Chapter 11
The Freshwater Fishes of Angola
Paul H. Skelton
Abstract The discovery and exploration of Angolan freshwater fishes was largely
effected by foreign scientists on expeditions organised by European and North
American parties. Current knowledge of Angolan freshwater fishes is briefly
described according to the main drainage systems that include Cabinda, Lower
Congo, Angolan Coastal region including the Cuanza, the southern Congo tributaries, the Zambezi, Okavango, Cunene and Cuvelai drainages. A biogeographic model
to explain the freshwater fish fauna of Angola is presented. The need for the conservation of Angolan freshwater fishes will rise with rapidly increasing pressures on
aquatic ecosystems from urbanisation, dams for power, agriculture and human
needs, habitat destruction from mining and deforestation, pollution, the introduction
of alien species and overfishing.
Keywords Africa · Cuanza · Cunene · Cuvelai · Okavango · Southern Congo ·
Zambezi
Historical Review
Despite Poll’s work (1967) over a very limited area, Angola remains a poorly known region
in which there remains much to be discovered (Lévêque and Paugy 2017a: 93)
The quotation above sums up the current state of knowledge for the freshwater
fishes of Angola. Poll (1967) is a landmark publication that reviews the historical
literature and records the known species and their distribution within the major river
basins of the country at that time. No other account of Angolan fishes as a whole has
been published. The current situation of a poorly known region is due to a number
of factors including the historical neglect of scientific exploration by the colonial
P. H. Skelton (*)
South African Institute for Aquatic Biodiversity (SAIAB), Grahamstown, South Africa
Wild Bird Trust, National Geographic Okavango Wilderness Project, Hogsback, South Africa
e-mail: P.skelton@saiab.ac.za
© The Author(s) 2019
B. J. Huntley et al. (eds.), Biodiversity of Angola,
https://doi.org/10.1007/978-3-030-03083-4_11
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P. H. Skelton
authorities, widely dispersed collections in international institutions from various
expeditions, the relative inaccessibility to scientists and collectors of the inland rivers and biologically rich areas, and the difficulties of aquatic exploration relative to
terrestrial fauna. The fact that there is no national Angolan depository for wet collections such as fishes fostered by local expertise is a further hindrance to discovery.
This aspect is fundamental to effective and sustained scientific productivity in any
endeavor such as ichthyology (Skelton and Swartz 2011). This accentuates the situation for Angolan freshwater fishes when it is recognised that Poll’s (1967) account
rested largely on the collection in the Diamond Company of Angola (DIAMANG)
museum in Dundo, which to a large extent is a product of the industrial diamond
mining activity in the mainly local drainages.
There are four distinct phases of scientific discovery of Angolan freshwater
fishes, Phase 1 – early explorations in the second half of the nineteenth century;
Phase 2 – scientific expeditions in the twentieth century until World War II; Phase
3 – post WWII to Angolan independence in 1975; and, Phase 4 – post independence
investigations.
Although several of Castelnau’s (1861) Lake Ngami fishes occur in the Angolan
reaches of the Okavango River system, the discovery and scientific description of
Angolan freshwater fishes was initiated by Steindachner (1866) describing a collection derived from the Atlantic coastal rivers. Steindachner’s species include some
iconic species such as his Kneria angolensis, Clarias angolensis and Enteromius
kessleri that help define the Angolan Atlantic coastal fauna. Guimarães (1884)
working with specimens in the Lisbon Museum (subsequently lost in the fire of
1978) (Saldanha 1978) submitted by the Portuguese explorer José Alberto de
Oliveira Anchieta provided detailed descriptions and illustrations of three species
taken from the Cunene and the Curoca Rivers from 1873–1884, viz. Schilbe steindachneri, Mormyrus anchietae and Enteromius mattozi.
The second phase of discovery (early twentieth century) is marked by a series of
expedition reports that include freshwater fishes. Boulenger’s (1909–1916) catalogue of fishes in the British Museum (Natural History) provided the basis of
Angolan freshwater fish fauna. Again the fauna included collections such as
Woosnam’s Okavango collection described by Boulenger (1911) that includes species which occur in Angolan reaches. Boulenger (1910) described a collection by
Ansorge from the Cuanza and Bengo Rivers that set the scene for considering the
uniqueness of the fauna of these rivers of the Atlantic coast. Other notable expeditions that included descriptions of freshwater fishes are the Vernay Angola
Expedition of 1925 (Nichols and Boulton 1927), the Gray African Expedition of
1929 (Fowler 1930), the Vernay-Lang Kalahari Expedition of 1930 (Fowler 1935),
the Swiss Scientific Mission to Angola 1928–1929 and 1932–1933 (Pellegrin 1936),
and Karl Jordan’s Expedition to South West Africa and Angola of 1933–1934
(Trewavas 1936). All these expeditions realised new species but were somewhat
limited in geographical scope to the southern Atlantic coastal rivers and to the
upland western reaches of the Cubango (Okavango) tributaries, the Oshana-Etosha
system and the plateau reaches of the Cuanza. This restriction emanates from the
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209
access realised by the Benguella Railway constructed from 1903 to 1928 from
Lobito port to Huambo and beyond (Ball 2015).
The third phase of scientific exploration of the freshwater fishes of Angola after
the WWII up until independence in 1975 is significant in that studies into ecological
aspects as well as the beginnings of a synthesis of the Angolan fauna occurred.
Ladiges and Voelker (1961) studied the fish fauna of the Longa River in the Angolan
watershed highlands. In addition to providing an ecological description and zonation of the river they described a few new species – Kneria maydelli from the
Cunene, Enteromius (as Barbus) roussellei and Chiloglanis sardinhai. Ladiges
(1964) followed up this article with an account of the zoogeography and ecology of
Angolan freshwater fishes based on a present/absent list of fishes in the Angolan
Coastal region, the Cunene, the Okavango Basin, and the Zambezi. Trewavas (1973)
recorded the cichlids of the Cuanza and Bengo Rivers that exposed the independent
derivation of the cichlid fauna of the Cuanza River in terms of the inland and coastal
reaches. An unpublished collection by Graham Bell-Cross from the Okavango and
the Cunene basins was deposited in the NHM in 1965, and this together with collections made by Mike Penrith from the State Museum in Windhoek, Namibia, provided specimens essential for Greenwood’s (1984) revision of serranochromine
species. Mike Penrith’s collections from the Cunene and Okavango in the early
1970s led to a few descriptions of new species by Penrith (1970) and Penrith (1973).
A major milestone account of Angolan freshwater fishes was Max Poll’s (1967)
Contribution à la Faune Ichthyologique de l’Angola – based largely on the extensive collections made by Barros Machado and others and lavishly illustrated with
excellent fish drawings as well as a gallery of photographs drawn from the Dundo
Museum in Lunda-Norte. Poll (1967) summarised the history of freshwater ichthyology and provided a full checklist of 264 species in 18 families and 54 genera as
then recorded from the inland waters of the country (excluding the Cabinda enclave).
A faunistic and zoogeographical account considered five ichthyological regions
(see below). Acknowledging a clearly incomplete inventory Poll listed the diversity
of his regions as follows: The Congo tributaries with 121 species are richest and
most diverse with characteristic families and genera known from the Congo Basin.
Next in diversity was the western Atlantic coastal region with 109 species, followed
by the Zambezi (62 species) but Poll pointed out that Bell-Cross had then recently
recorded 77 species from the upper Zambezi, also of tropical diversity but distinct
in character from the Congolean rivers. The Okavango-Cubango (57 species)
reflected its close connections to the Zambezi as well as to the Cunene (55 species)
in the west. The Cunene presented a mixed fauna of both the Zambezian elements
as well as Atlantic coastal nature.
Poll (1967) pointed out and summarised a few notable ichthyological characteristics of the Angolan fauna – there was no pronounced endemic character to the
fauna as a whole. The occurrence of lungfish (Protopterus) in Angola is known
only from records in Congo tributaries and from Cabinda, but Poll mentions that he
was shown a photograph by Ladiges of Protopterus annectens brieni from the
Cubango region (see this recorded in Ladiges 1964: 265). Such occurrence of lungfish in the Cubango or Okavango system has not yet been confirmed in spite of
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P. H. Skelton
extensive collecting in that drainage. Polypterids are restricted to Congo tributaries
as are freshwater clupeids (however marine or estuarine species also occur in
coastal Atlantic rivers). The presence of kneriids is a distinct feature of the fauna
especially of the escarpment reaches of rivers of the coastal region. Mormyrid
diversity (36 species) is relatively high, most especially in the southern Congo rivers. Characins (17 species) are less diverse but there is an equivalent representation
of Citharinids (16 species). The largest family represented in the country is the
Cyprinidae (79 species) and this is especially notable for the Atlantic coastal drainages (43 species) that is even richer than the Congo tributaries (27 species).
However the chedrins (Raiamas and Opsaridium and Engraulicypris) are poorly
represented – two species in Congo tributaries, one in the Zambezian region and
one in the Atlantic coastal drainages. Of the catfishes, the claroteids (10 species)
are a presence as are the clariids (17 species) of which the majority (11 species) are
represented across different provinces. Other catfish families present include schilbeids (eight species) mochokids (15 species), amphiliids (six species) and one
malapterurid. Cyprinodonts are relatively few (eight species) but show a particular
relationship across the Cassai-Zambezi watershed. Cichlids (31 species) are well
represented but not as well as the cyprinids. They are however more endemic in
nature, in particular the Atlantic coastal fauna (19 species with eight endemic). The
anabantids (three species) and mastacembelids (three species) are poorly
represented.
