Graham.

 

Meaning of Name: dedicated to W.H. Graham

 

Main Synonyms: Epiplatys nigromarginatus Schultze, 1937 (?)

Aplocheilus grahami Scheel, 1974

 

List of Recent Localities:

1. 6 km south of Bata toward Rio Benito, northern Rio Muni, coll. Roman, 1968

2. 35 km off Bata, subsidiary of Ué river, northern Rio Muni, coll. Roman, 1968

3. Between Senye and Rio Benito, northern Rio Muni, coll. Roman, 1968

4. Subsidiary of Aye River, southern Rio Muni, coll. Roman, 1968

5. Between Ebam and Macora, coll. Roman, 1968

 

Key features:

Male body pattern: similar to singa but black crossbars in juveniles and adults. More colourful; yellow or green unpaired fins, metallic brilliance on body. Red dots in fins.

Female with no or few red dots in fins.

Karyotype: n = 24; A = 25

Meristics: D = 7-11; A = 15-17; LL = 26-30

Size: male, 60 mm, female, 45 mm

Ecology: marshy areas; juvenile specimens, in Nigeria, are reported to shoal with juveniles of sexfasciatus and closely resemble these (Scheel, 1974).

 

Distribution: in the studied area, restricted to northern and central Rio Muni; more southerly, it is replaced by singa. although no ecological barrier seems to exist. It may be that singa and A. striatum start at the same level.

 

2. THE PROCATOPODINS

 

2.1 Definitions and remarks on Clausen systematics

 

2.1.1 The value of the micro-morphological characters

 

Procatopodins are a large group of Cyprinodonts but they occupy the African continent only. Their abundance is inversely related to that of the Rivulins. In western coastal Africa, they are represented by only two groups whereas in the Congo Basin, Angola and eastern Africa numerous groups are present with a high variability. Procatopodins have either a deep body (Procatopus - like forms) or an elongated one (Micropanchax- like forms) with obvious intermediates; the height of the body depends on the stage of growth, strong allometries occur.

They exhibit small sizes (except two special lacustrine fishes), a compressed body, a weak sexual dichromatism (except Poropanchax subgen.). Fins are poorly coloured except for a blue sheen, and the eyes show blue yellow reflections (i.e., the "lampeyes").

Until recently the best definition of Procatopodin was the high set pectorals, the body pattern and morphology and the ecological niche: shoaling fishes in flowing streams.

 

Several genera had been described, most of them poorly, on the base of branchiostegal rays, teeth type, level of pelvic fins, predorsal area and caudal peduncle (Myers, 1938).

 

In 1967, Clausen (op cit) described several micro-morphological characters for Rivulins and Procatopodins. Unfortunately his work was, from his own words - "not mature enough" - to establish a stable systematic but he tried to assemble some groups of genera.

1. Ctenoidy, and

2. Frontal neuromast pattern, especially for taxonomy.

 

During 1979 - 80, Procatopodins have been my primary study and, though the results are still preliminary, I feel it necessary to publish some of them as they modify what has been our understanding since Clausen: As it was the case for the Rivulins (Huber 1978), ctenoidy and neuromast systems appear to have no or little taxonomic value, but a descriptive interest for the Procatopodins.

 

1. Ctenoidy appears to have no statistical value. It is a characteristic of old age if it is exhibited.

Two contradictory examples: first, there are exceptionally ctenoid spinules on the sides of old Procatopus males from Southern Cameroon while ctenoid scales are frequently present in the Congolese and Gabonese Procatopus (Clausen's Plataplochilus) but not all the time and many adult individuals lack them, especially in the "dwarf" populations (see Stauch's cabindae collection).

More generally ctenoid scales are reported or not from different species which seem related by morphological and geographical standpoints: nimbaensis (by Clausen, not by me), schioetzi (by me) lamberti (some only, by me).

Within a single species the occurrence or not of ctenoidy is reported (e.g. in silvestris (syn. of stictopleuron in Tervuren collections). Depending on the population and, according to Clausen, in Micropanchax, "it is distinctive at the species level", only. Finally and it seems the most important, scale ctenoidy is indeed a common character buts its degree of development varies greatly from the small minute "buttons" as in moeruensis to the strong hairy structure as in Lamprichthys or the new species terveri, with all the possible intermediates.