The last phase of ichthyological exploration informing on the fishes of Angola,
since independence in 1975, includes several taxonomic or systematic articles (e.g.
Greenwood 1984, Musilová et al. 2013); published river faunal accounts (Skelton
et al. 1985; Hay et al. 1997) and several unrestricted informal fish survey reports
emanating from specific projects (Bills et al. 2012, 2013; Skelton et al. 2016). These
surveys have exposed several new species to the fauna and together with phylogenetic studies on a wide range of lineages that include Angolan representatives, have
led to a vastly improved understanding of the distributional nuances that give explanation to improved biogeographical insights.
Freshwater Drainages and Ecoregions of Angola
The drainages of Angola include southern source tributaries of the Congo, western
source tributaries of the Zambezi, coastal rivers to the Atlantic from the Chiloango
in Cabinda to the Cunene in the south, and the endorheic Etosha and Okavango
Basin drainages in the south (Fig. 11.1). The watershed between the Congo system
and the coastal Atlantic and Zambezian rivers is a major ichthyofaunal divide of
considerable biogeographic significance (Poll 1967, Jubb 1967, Skelton 1994,
Snoeks et al. 2011, Paugy et al. 2017).
The freshwater fishes of Angola fall within four major African ichthyological
provinces (Fig. 11.1) – Lower Guinea, Congolese, Angolan (coastal) or Cuanza and
Zambezian (Roberts 1975, Snoeks et al. 2011, Lévêque and Paugy 2017b).
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211
Fig. 11.1 Left: Main drainage basins of Angola. A: Lower Congo, B: Cuanzan or Atlantic
Coastal, C: Cunene, D: Southwest Congo E: (west) Upper Zambezi, F: Okavango, G: Cuvelai.
Chiloango in Cabinda not illustrated. Center: Ichthyological provinces in Angola, modified from
Lévêque and Paugy (2017b) to include upper Cuanza and upper Cunene in the Zambezian Province.
A: Congolian, B: Angolan or Cuanzan, C: Zambezian. Cabinda and the Chiloango River in the
Lower Guinea Province not illustrated. Right: Aquatic ecoregions in Angola, modified, after
Thieme et al. (2005). A – Lower Congo, B – Cassai, C – Cuanza, D – Zambezian headwaters, E –
Okavango and Upper Zambezian floodplains, F – Namib coastal, G – Etosha. Southern West
Coastal Equatorial (Cabinda) not illustrated
Previously Poll (1967) considered the freshwater fishes of Angola to be from five
ichthyological regions drawn along watershed lines – Congo tributaries, Zambezi
region, Angolan (western) coastal drainages excluding the Cunene, the
Cubango-Okavango, and the Cunene. Thieme et al. (2005) defined ecoregions as “a
large area containing a distinct assemblage of natural communities and species,
whose boundaries approximate the original extent of natural communities before
major land use change”, and often reach across watershed lines. The Thieme et al.
(2005) aquatic ecoregion map for Africa included Angolan inland waters within
eight aquatic ecoregions as follows (Fig. 11.1): Floodplains, Swamps and Lakes –
Region 12 Okavango Floodplains, Region 16 Upper Zambezi Floodplains; Moist
Forest Rivers – Region 22 Lower Congo, Region 29 Southern West Coastal
Equatorial; Savannah Dry Forest – Region 63 Cuanza, Region 76 Upper Zambezian
headwaters; Xeric Systems – Region 82 Etosha, Region 88 Namib Coastal. Both the
Ichthyological Provinces and the Ecoregions are convenient categories to consider
the freshwater fishes of Angola.
Cabinda
Pellegrin (1928) recorded 28 species from the Chiloango River from Republic of
Congo (formerly ‘French’ Congo). The freshwater fishes of Lower Guinea, Central
West Africa that includes Cabinda were considered in detail through the two
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volumes edited by Stiassny et al. (2007). This rich Central West African fauna
includes 555 species in 147 genera and 38 families of which 78 species, 52 genera
and 25 families have been recorded from the Chiloango (also Shiloango) River in
Cabinda (Appendix 1). This Atlantic coastal river is clearly boosted by the large
number of marine and estuarine species that enter freshwaters sporadically or regularly (Whitfield 2007). A number of species from here such as Enteromius holotaenia, Enteromius musumbi, Aplocheilichthys spilauchen and Oreochromis angolensis,
and estuarine species of marine origin also occur in the lower reaches of Angolan
Atlantic coastal rivers, some to as far south as the Cunene River (Penrith 1982, Hay
et al. 1997). Fowler (1930) recorded a number of species in the Academy of Natural
Sciences of Philadelphia collection taken from the Chiloango region as it was
known at the time. The fauna from the Chiloango in Angolan territory is likely
underrepresented in most groups due to lack of sampling.
Lower Congo
There are no records available of fishes collected in Angolan waters of the Lower
Congo mainstream or of the southern bank tributaries. The largest of these tributaries is the Inkisi River of which the fish fauna is known from the studies of Wamuini
Lunkayilakio et al. (2010) supplemented by the description of new species described
in association with that work (Wamuini Lunkayilakio and Vreven 2008, 2010).
Based on these studies it is likely that most of the species in the DRC from the
reaches above the Sanga Falls at least are likely to occur in Angola as well. The
nature of the likely fauna of this neglected area of Angola as far as fish exploration
is concerned (Appendix 2) indicates that the species are essentially of Congolian or
Lower Guinean affinity with a few endemic species indicative of the isolation of
fauna in the river reaches above the Sanga Falls. The widespread presence of
Oreochromis niloticus is attributed to introduction for aquaculture (Wamuini
Lunkayilakio et al. 2010).
Cuanza and Atlantic Coastal Rivers
Poll (1967) listed 110 species in 32 genera and 15 families from the Atlantic coastal
region that includes the Cuanza River, which is revised (Appendix 3) to 105 species
in 45 genera and 17 families in the light of more recent surveys in the Cuanza. There
are very few species recorded from the Angolan Coastal rivers other than the
Cuanza, and in areas north of the Bengo to the mouth of the Congo records from
Angola are practically non-existent. Devaere et al. (2007) record Channallabes
apus as being described from this region. Fowler (1930) noted species of the Cuanza
and the Bengo rivers received from the British Museum on exchange, in many
instances as described by Boulenger (1910) or as recorded in Boulenger
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213
(1909–1916). Trewavas (1936) recorded and described seven species from a headwater stream of the Cuvo River arising on Mount Moco including the only Amphilius
species (Amphilius lentiginosus) described from the region. A second undescribed
Amphilius species has been recorded in the Cuanza (South African Institute for
Aquatic Biodiversity – SAIAB – collection). Both these species differ in key morphological characteristics from the Amphilius of the Zambezian region that indicate
their faunal connections lie primarily with the Lower Guinean or Congolean regions.
Trewavas (1936) also described species from the Longa (Enteromius breviceps), the
Catumbela (Enteromius dorsolineatus, E evansi), and the Balombo (Enteromius
dorsolineatus). Pellegrin (1936) described the fishes collected by two Swiss expeditions (1928–1929 and 1932) made under the direction of Monard from the Musée
d’Histoire Naturelle de la Chaux-de-Fonds included two species, Enteromius kessleri, Clarias dumerilii, that were drawn from the Cueve, with the bulk of the collections coming from the Cunene, the Cuvelai and the Cubango. Ladiges and
Voelker (1961) described Kneria maydelli from the Cunene, and Enteromius rousellei and Chiloglanis sardinhai from the Longa. Poll (1967) described Kneria sjolandersi and Chiloglanis angolensis from the Bero, to the north of the Cunene.
Trewavas (1973) recorded Oreochromis angolensis and Tilapia cabrae from the
Bengo. Bills et al. (2012) made a small collection from the upper reaches of the
Cueve River that included species of the following genera – Petrocephalus,
Enteromius, Labeobarbus, Micralestes, Amphilius, Chiloglanis, Clarias,
Pharyngochromis, Thoracochromis, Tilapia, Coptodon, and Mastacembelus. The
list is typically ‘Zambezian’ and the species positively identified are closely linked
to the upper Cuanzan and Cubango fauna. The indication from these references is
therefore that the Angolan Coastal fauna is a mix of Lower Guinean (along the
coastal plain) and Zambezian (above the escarpment) with some Congolean elements in the upper Cuanza/Lucala (see below).
The ‘Cuanzan or Angolan Coastal ’ ichthyofaunal region is drawn primarily on
what is known of the fishes of the Cuanza River as described by Boulenger (1910)
and in Boulenger’s (1909–1916) catalogue of fishes in the British Museum (Natural
History) now the Natural History Museum (NHM). Fowler’s (1930) account of the
fishes of the Gray African Expedition in 1929 included records from the Bengo and
the lower Cuanza, but also a collection of species from Chouzo on the upper reaches
of the Cutato-Cuanza tributary, that provided a first strong indication that the fauna
of these reaches is ‘Zambezian’ in character and different to those from the coastal
reaches as reported by Boulenger (1910) and others. This association was later reiterated by Trewavas (1973) when considering the cichlid species of the Cuanza and
Bengo rivers and has been firmly supported by the extensive surveys conducted by
SAIAB and INIP (Instituto Nacional de Investigação Pesqueira) between 2005 and
2010. The current assessment records at least 102 species, some of which are undescribed (Appendix 3). The collections indicate that the river basin is even more
heterogenous in fish faunal characteristics than simply ‘lower’ and ‘upper’ and the
different zones distinguishable include (1) the lower reaches from the escarpment
base to the sea, (2) the escarpment reaches, (3) the upper Cuanza and (4) the Lucala
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tributary, itself probably sub-zoned into the middle and upper reaches separated by
the Calandula Falls (formerly ‘Duque de Bragança’ Falls).
Two ecophysiological components derive the fishes of the lower Cuanza: a
diverse Tropical West African or Lower Guinean brackish water or marine
component, and secondly the primary and secondary freshwater fishes. The known
Tropical West African brackish water fishes from the system are generally widespread species and do not include endemics. Some species such as the Bull Shark
(Carcharhinus leucas) and the Atlantic Tarpon (Megalops atlanticus) are well
known as gamefish from this river. Two clupeid species include the recognised
freshwater species (Pellonula vorax and Odaxothrissa ansorgii) and probably other
brackish water forms. One haemulid (Pomadasys sp.) and one polynemid threadfin,
possibly Polydactylus quadrifilis as known from Central West Africa (Snoeks and
Vreven 2007), have been recorded (SAIAB records). Mullets (Mugilidae), as yet
unidentified at species level, are present as are the sleepers (Eleotridae) and gobies
(Awaous and Periopthalmus). Two pipefish have been positively identified:
Enneacampus ansorgii and Microphis brachyurus aculeatus. The tonguefish
Cynoglossus senegalensis was collected in the downstream reaches.
The freshwater species of this lower zone are mostly widespread species that
also occur in coastal reaches of rivers to the north, well into the adjacent Lower
Guinean Province and beyond, and many probably also to the south. An example of
this is Parailia occidentalis that has a range through to the Senegal River in West
Africa (de Vos 1995). The species that occur are found generally throughout the
region to the escarpment, with a few ascending into middle Cuanza sections. Other
characteristic species in this zone include mormyrids of the genera Hippopotamyrus,
Marcusenius and Petrocephalus, the alestid Alestes ansorgii, cyprinids of the genus
Labeo, two Enteromius species (E. holotaenia and E. musumbi), and several distinctive claroteid catfishes (two Chrysichthys species C. acutirostris and C. ansorgii), as
well as Schilbe bocagii, and the widespread Clarias gariepinus. The Chrysichthys
species confirm the West Africa coastal affinities of the assemblage as the genus is
not known from the upper reaches nor from the upper Zambezian floodplain fauna.
The cichlid fauna, as detailed systematically by Trewavas (1973) is in part also
restricted to the zone – Oreochomis angolensis, Hemichromis angolensis and
Tilapia cf. cabrae. The range of the procatopodid lampeye Aplocheilichthys
spilauchen previously known from the Senegal River to the Bengo River has been
extended to the Cuanza. The absence of the anabantid genus Ctenopoma from this
zone is remarkable.
The Escarpment Zone of the Cuanza is characterised by a stepwise series of
rapids, cascades and falls interspersed by rocky pools and runs. The fish fauna of
this important zone for hydropower development is rich but relatively poorly known
or described. The SAIAB-INIP collections are extensive and indicate that few species from the coastal zone penetrate high up into the zone. This is most probably
partly an artefact of the Cambambe Dam near the base, in existence for several
decades, which has likely affected the natural penetration of many species. The
major freshwater families are represented; the smaller cyprinids, various catfish
families, and cichlids are particularly well represented. The generic composition
11 The Freshwater Fishes of Angola
215
includes: Hippopotamyrus, Petrocephalus, Marcusenius, Parakneria, Enteromius,
Labeobarbus, Labeo, Raiamas, Brycinus, Rhabdalestes, Hepsetus, Schilbe,
Chrysichthys, Clarias, Clariallabes, Parauchenoglanis, Chiloglanis, Synodontis,
Micropanchax,
Hemichromis,
Pharyngochromis,
Pseudocrenilabrus,
Serranochromis, Tilapia, Oreochromis, and Mastacembelus. Only a single
Labeobarbus species was recorded in this zone during the survey and it also occurs
in the Lucala tributary. Boulenger (1910) recorded two Labeobarbus species from
the Cuanza at Dondo – L. rocadasi and L gulielmi. A unique morphotype of
Labeobarbus with an extremely pointed tiny mouth, collected during the Capanda
pre-impoundment surveys is present in the Luanda Museum (pers. obs., Fig. 11.2)
and is likely to be an undescribed species.
The Upper Cuanza extends from a waterfall on the mainstream above the
Capanda dam to the watershed and consists largely of relatively low-gradient floodplain rivers on Kalahari sand formations, similar to that of the upper reaches of the
Zambezi and Okavango systems in Angola. Characteristic genera from this zone
are: Hippopotamyrus, Petrocephalus, Marcusenius, Parakneria, Enteromius,
Labeobarbus, Labeo, Brycinus, Rhabdalestes, Hepsetus, Schilbe, Chrysichthys,
Doumea, Clarias, Clariallabes, Parauchenoglanis, Chiloglanis, Synodontis,
Micropanchax,
Hemichromis,
Pharyngochromis,
Pseudocrenilabrus,
Serranochromis, Tilapia, Oreochromis, and Mastacembelus. Fishes from Chouzo in
the upper Cuanza described by Fowler (1930), include species such as Marcusenius
angolensis, Hepsetus cuvieri, Labeo rocadasi, Enteromius evansi (type locality),
Enteromius lujae (identity of this species is still debated but the same species occurs
in the Okavango headwaters), Clarias gariepinus, Clarias theodorae (as C. fouloni), Clarias ngamensis (as Dinotopterus prentissgrayi), Ctenopoma machadoi
(type locality), Serranochromis macrocephalus (as Tilapia acuticeps, see Trewavas
1973). Norman (1923) described Synodontis laessoei, synonymised with Synodontis
nigromaculatus by Poll (1971), as the only species of this genus in the Cuanza, a
contrast to the specious lineage in the Okavango-Zambezi region (Day et al. 2009,
Pinton et al. 2013). Few species characteristic of the upper Cuanza are found beyond
the zone within the basin. This agrees with the notion that the fauna in this zone is
historically and biogeographically an integral part of the ‘Zambezian’ fauna
Fig. 11.2 An extraordinary undescribed Labeobarbus species from the Cuanza River in the
Luanda Museum, 2005. (Photo PH Skelton)
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P. H. Skelton
(Trewavas 1973). Ladiges (1964) and Poll (1967) showed this to be general for the
fauna as a whole, and specific studies on species like Hepsetus cuvieri (Zengeya
et al. 2011) and cichlids like Serranochromis and Tilapia sparrmanii (Musilová
et al. 2013) confirm this relationship. Recent surveys across the watershed between
the Cuanza and the Okavango indicate that a number of other species like Parakneria
fortuita, and several Enteromius species like E mocoensis, E evansi, E breviceps, E
brevidorsalis occur in streams on either side and have helped to define the Upper
Zambezi headwaters ecoregion that embraces this trans-system conformance.
An early indication that the Lucala River, a major tributary that joins the system
in the lower reaches, is exceptional for its fishes was the fauna collected by Ansorge
using a wide range of methods including explosives (Boulenger 1910). It is however
only in the escarpment and upper reaches that such exception occurs. An assemblage of large fishes of the genus Labeobarbus in particular is outstanding, and
Boulenger (1910) described 12 species now in Labeobarbus (Vreven et al. 2016),
all of which remain valid at this time. In addition to these species, unpublished barcode studies conducted by SAIAB on the fauna indicates that several lineages in the
system are restricted to the Lucala, including an Alestes, Pharyngochromis,
Serranochromis, Tilapia, two Enteromius species, a Parakneria, Hippopotamyrus,
and a undescribed Congoglanis.
The significance of the use of explosives in assembling Ansorge’s collection
described by Boulenger (1910) is that it included a number of large mainstream species that otherwise are extremely difficult to collect. The assemblage of large
Labeobarbus described in the paper has defined the Cuanza Basin since that time.
The overall faunal characteristics of the Lucala include species of the following
genera: Hippopotamyrus, Petrocephalus, Kneria, Alestes, Enteromius, Labeobarbus,
Labeo, Raiamas, Amphilius, Congoglanis, Schilbe, Clarias, Chiloglanis, Synodontis,
Micropanchax, Pharyngochromis, Serranochromis, Tilapia, and Mastacembelus.
The fauna of the upper reaches is poorly known. Only a single collection made by
SAIAB was drawn from the Lucala above the Calandula Falls. This limited sample
is not sufficient to gauge the full character of the zone, but does indicate a degree of
continuity with the Middle Lucala zone, and differing through the absence of major
elements like the Labeobarbus species so characteristic of the latter. The physical
character of the upper reaches suggests there is a zonal distinction in the ecological
character and thus the faunal elements. The known fauna includes species of the
following genera: Hippopotamyrus, Petrocephalus, Parakneria, ‘Barbus’,
Enteromius, Amphilius, Congoglanis, Clarias, Micropanchax, Pharyngochromis,
Serranochromis. Little else can be stated at this point except that an investigation
into the fauna is highly desirable given the unique nature of the Middle Lucala.
The Lucala catchment shares its watershed with tributaries of the Congo-Cuango
River and is likely one of the underlying reasons for its unique character. A high
degree of endemicity to this catchment is therefore evident and with further taxonomic investigation likely to be upheld and enhanced.