 

2. The frontal neuromast pattern appears even more a descriptive character.

Basically, the same number of sensitive sites are observed in Procatopodins, only the pattern of superior skin is different: 1 primary anterior pair, 3 middle pairs, 3 posterior pairs behind the eye, 1 posterior pair far behind. Three extreme schemes can happen, in my own observations:

a) the middle neuromasts are hidden at bottom of pores or openly exhibited,

b) the middle neuromasts are situated in longitudinal grooves or isolated (especially the anterior pair from the 2 other neighbouring ones),

c) the primary pair (after the last one) is exposed as in Aphyosemion or Epiplatys or reduced to a small hardly visible "button".

If these 3 variables are combined and the possibility of intermediates assumed, then there is a multitude of neuromast patterns. This is what happens; with variability within a species and within a superspecies.

A good example might be camerunensis Radda. The neuromast pattern of the middle pairs is fully exposed but not well visible and the first pair is isolated; the pattern of the anterior pair and the last one is nearly invisible (small buttons) whereas the 3 posterior ones are normal. The overall neuromast pattern is unique and surely would deserve a special place following Clausen. However if one studies the "isomorphic" species of the Inland Plateau of Tchad, Gabon, Congo and Zaire, the pattern of camerunensis appears to be just an element of a continuous variation; the northern normani shows a fine tubular system (as in Poropanchax) and the southern stictopleuron from the Ivindo to the Zaire basin shows fully exposed systems, even the last posterior pair.

Therefore, I prefer to consider micro-morphological characters as descriptive rather than taxonomic.

 

2.1.2 Proposal for a new Procatopodin systematic.

 

The Procatopodin systematics should be based on biogeography, karyotypes, egg membrane, colour patterns and general morphology, in the future, in order to form evolutional groups or superspecies.

Regarding morphology, such "old" characters as the compressed, or not, type of body, the level of pectorals, caudal peduncle breadth, and D/A rays counts and position may be useful but one should be careful of the height of body because of a possible allometry during growth. Micro-morphological structures might be useful to separate species, a posteriori.

 

2.1.3 Preliminary grouping of Procatopodin species.

 

Though our knowledge is still fragmentary, there are some immediate facts that can be forwarded:

 

Some elements can be separated from the bulk group of "mean" species.

They are studied thereafter.

- Cynopanchax Ahl, 1928 (type: bukobanus, Ahl 1928) is a simple synonym of Lacustricola Myers, 1924 (type: pumilus Boulenger 1906, a senior synonym of the former, according to Wildekamp, 1977)

- the status of Congopanchax, Hylopanchax, the normani group (??), and Lacustricola is not clear to me, but, if valid, they should not deserve more than subgeneric status.

- Platypanchax Ahl, 1928 is a very doubtful genus: nomen nudum or simple synonym as its type species modestus has an obscure status: Hypsopanchax? Micropanchax?

 

Aplocheilichthys, a monotypic genus.

 

The first attempt to delineate the Procatopodin line is to separate one species, spilauchen, which is the type for Aplocheilichthys.

Its biology is unique in western Africa and can be compared to the eastern Pantanodon, but its morphology is different. It is the most widespread monotypic line in Africa from Senegal to Zaire and this distribution has been achieved though the brackish water adaptation.

Besides, spilauchen combines low set pectorals, a deep caudal peduncle, a deep body, little compressed form, and an original fasciated colour pattern. Therefore it is separated from the major group of Procatopodins that was named Aplocheilichthys in the past and Micropanchax here. It is less separated from Procatopus by general morphology but the head and the insertion of pectorals are completely different.

In summary, Aplocheilichthys Bleeker 1863 is now defined by a single species, inhabiting the West African brackish lagoons or mangroves and rarely found in soft water. It has a massive appearance, a marked sexual dichromatism, rounded fins, low set pectoral, long Ventrals and shows an alternate of narrow brilliant yellow and brown vertical bars. Its neuromast cephalic pattern is complete and open; scale ctenoidy may be observed.

 

Micropanchax, the basic genus for non Procatopus like species.