11 The Freshwater Fishes of Angola
217
Cunene
Poll (1967), from the ichthyological perspective, treated the Cunene River system
as a separate entity to the Atlantic coastal region, whereas it has been regarded as
part of the Zambezian Province by Roberts (1975), part of the ‘Angola’ ichthyofaunal province by Lévêque and Paugy (2017a, b), and divided as part of the Namib
aquatic ecoregion and part upper Zambezian headwaters ecoregions by Thieme
et al. (2005). The reason for these varied treatments is that the river system is geoeco-historically complex. Thus it has a dual geomorphological origin (the upper
reaches being a natural part of the Kalahari Basin that has been captured by an
Atlantic coastal river) and environmentally the lower reaches sit within the ‘xeric’
Namib region and the inland upper reaches within the savanna dry forest environs.
The fishes of the Cunene River are relatively well documented, starting with
Schilbe steindachneri (a synonym of S. intermedius) and Mormyrus anchietae (a
synonym of M. lacerda) described by Guimarães (1884), and summarised in the
most recent checklist by Hay et al. (1997). Excluding the more strictly marine families there are 82 species recorded from the Cunene (Appendix 3). Hay et al. (1997)
also record the broad distribution of species within the system according to three
sections, the upper reaches down to Ruacana Falls, a middle section down to Epupa
Falls and the lower river from below Epupa Falls to the mouth. Of 65 species
recorded above Ruacana Falls 13 are restricted to that section. At least one species,
Marcusenius deserti, is restricted to the lower reaches close to the coast (Kramer
et al. 2016). Apart from the several marine species recorded in the extreme lower
reaches by Penrith (1970) and Hay et al. (1997) that reflect a southernmost extension of the tropical (Lower Guinean) fauna, the general composition is clearly
Zambezian in character. There are few representatives indicative of the Angolan
(Cuanzan) Province, e.g. Enteromius mattozi (described by Guimarães (1884) from
the Curoca River to the north of the Cunene). Pellegrin’s (1921) Enteromius (formerly Barbus) rohani, probably a synonym of E. mattozi, was likely taken from the
Caculovar River, a tributary of the Cunene, and not from the Lomba (neither the
Zambezi as Pellegrin claimed, nor the Longa coastal Atlantic as suggested by Poll
1967). Enteromius argenteus is another minnow that has been reported from the
Cunene but whose identity is unconfirmed – and is likely to be juveniles of E. mattozi (Skelton Unpublished Data).
There are also several isolated endemics from the system such as Marcusenius
deserti, Marcusenius magnoculis, Marcusenius multisquamatus, Hippopotamyrus
longilateralis, Engraulicypris howesi, Zaireichthys cuneneensis, Orthochromis
machadoi, Thoracochromis albolabrus, Thoracochromis buysi, that suggests a
degree of isolation probably reflecting older biogeographic connections. The
absence of certain conspicuous families or genera such as Parakneria, Labeobarbus,
Opsaridium, Hydrocynus, Parauchenoglanis, Amphilius, Hemichromis, and
Mastacembelus is also noteworthy and perhaps indicative of a lack of more recent
connections with the Zambezian and Cuanza systems.
218
P. H. Skelton
Cassai and Southern Congo Rivers
Collections from the Lulua River, a tributary of the Cassai in Congo by Fowler
(1930) whilst not strictly in Angola, probably pertain to Angola as well. Thus
although not the only source, Poll (1967) is the current practical published source
for the fishes of the southern Congo river tributaries in Angola. There are three main
tributaries draining the region, from the east the Cassai including the Luangwe, the
Cuilu (or Kwilu) and the Cuango. Poll (1967: 18–23) plotted the records of the
fishes of each of these in his distribution table, recording 108, 28 and 37 species
respectively and in the addendum supplemented the Cassai with three species and
the Cuango with 24 species. The figure for the southern catchments of the Congo in
Angola is now estimated at around 162 species (Appendix 3). The Cuilo and Cuango
faunas are most evidently far from well explored. The Cassai fish fauna is better
represented but still poorly explored, and includes species both typical of the Congo
(e.g. Polypterus ornatipinnis, Channallabes apus, several mormyrid species,
Bryconaethiops microstoma, Alestes grandisquamis, Distichodus fasciolatus,
Distichodus lusosso, Mastacembelus congicus), and many species found also in the
Upper Zambezi or the Okavango (e.g. Hydrocynus vittatus, Hepsetus cuvieri,
Pollimyrus castelnaui, Enteromius brevidorsalis, Parauchenoglanis ngamensis,
Clarias stappersii, Clarias theodorae, Schilbe yangambianus, Micropanchax katangae, Oreochromis andersonii, Coptodon rendalli, Tilapia sparrmanii, Tilapia
ruweti, Hemichromis elongatus, Serranochromis microcephalus, Serranochromis
robustus jallae, Pseudocrenilabrus philander, Ctenopoma multispine,
Microctenopoma intermedium). The presence of Dundocharax bidentatus in the
Cassai and the rare Zambezian endemic not yet found in Angola, Neolebias lozii are
further good indicators of geographical connection. The strong Cassai-Zambezian
faunal association is attributed to the clear evidence of hydrological pattern that the
upper Cassai was formerly part of the Upper Zambezi system (Bell-Cross 1965).
Zambezian-Cuando-Cubango Headwaters and Floodplains
There is sufficient direct connection between the Zambezi, the Cuando and the
Okavango river basins and similarity of the fish faunas in each to consider these
under a single heading.
The Zambezi headwaters in Angola drain the Kalahari sand formation over an
extensive divide with the Cassai to form major floodplains known as the Bulozi
Floodplains. There are a number of lakes associated with the drainage including the
largest freshwater lake in Angola, Lake Dilolo. The Okavango drainage is divided
into two branches, the Cuito-Cuanavale in the east and the Cubango in the west. The
Cuito-Cuanavale drains Kalahari sand formations giving rise to extensive lowgradient seepage bog and floodplain rivers in slump valleys extending into miombo
savanna woodlands in the upper reaches. There are several lakes in these headwaters.
11 The Freshwater Fishes of Angola
219
The Cubango branch arises as several relatively steep gradient rocky rivers in the
Angolan highlands on the Bié plateaux before descending to the low-gradient
reaches along the Namibian border to join with the Cuito before crossing to
Botswana and forming the mostly endorheic Okavango Delta. The watershed of the
system is shared with the Cuando, the Zambezi (mainly the Lungwe-Bungo), the
Cueve-Cuanza, and the Cuanza as well as the Cunene and Cuvelai oshanas in the
west.
The fishes of the Upper Zambezi are well studied and documented (e.g. Jackson
1961, Jubb 1961, 1967, Balon 1974, Bell-Cross and Minshull 1988, Tweddle 2010)
with numbers now estimated at around 100–120 species (Appendix 3; Tweddle
et al. 2004), possibly with as many as 20–25 undescribed. However published
records from the Angolan territory are sparse, and limited in the published literature
to Poll’s (1967) 41 species (against his checklist of 62) taken mostly from two
localities close to the watershed (Lagoa Calundo and the Longa-Luena tributary).
Recent collections from the source reaches of Zambezian tributaries in Angola
made by the National Geographic Okavango Wilderness Project (NGOWP 2018)
are still being assessed but include 39 species from 12 families that have been
included in the checklist of fishes from this region (Appendix 3). One notable new
record is Enteromius chiumbeensis described by Poll (1967) from the Chiumbe
River a tributary of the Cassai, reinforcing the close connections between these
adjacent trans-watershed systems.
The upper Zambezian fish fauna is distinctive in several respects, most notably
for the relatively speciose endemic Synodontis catfishes and the serranochromine
cichlids (Trewavas 1964, Bell-Cross 1975, Greenwood 1993, Day et al. 2009;
Pinton et al. 2013). To a large extent, in Angola, the fauna is ecologically tuned to
the extensive seepage and floodplain drainages within a band of miombo savanna
woodland on Kalahari sand deposits. Overall the known Angolan Upper Zambezi
fish fauna is similar to that of the better-studied (in Angola) Okavango Basin fishes
(often with the same or closely related species e.g., mormyrids of the genera
Hippopotamyrus, Marcusenius, Petrocephalus, Pollimyrus – Kramer et al. 2003,
2004, 2012, 2014, and Zaireichthys species – Eccles et al. 2011). Whilst there are a
few endemics, only one, Paramormyrops jacksoni Poll 1967 is restricted to Angola.
The isolated Neolebias lozii is known only from the Barotse floodplains in Zambia.
Fishes of the Cuando-Linyanti-Chobe system have not been reported on from the
Angolan section of that Zambezi tributary but van der Waal and Skelton (1984)
provided a checklist of fishes in the Cuando River in Namibian waters. The 56 species recorded were all also found in the Zambezi system in Namibia. The Pallid
Sand Catlet, Zaireichthys pallidus Eccles et al. (2011) is described from the Cuando
but is not restricted to that system. Kramer et al. (2014) described a new species of
Pollimyrus from the Cuando, a species possibly endemic to that tributary. Recent
collections by the National Geographic Okavango Wilderness Project (NGOWP/
SAIAB) from the upper reaches of the Cuando in Angola further inform the list of
species (Appendix 3).
The fishes of the Okavango Basin have been studied and reported on in the literature for over 150 years since Castelnau (1861) described 14 species from Lake
220
P. H. Skelton
Ngami, including the iconic Tigerfish (Hydrocynus vittatus) the Southern African
Pike (Hepsetus cuvieri), the large Blunttooth Catfish (Clarius ngamensis) and the
Three Spot Bream (Oreochromis andersonii). Fifty years later Boulenger (1911)
reported on a collection from the Okavango-Lake Ngami made by RB Woosnam
and described six new species including one named for Castelnau – Pollimyrus
castelnaui. These fishes were all included in Gilchrist and Thompson (1913, 1917)
and Boulenger (1909–1916). Fowler (1935) described a collection made from the
Delta by the Vernay-Lang Expedition of 1930. Pellegrin (1936) described fishes
collected by two Swiss expeditions of 1929 and 1933 from the Cunene, the Cuvelai
and the Cubango. Barnard (1948) described in detail a collection from Rundu,
Namibia. The results of all these efforts were summarised in checklists published by
Poll (1967), Jubb (1967), Jubb and Gaigher (1971) and Skelton et al. (1985). More
recently surveys of Angolan Okavango Basin rivers have been made (Bills et al.
2012, 2013, Skelton et al. 2016) that have reached little-explored areas, encountered
additional species and provide for a more complete assessment of the fishes and
their intra-basin distributions.
The additional species recently discovered include new species of Clariallabes,
several serranochromine cichlids, and a dwarf climbing perch (Microctenopoma
sp). Recent distribution records extend the range of several species from the Congo
tributaries or in the case of Clypeobarbus bellcrossi from Zambezi headwaters in
Zambia to the Okavango. Congolean species such as Marcusenius moorii (Günther)
and Enteromius chicapaensis (Poll), and Nannocharax lineostriatus (Poll), and several Micropanchax as M. luluae, M. nigrolateralis, M. lineolateralis. The known
range of a number of species from the Atlantic Coastal and Cuanza systems has
been extended to the Okavango, e.g. Enteromius breviceps, E. brevidorsalis, E.
evansi, E. mocoensis, E. greenwoodi. A new understanding of the complex distribution of the twin species Enteromius trimaculatus and E. poechii has also been
reached – the former being found in the Cunene and the extreme upper reaches of
the Cubango in place of the latter which is widespread in the downstream floodplain
reaches of the Okavango and Upper Zambezi system.
Cuvelai
The Cuvelai drainage lies in a triangle between the Okavango in the east and the
Cunene in the west and the streams known as ‘iishanas’ are intermittent, only flowing during periods of sustained rainfall into the endorheic Etosha Pan in Namibia
(van der Waal 1991, Hipondoka et al. 2018). The 1929 and 1932–1933 Swiss expeditions to Angola collected the following species from Mupa (Pellegrin 1936):
Marcusenius altidorsalis (?), Mormyrus lacerda, Enteromius paludinosus, Tilapia
sparrmanii, and Pseudocrenilabrus philander. Seventeen species, all conforming to
Cunene fauna, have been confirmed from the western iishanas of the system by
Hipondoka et al. (2018), and connections with the Cunene substantiated through
remote sensing techniques. Four widespread pioneering species are consistently
11 The Freshwater Fishes of Angola
221
present in collections, viz., Clarias gariepinus, Enteromius paludinosus,
Oreochromis andersonii and Pseudocrenilabrus philander and several others are
common – Clarias ngamensis, Schilbe intermedius and Enteromius trimaculatus.
Biogeography
The biogeography of Angolan freshwater fishes is closely tied to the geomorphology and the geomorphological history of the territory. In brief, Angola consists of a
narrow coastal plain, a distinct escarpment and an interior plateau that is being
eroded most rapidly from the Congo Basin. The coastal plain consists of a series of
rivers flowing from the escarpment or – in the case of the Congo in the north, the
Cuanza in the middle and the Cunene in the south – where the escarpment has been
penetrated, from the interior plateau or the Congo Basin. The fish fauna of the
coastal plain is primarily a southern extension of the tropical coastal fauna of West
Africa and Central West Africa. River connections along this narrow strip are either
via sea-level fluctuations or via river captures between watersheds, either as adjacent systems or via extended reaches through captured inland drainages that are not
determined by the coastal gradients and processes. According to Lévêque and Paugy
(2017a,b) the primary direction of dispersal of the coastal west African fauna was
northwards from the Congo. Present day ocean currents off Angola are counter
clockwise (http://oceancurrents.rsmas.miami.edu) and it is possibly only inshore
counter currents that might have facilitated faunal dispersal southwards from the
Congo, especially after the capture and penetration of the Congo Basin by the Lower
Congo in the late Cretaceous (Flügel et al. 2015). Such would certainly explain
much of the marine derived elements of the region. Given favourable currents it is
likely also that the considerable volumes of freshwater entering the sea from the
Congo at various times would facilitate even freshwater fishes down the coast and
might explain the presence of such species as Enteromius musumbi, Physailia occidentalis, Chysichthys spp, Oreochromis angolensis and Aplocheilichthys spilauchen
in the Angolan region. An alternative and complementary explanation for some
freshwater faunal elements such as Marcusenius deserti and Raiamas ansorgii of
the Angolan Coastal reaches is that it is primarily derived via the Cuanzan and
Cunene gateways through capture of portions of the Kalahari Basin drainage. It is
not only the Cuanza and the Cunene that have breached the escarpment but also the
Cuvo and the Longa and possibly others, as is evident in the list of freshwater fishes
reported from these lesser rivers (see above).
The evolution of the extensive Kalahari Basin is certainly key to understanding
the majority of the freshwater fish fauna of Angola. Haddon and McCarthy (2005),
Key et al. (2015), Moore and Larkin (2001), and Moore et al. (2012) sketch the
evolution of the Kalahari Basin and its drainage since the breakup of Gondwanaland
and the isolation of Africa in the late Cretaceous. Following rifting, the continental
margins were probably elevated and this formed an escarpment that separated the
narrow coastal plain from the elevated Kalahari sedimentary basin that was drained
222
P. H. Skelton
primarily by the palaeo-upper Zambezi, the predominant system in the Angolan
region (Fig. 11.3). The western portion of the system flowed from the escarpment
highlands of the extreme northwest of the basin, now part of the Cuanza, generally
southeast through the Limpopo valley to the Indian Ocean. The eastern parts of the
upper Zambezi reached northeastwards to as far as pre-rift East African plateaus and
Fig. 11.3 A diagrammatic model for the post-Cretaceous biogeography of Angolan freshwater
fishes. Angolan border – fine dotted line; present day drainage – thin lines; present day inter basin
watersheds – open dotted lines; paleo drainage lines – thick extended arrows; paleo and present
escarpment retreat – dashed arrows; paleo and present south and southwestern Congo Basin watershed – thick dashed lines; Angolan escarpment – right slanted hash; gateway drainage captures –
large open bi-directional arrows. Coastal dispersal of fishes – large left-slanted bi-directions arrow.
The model is based on geomorphological interpretations by Flügel et al. (2015), Haddon and
McCarthy (2005), Moore and Larkin (2001), Moore et al. (2012), and others
11 The Freshwater Fishes of Angola
223
included the proto-Luangwa and the proto-Chambeshi-Kafue-upper Zambezi as
well as the Okavango. These drained into an interior basin to form, at times, a mega
palaeo lake – Palaeolake Magadigadi (Burroughs et al. 2009, Moore and Larkin
2001, Moore et al. 2012, Podgorski et al. 2013). The proto-Cunene consisted of an
upper portion draining endorheically to the Etosha basin. The most significant
events in the history of the Kalahari Basin were firstly the downwarping and backtilting of drainage coupled with upwarping along the southern margins that severed
the initial Indian Ocean outlet via the Limpopo; the tapping of the Congo Basin by
the lower Congo River that advanced the erosion and southern retreat of the northern watershed of the basin, especially in the northeast (Luapula-Chambeshi) and, in
the Angola area, the Cassai-Zambezi. The dismemberment and tapping of drainage
portions from the Kalahari Basin to coastal outlets including the Cuanza, the
Cunene, and the Zambezi also affects the biogeographical history significantly
(Moore and Larkin 2001, Moore et al. 2012, Key et al. 2015).
The most profound biogeographic significance to emerge from this geomorphological narrative is that the Kalahari Basin has been an evolutionary basin for fishes
over a long period of time. The evidence is exemplified in the serranochromine
cichlid radiation and the clade of Synodontis catfish and the radiation of several
mormyrid genera that characterise the Zambezian fauna (Bell-Cross 1975,
Greenwood 1984, Kramer et al. 2003, 2004, Day et al. 2009, Kramer and Swartz
2010, Kramer et al. 2012, Schwarzer et al. 2012, Pinton et al. 2013, Kramer and
Wink 2013). The strong identity of the upper Zambezian fauna further exemplifies
this notion. That the fauna has been supplemented with species from neighbouring
ichthyological provinces, especially the Congo, is also evident in species or genera
with internally restricted distributions such as Hepsetus cuvieri, Hydrocynus
vittatus, Parauchenoglanis ngamensis, Mastacembelus, Hemichromis elongatus,
Amphilius and others. The broader distributions of some species into basins like
the east coast rivers (e.g. Enteromius bifrenatus, Microctenopoma intermedium,
Clarias theodorae, Brycinus lateralis) gives biological credence to the former east
coast linkage and subsequent drainage dismemberment on the proto-upper Zambezi
(Skelton 1994, 2001).