 

The remaining bulk of species, having a non Procatopus like morphology is assigned to a heterogeneous genus, i.e. Micropanchax Myers, 1924, because it is the senior taxon (Lacustricola Myers, 1924 was described one page after) and because its type species schoelleri (= loati Boulenger) is a fairly average one.

Micropanchax is composed of several superspecies, some of them being perhaps separated in the future:

- the eastern group (Micropanchax typical), savannah dwelling, the rift valley lakes group being included or not.

- the western group which is better known to the author.

 

The western groups belonging to Micropanchax

In Western Africa, 4 groups can be disclosed which contain phylogenetically related species:

- The Poropanchax group of slender coastal species from Ivory Coast to Rio Muni (see the review).

- The corresponding slender species of the inland plateau from (Guinea?) Liberia to Zaire: normani;, camerunensis, stictopleuron, that might deserve the Hylopanchax name (subgenus).

- The deep bodied western group of the inland plateau from Guinea to Benin: kabae, lamberti, monicae, nimbaensis (see drawing of head), schioetzi, yet without an actual name.

- The deep bodied southern group of the plateau and the Congo Basin, named at the genus level Hypsopanchax, with platysternus, deprimozi, jubbi, jobaerti and zebra. The genus status may be valid but deserves better studies, specially compared to Procatopus.

There remains three species I have not seen and cannot place, pfaffi, baudoni, hutereaui and also the Angolan species that seems probably related to the Eastern forms by the means of the Shaba Province in Southeastern Zaire.

 

2.1.4 Lamprichthys Regan, 1911 and Laciris new genus, two relict pelagic monotypic genera.

 

During my studies in Tervuren, I have checked Clausen's excellent observations for Lamprichthys tanganicanus a true but isolated Procatopodin (Mohanga Boulenger, 1911, is a junior synonym of Lamprichthys since Myers, 1924) and was very surprised to discover another relict species that deserves a separate genus status too: pelagicus (Worthington, 1932) from Lake Edward (5 specimens No. 142820-814).

Curiously these two fishes show common characters:

- They are purely lacustrine species, living in the deep waters, endemic to two rift valley lakes: Tanganyika and Edward.

- They are large, at least twice the size of the common Procatopodin.

But they are very different and I do not hesitate to propose a separate naming for the monotypic pelagicus:

 

Laciris nov. gen.

Diagnosis: a large rather elongate species that has a very low insertion of Pectorals and show a very vestigial neuromast cephalic pattern: only two curved narrow grooves are exhibited without pores or sensory "buttons". The preserved fishes present only the fine black line on the sides and a broad black vertical margin in the caudal.

 

2.1.5 Key elements to be disclosed.

 

Our knowledge of Procatopodin is still in its infancy.

1. At the species level, it is necessary to obtain living material and prepare re-descriptions according to colour pattern, karyotypes and crossings. We must admit that today the separation of species is based on morphologic proportions and meristics. But these data are not very informative (and even value-less in the case of Procatopus) because of the variability of these species and because of the allometry in growth.

2. At the group level, it is necessary to study in detail their allopatric and sympatric occurrence and to prepare precise distributions. The Procatopodins are not so different from the Rivulins: except in the basic choice of biological niche and behaviour, and their much wider distributions, they should display a parallel system of evolution. The existence of intermediate fishes such as Adamas and perhaps Diapteron would favour this idea.

 

The major objective is then to obtain living material.

 

2.2 The Genus Aplocheilichthys Bleeker, 1867

 

The genus Aplocheilichthys is represented by its only species in the whole studied area: it is restricted to a narrow band parallel to the coast.

It is very abundant in the brackish water biotopes and more and more rare, gradually as one penetrates the country in soft water. Exceptionally, it can swim far up the river course if the influence of the tide is felt.

 

In Aquaria, spilauchen is an easy fish, provided it is maintained in large tanks with moving brackish waters. It breeds among the schooling group but may eat youngsters if the density is high: non-annual with 2 weeks incubation time in water, slow growth.

 

Aplocheilichthys tschiloangensis Ahl, 1928 is a junior synonym of spilauchen.