There are other emerging details of biogeographical interest to Angola that will
in time lead to a detailed accounting of the origins and development of the freshwater fishes. Thus the presence of doumeine catfishes in the Cuanza, southwest of the
Congo, indicates clearly insemination from the Congo. The flock of Labeobarbus
species in the Lucala-Cuanza probably also indicates a Congolian insemination.
However the assumption that all traffic was from the Congo is not necessarily correct and Neolebias bidentatus in the Cassai, for example, as with other ‘Zambezian’
elements in that system, more likely reflects a Zambezian (i.e. Kalahari) insemination to the Congo. This, in essence, is the basis of the ‘Upper Zambezi headwater’
freshwater ecoregion (Fig. 11.1: basin C).
224
P. H. Skelton
Conservation
Angola is an emerging African economy with a rapidly growing human population
and increasing demand on freshwater resources. The rapid population growth and
expansion of urban areas in places such as Luanda but also in the more rural districts
(Mendelsohn and Weber 2015) is placing an ever increasing stress on the environment, especially that of the rivers for which such urban growth centres are dependent on for water and power. Although many Angolan rivers are relatively
unregulated there are dams on several systems such as the three major hydroelectric
dams on the Cuanza. A further four hydroelectric dams are planned for the escarpment section of this system alone. In the case of certain transboundary rivers like the
Okavango, the threat of increased river regulation is of serious concern to the integrity of the Okavango Delta in Botswana, a World Heritage and Ramsar site (King
and Chonguic 2016).
Diamond mining activities along the southern Congo tributaries have had environmental impacts of unknown severity as practically no public investigations or
information is available.
With human populations, urbanisation and development comes pollution and
other direct threats to aquatic life such as fishing and the introduction of invasive
alien species. Few alien fishes have been recorded from Angola, but two species that
have been introduced are Oreochromis mossambicus (SAIAB, in the Cuanza) and
Oreochromis niloticus in Cabinda and, as recently confirmed, in the upper Cubango.
The threats these particular species pose as aliens is well documented (e.g. Wise
et al. 2007, Zengeya et al. 2013, Bbole et al. 2014). This is the first record of an alien
species with high impact potential in the Okavango system and the threat posed is
transboundary in nature. Potential transboundary threats from outside Angola
include that of alien crayfish from the Zambezi (Nunes et al. 2016).
Indigenous fishery practices in Angola include a range of gear ranging from simple traps to elaborate fishing fences and walls (Poll 1967, Mendelsohn and Weber
2015). In places such traditional practices are still in evidence (Fig. 11.4 top), but
elsewhere traditional practices are being replaced by modern gear such as monofilament gillnets and mosquito-net seines (Fig. 11.4 bottom) that are excessively
destructive and unsustainable (Tweddle et al. 2015).
The current IUCN redlist assessments for Angolan freshwater fishes (Appendix
3) reflects the relatively weak knowledge of the species – a third of the known species are either not assessed or are Data Deficient (DD). One species (Oreochromis
lepidurus) is listed as Endangered (see Moelants 2010), three are Vulnerable (1%)
and 185 (65%) are Least Concern. The endangered species is a Lower Congo
endemic found mainly in the DRC and is primarily threatened by oil pollution
derived from boats. The Vulnerable species are also cichlids of the genus
Oreochromis – O. andersonii (see Marshall and Tweddle 2007) and O. macrochir
(see Marshall and Tweddle 2007), both are threatened through hybridisation from
the alien invasive species Oreochromis niloticus. The latter species has recently
been confirmed as present in Angola, within the Okavango catchment and its impact
11 The Freshwater Fishes of Angola
225
Fig. 11.4 Top – traditional fishing fence on the Cacuchi River, 2012 (Photo PH Skelton). Bottom –
Drying fish caught with monofilament gillnets on the Cuito River, 2015. (Photo G Neef)
226
P. H. Skelton
on the native Oreochromis is now an imminent threat. Given the situation of rapidly
escalating changes to the natural aquatic environment in Angola it is likely that the
IUCN redlist score for the country will rise rapidly.
Acknowledgements I am supported in my research by the Director and staff of SAIAB, in particular Roger Bills and members of the collections division, administration staff, and by Maditaba
Meltaf in the library for the provision of literature. Steve Boyes and John Hilton of the Wild Bird
Trust have provided me with excellent opportunity to study fishes in Angola since 2015. I have
been supported in the field and laboratory by Adjani Costa, Roger Bills, Ben van der Waal, Götz
Neef and others of the National Geographic Okavango Wilderness Project. SAIAB engagement
with Angolan fishes was initiated in 2005 in partnership with INIP (Instituto Nacional de
Investigação Pesqueira). Ernst R Swartz (SAIAB) and D Neto (INIP) were instrumental in opening
the channels of new knowledge on Angolan freshwater fishes.
Appendices
Appendix 1
Freshwater and brackish water fishes of Shiloango River, Cabinda, as recorded by
Stiassny et al. (2007)
Species
Clupeidae
Pellonula vorax
Mormyridae
Isichthys henryi
Marcusenius moorii
Paramormyrops kingsleyae
Brienomyrus brachyistius
Hepsetidae
Hepsetus lineatus
Alestidae
Brycinus longipinnis
Brycinus macrolepidotus
Brycinus kingsleyae
Nannopetersius ansorgii
Distichodontidae
Distichodus notospilus
Eugnathichthys macroterolepis
Nannaethiops unitaeniatus
Nannocharax parvus
Neolebias ansorgii
Neolebias spilotaenia
Author & Date
Günther, 1868
Gill, 1863
Günther, 1863
(Günther, 1863)
(Gill, 1862)
(Pellegrin, 1926)
(Günther, 1864)
Valenciennes, 1850
(Günther, 1896)
(Boulenger, 1910)
Günther, 1867
Boulenger, 1899
Günther, 1872
Pellegrin, 1906
Boulenger, 1912
Boulenger, 1912
(continued)
11 The Freshwater Fishes of Angola
Species
Cyprinidae
Enteromius carens
Enteromius jae
Enteromius guirali
Enteromius callipterus
Enteromius camptacanthus
Enteromius rubrostigma
Enteromius holotaenia
Labeobarbus aspius
Labeobarbus cardozoi
Labeobarbus roylii
Labeobarbus batesii
Labeobarbus sandersi
Labeo batesii
Labeo lukulae
Opsaridium ubangiense
Ariidae
Arius latiscutatus
Claroteidae
Anaspidoglanis macrostoma
Parauchenoglanis altipinnis
Chrysichthys auratus
Chrysichthys nigrodigittatus
Schilbeidae
Parailia occidentalis
Pareutropius debauwi
Clariidae
Clarias angolensis
Clarias gabonensis
Malapteruridae
Malapterurus beninensis
Procatopodidae
Aplocheilichthys spilauchen
Plataplochilus loemensis
Nothobranchiidae
Epiplatys singa
Aphyosemion escherischi
Anabantidae
Ctenopoma nigropannosum
Microctenopoma ansorgii
Microctenopoma nanum
Microctenopoma congicum
227
Author & Date
(Boulenger, 1912)
(Boulenger, 1903)
(Thominot, 1886)
(Boulenger, 1907)
(Bleeker, 1863)
(Poll & Lambert, 1964)
(Boulenger, 1904)
(Boulenger, 1912)
(Boulenger, 1912)
(Boulenger, 1912)
(Boulenger, 1903)
(Boulenger, 1912)
Boulenger, 1911
Boulenger, 1902
(Pellegrin, 1901)
Günther, 1864
(Pellegrin, 1909)
(Boulenger, 1911)
(Geoffroy Saint-Hilaire, 1809)
(Lacépède, 1803)
(Pellegrin, 1901)
(Boulenger, 1900)
Steindachner, 1866
Günther, 1867
Murray, 1855
(Duméril, 1861)
(Pellegrin, 1924)
(Boulenger, 1899)
(Ahl, 1924)
Reichenow, 1875
(Boulenger, 1912)
(Günther, 1896)
(Boulenger, 1887)
(continued)
228
Species
Cichlidae
Pelvicachromis subocellatus
Chilochromis duponti
Coptodon tholloni
Pelmatolapia cabrae
Coptodon guineensis
Oreochromis schwebischi
Sarotherodon nigripinnis
Lutjanidae
Lutjanus dentatus
Monodactylidae
Monodactylus sebae
Polynemidae
Polydactylus quadrifilis
Mugilidae
Mugil bananensis
Neochelon falcipinnis
Chelon dumerili
Eleotridae
Eleotris daganensis
Eleotris senegalensis
Eleotris vittata
Bostrychus africanus
Dormitator lebretonis
Gobiidae
Periopthalmus barbarus
Gobionellus occidentalis
Bathygobius soporator
Bathygobius casamancus
Nematogobius maindroni
Microdesmidae
Microdesmus aethiopicus
Mastacembelidae
Mastacembelus shiloangoensis
Mastacembelus niger
Syngnathidae
Enneacampus ansorgii
Microphis aculeatus
Cynoglossidae
Cynoglossus senegalensis
Citharichthys stampflii
P. H. Skelton
Author & Date
(Günther, 1872)
Boulenger, 1902
(Sauvage, 1884)
(Boulenger, 1899)
(Günther, 1862)
(Sauvage, 1884)
(Guichenot, 1861)
(Duméril, 1861)
(Cuvier, 1829)
(Cuvier, 1829)
(Pellegrin, 1927)
(Valenciennes, 1836)
(Steindachner, 1870)
Steindachner, 1870
Steindachner, 1870
Duméril, 1861
(Steindachner, 1879)
(Steindachner, 1870)
(Linnaeus, 1766)
(Boulenger, 1909)
(Valenciennes, 1837)
(Rochebrune, 1880)
(Sauvage, 1880)
(Chabanaud, 1927)
(Vreven, 2004)
Sauvage, 1879
(Boulenger, 1910)
(Kaup, 1856)
(Kaup, 1858)
(Steindachner, 1894)
11 The Freshwater Fishes of Angola
229
Appendix 2
Freshwater fishes of the Inkisi River DRC, from above the Sangha waterfalls, after
Wamuini Lunkayilakio et al. (2010)
Species
Mormyridae
Hippopotamyrus cf. ansorgii
Paramormyrops cf. kingsleyae
Paramormyrops cf. sphekodes
Cyprinidae
Enteromius miolepis
Enteromius unitaeniatus
Enteromius vandersti
Garra congoensis
Labeo macrostomus
Labeobarbus sp. nov.