 

The origin of the types of tschiloangensis is Landana, near the estuary of the Tschiloango, Cabinda. By morphology this taxon is not separated from spilauchen; by biotope, neither (Ahl states a mangrove), by colour pattern neither; by distribution, neither (spilauchen has been reported until the Zaire River); a final check of the preserved specimens confirms the identity of the two names.

 

Aplocheilichthys spilauchen (Duméril, 1859)  17  SPI

 

Poecilia spilauchena Duméril: Arch. Mus. 10 : 258 fig 5.

Types from the lower Senegal, western Africa.

 

Meaning of the Name: spotted neck (Greek)

 

Main synonyms: Aplocheilichthys typus Bleeker, 1863

Haplochilus spilauchen Boulenger, 1915

Aplocheilichthys tschiloangensis Ahl, 1928

Epiplatys sp. Daget, 1950

Aplocheilichthys spilauchena Roman, 1971 (frequent misspelling)

 

List of Recent Localities

1. Rio Utonde, 12 Km from the landing stage, Rio Muni, coll. Roman, 1966

2. Between Senye and Rio Benito, southern Rio Muni, coll. Roman, 1968

3. Cap Estérias, northern Gabon, coll. Arnoult, 1973 .

4. Mayumba, 28 Km towards Tchibango, Loc 206, southern Gabon, coll. Huber, 1979

5. Between Cocobeach and Milembié, Loc 231, northern Gabon, coll. Huber, 1979

 

Key Features

Male, heavily bodied but less flattened than Procatopus. Fully developed open neuromast system, indistinct light black-brown bars on a metallic yellow body and fins. White thin margin in D, C, A (not always): Upper insertion of Pectorals.

Karyotype: n = 24; A = 47

Meristics: D = 6-8; A = 11-14; LL = 26-28

Size: male, 60 mm, female, 55 mm (large)

 

Ecology: opportunistic; prefers mangrove and swampy brackish waters where it is sympatric with Periophthalmus sp. Also in soft water brooks together with Aphyosemion, Epiplatys and other Procatopodins.

Likes a brighter light and higher temperature than other Procatopodins. Good swimmer. Not always schooling.

 

Distribution: the largest in Africa: from the Senegal River to the Zaire River - not recorded by Poll in Angola. Restricted to the littoral band, narrower than 20 Km. In that sense may be matched with A.australe, which however is not found in brackish water.

 

2.3 The genus Micropanchax Subgenus Poropanchax

 

The subgenus Poropanchax, Clausen, 1967, is the best defined of the Procatopodin by phylogenetic standards: it should be composed of the macrophthalmus group, i.e. macrophthalmus Meinken 1932 (eastern Benin, southwestern Nigeria, northwestern Cameroon) rancureli Daget, 1964 (southern Ivory Coast), hannerzi, Scheel 1967 (Biafra), scheeli, Roman 1971 (southwestern Cameroon, Rio Muni) and probably unnamed phenotypes from west of Ivory Coast.

In my opinion, normani Ahl belongs rather to the Inland Plateau group.

 

Poropanchax is characterized by a group of exclusively coastal forest fishes, shoaling in soft or brackish waters. Morphology: elongate body, no preorbital scale, no branchiostegal appendage, posterior position of Pectoral fins. Cephalic medium neuromasts pattern: three independent pores; strong sexual dimorphism.

Poropanchax is poorly represented in the studied area: scheeli inhabits the northern coastal part of Rio Muni.

 

Micropanchax (Poropanchax) scheeli (Roman, 1971)  18  SCE

 

Aplocheilichthys macrophthalmus scheeli Roman: Fundacion La Salle de Ciencias Naturales, Barcelona: 178-181, fig. 79.

Types from Rio Utonde, northern Rio Muni, raised to the species status by Scheel in Daget 1979.

 

Meaning of the Name: dedicated to J.J. Scheel.

 

I have seen one syntype of ngaensis in the Paris Museum and compared to my collections of the same area, of around Ntoum (mimus) and of around Lambaréné (chalcopyrus). Their colour pattern is similar, only minor differences are observed (extension of shining zone, unpaired fins) that are at the population level. No difference in maximal size is observed. Lambert had separated two forms on the basis of more or less elongated body and the level of insertion of the dorsal (60%-64% of standard length for mimus and 66%-71% for chalcopyrus). Reports of ngaensis in southern Gabon are highly probable in the future.

 

Pulcher is a junior synonym of miltotaenia.

 

Pulcher is just another case, even simpler: those two fishes show the same characteristic red median band and the two type localities are separated by 100 kilometres approximately. Another feature is the upper filament in the caudal of pulcher in old males. I have not collected miltotaenia, south of Lambaréné, but in some populations of ngaensis the filament was present, not in others.

 

Loemensis and micrurus (?) are junior synonyms of cabindae which may be a good species.

 

The status of the Congo species is more difficult to evaluate. I have studied preserved material only. The colour pattern of cabindae has been reviewed by Lambert (1967), and if this is verified, it seems sufficiently distinct from the other two species: however, it is hardly understandable that another species - cabindae - may appear south of miltotaenia without any geographical barrier.

Loemensis from Southern Congo is a clear synonym of cabindae: the two descriptions are similar except for the fin data, but the variability of Stauch's collections fuses the two descriptions. I have checked loemensis types.

Micrurus may be a synonym of cabindae: the two type localities are closed:

- in the Koulilou estuary, only two Procatopodins are present: cabindae and Aply. spilauchen. It seems hardly possible that micrurus be spilauchen because tschiloangensis (=spilauchen) is described in the same paper and from the same area and because the micrurus drawing shows a Procatopus-like form

- the two morphologies are similar D = 6; A = 12

- micrurus presents a median band on the sides.

However a final check on the types in Berlin is desirable, if they are not lost.

 

2.4.3 The Procatopus species from Savannah Inland Plateau

 

Description of Proc. terveri  n.sp.

 

The thorough study of the Procatopus material collected by Baudon, Stauch, Lambert and Huber and Radda has inclined to reconsider the identification of the Procatopus from Southeastern Gabon, in the savannah or gallery forest Inland Plateau.

Its case is not unique, as in the Zanaga forest area is living Hypsopanchax zebra which is very isolated from its relatives from the eastern Zaire basin: Hypso. platysternus, deprimozi, jubbi, jobaerti.

 

It appears then that this specific area might have played an important role in the phylogeny of Cyprinodonts, 2 relict Procatopodins, more than 12 different Aphyosemion species.

 

Procatopus terveri is dedicated to my good friend Dr Denis Terver, Director of Nancy Museum and Aquarium, France, who has helped and heavily supported me for all these years including during the preparation of my thesis.

 

Procatopus terveri n. sp.

 

Holotype: (MNHN 1930-50), 33.3 mm standard length; 42.5 mm total length. From the Mpassa River (Paris Museum No 162-2-29-2), Upper Ogooué drainage, south eastern Gabon. Identified by Pellegrin as Haplochilus loemensis M. Baudon leg.

Paratypes: (MNHN 1930-51) 8 specimens from the Leyou River, southwest of Moanda, upper Ogooué drainage (Paris No. 11-2-29-2) M. Baudon leg.

Paratypes: (RGMRAC: 20203-204), 2 specimens from the same locality as Holotype (Tervuren Museum in Lambert 1967 "Plataplochilus cabindae").

Paratypes: 5 specimens from 7 km from Franceville towards Onkona, southeastern Gabon, coll. Lambert, 26th October 1964.

Additional Material: 13 Km NW of Moanda towards Mounana, south eastern Gabon (loc 15 - type locality of A. coeleste) coll. J.H. Huber and A.C. Radda.

 

Morphology: Large Procatopus with high D and A data. Strong Ctenoidy on sides, front, fins and face. Three rows of small scales are reported below the eye - Irregular scalation on head - Neuromast cephalic pattern with 8 pairs of pores sometimes communicating below. Two sensory organs are visible on the far rear part of the head as in M. stictopleuron (syn. silvestris, Huber in preparation), 1 pore out of 3 scales on lateral line. Other characters enter within the diagnosis of the group. (See table I for data of the types)

 

Colour Pattern: After preservation, uniform light brown with the common fine black median line. Living: see the identification key.

 

Conclusion: Proc. terveri n. sp. is best defined by its isolated origin, its colour pattern, its massive morphology, its large number of rays, and maybe the three rows of scales on the face.