Labeobarbus boulengeri
Labeobarbus robertsi
Raiamas kheeli
Alestidae
Nannopetersius mutambuei
Claroteidae
Parauchenoglanis balayi
Clariidae
Clarias angolensis
Clarias buthupogon
Clarias camerunensis
Clarias gariepinus
Clarias gabonensis
Schilbeidae
Schilbe zairensis
Cichlidae
Haplochromis snoeksi
Hemichromis elongatus
Oreochromis niloticus
Sarotherodon galilaeus
Coptodon tholloni
Anabantidae
Ctenopoma nigropannosum
Chanidae
Parachanna obscura
Author & Date
(Boulenger, 1905)
(Günther, 1896)
(Sauvage, 1879)
(Boulenger, 1902)
(Günther, 1867)
(Poll, 1945)
Poll, 1959
Boulenger, 1898
Vreven, Musschoot, Snoeks & Schliewen, 2016
(Banister, 1984)
Stiassny, Schelly & Schliewen, 2006
Wamuini Lunkayilakio & Vreven, 2008
(Sauvage, 1879)
Steindachner, 1866
Sauvage, 1879
Lönnberg, 1895
(Burchell, 1822)
Günther, 1867
de Vos, 1995
Wamuini Lunkayilakio & Vreven, 2010
(Guichenot, 1861)
(Linnaeus, 1758)
(Linnaeus, 1758)
(Sauvage, 1884)
Reichenow, 1875
(Günther, 1861)
230
P. H. Skelton
Appendix 3
Freshwater fishes of the (A) Cuanza (Atlantic coastal), (C) southern Congo, (Z)
Upper Zambezian, (O) Okavango, and (K) Cunene basins in Angola, after Poll
(1967) with updated adjustments for taxonomy and known records by the author
Species
Protopteridae
Protopterus aethiopicus
Protopterus dolloi
Polypteridae
Polypterus ornatipinnis
Clupeidae
Pellonula vorax
Odaxothrissa ansorgii
Kneriidae
Kneria angolensis
Kneria maydelli
Kneria polli
Kneria sjolandersi
Kneria ansorgii
Parakneria marmorata
Parakneria vilhenae
Parakneria fortuita
Mormyridae
Mormyrops attenuatus
Mormyrops anguilloides
Petrocephalus okavagoensis
Petrocephalus magnitrunci
Petrocephalus magnoculis
Petrocephalus longicapitis
Petrocephalus christyi
Petrocephalus cunganus
Petrocephalus micropthalmus
Petrocephalus simus
Hippopotamyrus ansorgii
Hippopotamyrus
longilateralis
Pollimyrus brevis
Pollimyrus castelnaui
Pollimyrus cuandoensis
Pollimyrus marianne
Cyphomyrus cubangoensis
Author & Date
A
C
Z
O
K
Ia
Heckel, 1851
Boulenger, 1900
x
x
DD
LC
Boulenger, 1902
x
LC
LC
LC
Günther, 1868
Boulenger, 1910
x
x
x
x
Steindachner, 1866
Ladiges & Voelker, 1961
Trewavas, 1936
Poll, 1967
(Boulenger, 1910)
(Norman, 1923)
Poll, 1965
Penrith, 1973
x
x
Boulenger, 1898
(Linnaeus, 1758)
Kramer et al., 2012
Kramer et al., 2012
Kramer et al., 2012
Kramer et al., 2012
Boulenger, 1920
Boulenger, 1910
Pellegrin, 1909
Sauvage, 1879
(Boulenger, 1905)
Kramer & Swartz, 2010
(Boulenger, 1913)
(Boulenger, 1911)
Kramer, van der Bank &
Wink, 2013
Kramer et al., 2003
(Pellegrin, 1936)
?
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
?
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
LC
LC
LC
DD
DD
DD
DD
DD
LC
LC
NE
NE
NE
NE
NE
DD
LC
LC
LC
NE
LC
LC
NE
NE
NE
(continued)
11 The Freshwater Fishes of Angola
Species
Cyphomyrus psittacus
Paramormyrops jacksoni
Marcusenius altisambesi
Hippopotamyrus pappenheimi
Heteromormyrus
pauciradiatus
Pollimyrus tumifrons
Marcusenius desertus
Marcusenius multisquamatus
Marcusenius angolensis
Marcusenius cuangoanus
Marcusenius dundoensis
Marcusenius moorii
Marcusenius stanleyanus
Campylomormyrus alces
Campylomormyrus cassaicus
Campylomormyrus elephas
Campylomormyrus numenius
Campylomormyrus
luapulaensis
Campylomormyrus
rhynchophorus
Campylomormyrus tshokwe
Gnathonemus barbatus
Gnathonemus petersii
Mormyrus caballus
Mormyrus lacerda
Mormyrus rume
Cyprinidae
Garra dembeensis
Clypeobarbus bellcrossi
Coptostomabarbus wittei
Enteromius afrovernayi
Enteromius amphigramma
Enteromius ansorgii
Enteromius argenteus
Enteromius barotseensis
Enteromius barnardi
Enteromius bifrenatus
Enteromius breviceps
Enteromius brevidorsalis
Enteromius brevilateralis
Enteromius caudosignatus
Author & Date
(Boulenger, 1897)
(Poll, 1967)
Kramer et al., 2007
(Boulenger, 1910)
(Steindachner, 1866)
(Boulenger, 1902)
Kramer, vanderBank &
Wink, 2016
Kramer & Wink, 2013
(Boulenger, 1905)
(Poll, 1967)
(Poll, 1967)
(Günther, 1867)
(Boulenger, 1897)
(Boulenger, 1920)
(Poll, 1967)
(Boulenger, 1898)
(Boulenger, 1898)
(David & Poll, 1937)
231
A
C
x
x
Z
O
x
x
x
K
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
Ia
LC
DD
LC
LC
DD
NE
NE
NE
LC
VU
DD
LC
LC
LC
DD
LC
LC
DD
(Boulenger, 1898)
x
LC
(Poll, 1967)
Poll, 1967
(Günther, 1862)
Boulenger, 1898
Castelnau, 1861
Valenciennes, 1847
x
x
x
x
LC
DD
LC
NE
LC
NE
(Rüppell, 1835)
(Jubb, 1965)
David & Poll, 1937
(Nichols & Boulton, 1927)
(Boulenger, 1903)
(Boulenger, 1904)
(Günther, 1868)
(Pellegrin, 1920)
(Jubb, 1965)
(Fowler, 1935)
(Trewavas, 1936)
(Boulenger, 1915)
(Poll, 1967)
(Poll, 1967)
x
x
x
x
x
x
x
x
x
x
x
x
x
x
LC
DD
LC
LC
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
LC
LC
LC
LC
LC
LC
LC
DD
DD
(continued)
x
x
x
x
x
x
232
Species
Enteromius chicapaensis
Enteromius chiumbeensis
Enteromius dorsolineatus
Enteromius eutaenia
Enteromius evansi
Enteromius fasciolatus
Enteromius greenwoodi
Enteromius haasianus
Enteromius holotaenia
Enteromius kerstenii
Enteromius kessleri
Enteromius lineomaculatus
Enteromius lujae
Enteromius machadoi
Enteromius mattozi
Enteromius mediosquamatus
Enteromius miolepis
Enteromius mocoensis
Enteromius multilineatus
Enteromius musumbi
Enteromius paludinosus
Enteromius petchkovski
Enteromius poechii
Enteromius radiatus
Enteromius rousellei
Enteromius thamalakanensis
Enteromius trimaculatus
Enteromius unitaeniatus
Enteromius cf viviparus
Enteromius wellmani
Labeobarbus caudovittatus
Labeobarbus codringtonii
Labeobarbus ensis
Labeobarbus gulielmi
Labeobarbus girardi
Labeobarbus jubbi
Labeobarbus lucius
Labeobarbus marequensis
(Cassai)
Labeobarbus nanningsi
Labeobarbus rhinophorus
Labeobarbus rocadasi
Labeobarbus rosae
P. H. Skelton
Author & Date
(Poll, 1967)
(Pellegrin, 1936)
(Trewavas, 1936)
(Boulenger, 1904)
(Fowler, 1930)
(Günther, 1868)
(Poll, 1967)
(David, 1936)
(Boulenger, 1904)
(Peters, 1868)
(Steindachneri, 1866)
(Boulenger, 1903)
(Boulenger, 1913)
(Poll, 1967)
(Guimarães, 1884)
(Poll, 1967)
(Boulenger, 1902)
(Trewavas, 1936)
(Worthington, 1933)
(Boulenger, 1910)
(Peters, 1852)
(Poll, 1967)
(Steindachneri, 1911)
(Peters, 1853)
(Ladiges & Voelker, 1961)
(Fowler, 1935)
(Peters, 1852)
(Günther, 1867)
(Weber, 1897)
(Boulenger, 1911)
(Boulenger, 1902)
(Boulenger, 1908)
(Boulenger, 1910)
(Boulenger, 1910)
(Boulenger, 1910)
(Poll, 1967)
(Boulenger, 1910)
(Smith, 1841)
de Beaufort, 1933
(Boulenger, 1910)
(Boulenger, 1910)
(Boulenger, 1910)
A
x
x
x
x
x
x
x
x
x
x
C
x
x
Z
O
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
?