 

Procatopus ngaensis (Ahl, 1924)  19  NGA

1. 19 km south of Lambaréné towards Mouila, central Gabon, coll. Lambert 1962

2. 8, 18,29,30 Km south of Lambaréné towards Mouila, central Gabon, coll. Lambert 1962

3. 40 Km east of Libreville towards Kango, northern Gabon, coll. Lambert 1964

4. 20 Km south of Lambaréné, central Gabon, coll. Bochtler and Herzog 1972

5. Surroundings of Lambaréné, northern Gabon, coll. Herzog 1973 (K)

6. 10 Km east of Lambaréné, northern Gabon, coll. Pap 1980

 

 

Ecology: see Proc. ngaensis

 

Distribution: known only from Northern and Central Gabon, probably also in Rio Muni.

 

Procatopus cabindae (Boulenger, 1911)  21  CAB

 

Haplochilus cabindae Boulenger, Ann. Mag. Nat. Hist. 8 (8): 264-265.

Types from Cabinda "Portuguese Congo", coll. Ansorge.

 

Meaning of the Name: from the type locality name.

 

Main Synonyms: Plataplochilus cabindae Lambert, 1967

Haplochilus loemensis Pellegrin, 1924

Aplocheilichthys micrurus Ahl, 1928

 

List of Recent Localities:

1. 85 Km north east of Pointe Noire towards Sounda, southern Congo, coll. Lambert, 1962

2. 45 Km east of Point Noire towards Loubomo, southern Congo, coll. Lambert, 1962

3. Djembo, southern Congo, coll. Stauch, 1962

4. Zibati subsidiary of the Kouilou, southern Congo, coll. Stauch, 1963

5. Yangala, Youbi, southern Congo, coll. Stauch, 1963

6. Tchitobo near Sintu southern Congo, coll. Stauch, 1963

7. Tombo road towards Sounda, southern Congo, coll. Stauch, 1963

8. Subsidiary of the Loémé, Mayombé Hills, southern Congo, coll. Stauch, 1963

9. Subsidiary of the Likouéné road towards Sounda, coll. Stauch, 1964

10. 20 Km North of Lébamba (Ioc 23) southern Gabon, coll. Huber and Radda, 1976

11. 5 Km east of Ndendé southern Gabon, coll. Huber and Radda, 1976

12. Near Banyanga (Loc 27) southern Gabon, coll. Huber and Radda, 1976

13. Between Loubomo and Loudima (RPC 3) southern Congo, coll. Buytaert and Wachters, 1978

14. (?) 12 Kms east of Tchibanga (Loc 203) southern Gabon, coll. Huber, 1979

 

Key Features:

Male with a broad orange brown band on sides. Orange band in inner part of D, A Yellow V. Orange margin up and down in C.

Karyotype: Unknown

Meristics: D = 9-10; A = 15-17; LL = 30-32

Size: male, 50 mm; female, 45 mm

 

Approximately 200 specimens seen from the Stauch's collection (MNHN, Paris). The living colour pattern of the male from the type area is not known to me, thus the specimens from southern Gabon are tentatively placed here.

 

Ecology: same as other Procatopodins, sympatric with the southern Rivulins: A. primigenium, microphtalmum, australe, Ep.singa, berkenkampi.

 

Distribution: Mayombé Hills in southern Gabon, Congo and Cabinda, north of the Zaire River.

No barrier seems to exist between the ranges of miltotaenia, ngaensis and cabindae and further studies are needed to determine its validity.

 

KEY TO THE SOUTHERN PROCATOPUS SPECIES

1. No median band on side, except the fine black line.

1.1 Blue with two green copper shining zone posterior to D/A - Coastal plain. Pale yellow D/A with fine orange margin.

ngaensisAhl. D = 9-10; A = 16-17

(syn. = mimus. D = 10-12; A = 15-16)

(syn. = chalcopyrus D = 6-10; A = 14-18)

Upper filaments in C of some males.

1.2 orange to yellow body, little blue shining. Yellow to orange blotches in D/A. Inland plateau.

terveri Huber D = 11-12;A = 18-19

2. Broad median band on side

2.1 Fine golden line above the red median band. D, A, V pale yellow with a fine orange margin.

Coastal plain

miltotaenia Lambert D = 12-15; A = 14-17

(syn. pulcher D = 10-12; A = 14-15, upper filament in C of some old males)

2.2 Olive brown median band, fins yellow greyish - Inner part of D and A, orange band. Coastal plain

cabindae Boulenger D = 9-15; A = 15

(syn. loemensis D = 11-12; A = 14)

 

MORPHOMETRIC AND MERISTIC DATA OF TYPES OF PROC. TERVERI  n. sp.

TABLE I

S.L.(mm) T.L. P.D.% P.A.% P.V.% Head% Height% D A L.L.
Holotype 30.50 33.0 129 61 55 43 26 31 12? 18? 27+3
30.51-1 34.4 132 61 58 42 26 33 11? 19 28
30.50-2 34.1 132 62 56 39 26 35 12? 18 28?+4
30.50-3 29.2 127 62 58 39 28 29 11 18 27?+2

 

 

D. CONCLUSION

 

This paper is intended to review our knowledge of the Southern Coastal Cyprinodonts from the Rio Benito to the Zaire River, and to propose clear systematics.

However the task is far from finished: most species need a better definition and new collecting places. Above all, the understanding of species separation without the occurrence of a known barrier is critical: e.g. separation of gabunense - exigoideum - primigenium in Aphyosemion, sexfasciatus and berkenkampi in Epiplatys, miltotaenia and cabindae in Procatopus.

Field studies in the bordering regions concerned are of primary interest for the knowledge of the Cyprinodonts evolution.

 

Paris, October, 1980

Line drawings by R.H. Wildekamp

 

BIBLIOGRAPHY

Ahl, E. 1928. Beiträge zur Systematik der Afrikanischen Zahnkarpfen. Zool. Anz. 79: 113-123.

Bochtler, F. and P. Heinrich, 1977. Gabunische Aphyosemion. DKG Journal 9 (5): 65-82.

Clausen, H.S. 1967. Tropical Old World Cyprinodonts. Akademish Forlag Kobenhavn: 1-64.

Huber, J.H. 1978. Caractères Taxonomiques et Tentative de Groupement des espèces du genre Aphyosemion. Rev. fr. Aquariol. 5 (I): 1-32.

Huber, J.H. 1980. Rapport sur la deuxième expédition au Gabon (Août 79): étude des Cyprinodontidés recoltes. Rev. fr. Aquariol. 7(2): 37-42.

Lambert, J. 1976. The Aphyosemion striatum complex: A Case Report. JAKA-KN 9 (4): 97-109.

Lambert, J. and H.S. Clausen, 1967. The genus Plataplochilus redefined. Rev. Zool. Bot. Afr. 76: 3-4.

Neumann, W. 1978. Ein neuer Epiplatys aus Gabon, Epiplatys berkenkampi spec. nov. Aquarien Terrarien 25 (4): 125-127.

Myers, G.S. 1938. Aplocheilichthys and its relatives in Africa (XIV). Copeia (3): 136-143.

Radda, A.C. 1975. The subgenus Chromaphyosemion. BKA Separatum.

Radda, A.C. and J.H. Huber, 1977. Cyprinodontiden Studien in Gabon V: Das Tiefland West Gabuns und die Mayombé Berge. Aquaria 24: 137-150.

Roman, B. 1971. Peces de Rio Muni, Guinea Equatorial. Fundacion La Salle de Ciencias Naturales, Barcelona: 236pp.

Scheel, J.J. 1968. Rivulins of the Old World. TFH Publications: 480pp.

Scheel, J.J. 1974. Rivuline studies. Ann. Mus. Royal Afrique Centrale, Tervuren, ser IN- 8-Sc.Zool. 211: 150 pp.

Wildekamp, R.H. 1977. Beschreibung von zwei neuen Leuchtaugenfischen aus Tanzania. Der Aquarien Freund (6): 130-116, fig. 1-18.

 

First published as a BKA Separatum and still sold by the BKA: this is the reason why this Internet version lacks all illustrations, figures and maps that are so important to the understanding.

English print reviewed and corrected by the author (2002).


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