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
K
x
x
Ia
LC
LC
LC
DD
LC
LC
DD
LC
LC
LC
LC
LC
DD
DD
LC
DD
LC
DD
LC
LC
LC
DD
LC
LC
DD
LC
LC
LC
NE
DD
LC
LC
LC
DD
DD
DD
DD
LC
DD
DD
DD
DD
(continued)
11 The Freshwater Fishes of Angola
Species
Labeobarbus ansorgii
Labeobarbus ensifer
Labeobarbus boulengeri
Labeobarbus macrolepidotus
Labeobarbus steindachneri
Labeobarbus stenostomata
Labeobarbus varicostoma
Labeo annectens
Labeo ansorgii
Labeo chariensis
Labeo cylindricus
Labeo greeni
Labeo lineatus
Labeo longipinnis
Labeo macrostoma
Labeo parvus
Labeo rocadasi
Labeo ruddi
Labeo velifer
Labeo weeksii
Engraulicypris howesi
Opsaridium zambezense
Raiamas ansorgii
Raiamas christyi
Hepsetidae
Hepsetus cuvieri
Alestidae
Bryconaethiops microstoma
Alestes macropthalmus
Brycinus kingsleyae
Brycinus grandisquamis
Brycinus humilis
Brycinus imberi
Brycinus lateralis
Micralestes acutidens
Micralestes argyrotaenia
Micralestes humilis
Nannopetersius ansorgii
Rhabdalestes maunensis
Hydrocynus vittatus
Distichodontidae
Distichodus fasciolatus
Distichodus lusosso
Distichodus maculatus
Author & Date
(Boulenger, 1906)
(Boulenger, 1910)
Vreven et al., 2016
(Pellegrin, 1928)
(Boulenger, 1910)
(Boulenger, 1910)
(Boulenger, 1910)
Boulenger, 1903
Boulenger, 1907
Pellegrin, 1904
Peters, 1852
Boulenger, 1902
Boulenger, 1898
Boulenger, 1898
Boulenger, 1898
Boulenger, 1902
Boulenger, 1907
Boulenger, 1907
Boulenger, 1898
Boulenger, 1909
Ridden, Bills & Villet, 2016
(Peters, 1852)
(Boulenger, 1910)
(Boulenger, 1920)
(Castelnau, 1861)
Günther, 1873
Günther, 1867
(Günther, 1896)
(Boulenger, 1899)
(Boulenger, 1905)
(Peters, 1852)
(Boulenger, 1900)
(Peters, 1852)
Trewavas, 1936
Boulenger, 1899
(Boulenger, 1910)
(Fowler, 1935)
Castelnau, 1861
Boulenger, 1898
Schilthuis, 1891
Boulenger, 1898
233
A
x
x
x
C
Z
O
K
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
?
x
x
x
x
x
x
x
x
x
x
x
x
x
?
x
x
x
x
x
x
x
x
x
x
x
x
x
x
NE
x
LC
LC
LC
LC
DD
LC
LC
LC
LC
LC
LC
LC
LC
x
x
x
x
x
x
x
x
x
x
x
Ia
LC
LC
NE
LC
LC
DD
DD
LC
LC
LC
LC
LC
LC
LC
LC
LC
LC
LC
NE
LC
NE
LC
DD
LC
x
LC
LC
LC
(continued)
234
Species
Distichodus notospilus
Distichodus sexfasciatus
Nannocharax macropterus
Nannocharax procatopus
Nannocharax angolensis
Nannocharax lineostriatus
Nannocharax machadoi
Nannocharax multifasciatus
Dundocharax bidentatus
Claroteidae
Chrysichthys ansorgii
Chrysichthys bocagii
Chrysichthys cranchii
Chrysichthys delhezi
Chrysichthys macropterus
Chrysichthys nigrodigitatus
Parauchenoglanis ngamensis
Amphiliidae
Zaireichthys dorae
Zaireichthys flavomaculatus
Zaireichthys pallidus
Zaireichthys conspicuus
Zaireichthys kavangoensis
Zaireichthys kunenensis
Congoglanis alula
Doumea angolensis
Congoglanis howesi
Congoglanis sp.
Amphilius lentiginosus
Amphilius cubangoensis
Phractura macrura
Phractura scaphyrhynchura
Malapteruridae
Malapterurus monsembeensis
Clariidae
Heterobranchus longifilis
Channallabes apus
Clarias angolensis
Clarias buthupogon
P. H. Skelton
Author & Date
Günther, 1867
Boulenger, 1897
Pellegrin, 1926
Boulenger, 1920
(Poll, 1967)
(Poll, 1967)
(Poll, 1967)
Boulenger, 1923
Poll, 1967
A
Boulenger, 1910
Boulenger, 1910
(Leach, 1818)
Boulenger, 1899
Boulenger, 1920
(Lacepède, 1803)
(Boulenger, 1911)
x
x
(Poll, 1967)
(Pellegrin, 1926)
Eccles, Tweddle & Skelton,
2011
Eccles, Tweddle & Skelton,
2011
Eccles, Tweddle & Skelton,
2011
Eccles, Tweddle & Skelton,
2011
(Nichols & Griscom, 1917)
Boulenger, 1906
Vari, Ferraris & Skelton,
2012
Trewavas, 1936
Pellegrin, 1936
Poll, 1967
(Vaillant, 1886)
Z
O
x
x
x
x
x
x
x
x
K
x
x
x
x
x
x
DD
DD
NE
x
x
NE
x
NE
x
x
x
x
x
x
x
x
x
x
NE
DD
NE
DD
LC
x
LC
x
x
x
x
LC
LC
LC
LC
(continued)
?
x
x
x
NE
LC
LC
NE
x
x
x
Ia
LC
LC
LC
LC
LC
DD
LC
DD
DD
LC
LC
LC
LC
DD
LC
LC
x
x
x
Roberts, 2000
Valenciennes, 1840
(Günther, 1873)
Steindachner, 1866
Sauvage, 1879
C
x
x
x
x
x
x
x
11 The Freshwater Fishes of Angola
Species
Clarias dumerilii
Clarias platycephalus
Clarias gariepinus
Clarias ngamensis
Clarias nigromarmoratus
Clarias stappersii
Clarias liocephalus
Clarias theodorae
Clariallabes heterocephalus
Clariallabes variabilis
Clariallabes platyprosopos
Clariallabes sp
Platyclarias machadoi
Schilbeidae
Parailia occidentalis
Schilbe intermedium
Schilbe angolensis
Schilbe ansorgii
Schilbe bocagii
Schilbe grenfelli
Schilbe yangambianus
Mochokidae
Synodontis laessoei
Synodontis leopardinus
Synodontis longirostris
Synodontis macrostigma
Synodontis macrostoma
Synodontis nigromaculatus
Synodontis ornatipinnis
Synodontis thamalakanensis
Synodontis woosnami
Synodontis vanderwaali
Chiloglanis angolensis
Chiloglanis fasciatus
Chiloglanis lukugae
Chiloglanis micropogon
Chiloglanis sardinhai
Euchilichthys astatodon
Euchilichthys royauxi
Atopochilus macrocephalus
Chiloglanis sp. (dark)
Chiloglanis sp. (gold)
Author & Date
Steindachner, 1866
Boulenger, 1902
(Burchell, 1822)
Castelnau, 1861
Poll, 1967
Boulenger, 1915
Boulenger, 1898
Weber, 1897
Poll, 1967
Pellegrin, 1926
Jubb, 1965
235
A
x
x
x
x
Poll, 1977
(Pellegrin, 1901)
Rüppell, 1832
(De Vos, 1984)
(Boulenger, 1910)
(Guimarães, 1884)
(Boulenger, 1900)
(Poll, 1954)
Norman, 1923
Pellegrin, 1914
Boulenger, 1902
Boulenger, 1911
Skelton & White, 1990
Boulenger, 1905
Boulenger, 1899
Fowler, 1935
Boulenger, 1911
Skelton & White, 1990
Poll, 1967
Pellegrin, 1936
Poll, 1944
Poll, 1952
Ladiges & Voelker, 1961
(Pellegrin, 1928)
Boulenger, 1902
Boulenger, 1906
C
x
x
x
x
x
x
x
x
x
x
Z
O
K
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
Ia
LC
NE
LC
LC
LC
LC
LC
LC
LC
LC
LC
NE
DD
LC
LC
DD
LC
LC
LC
LC
DD
LC
LC
x LC
x LC
x LC
LC
x LC
x LC
x LC
x DD
LC
LC
NE
LC
LC
LC
DD
NE
NE
(continued)
x
236
Species
Procatopodidae
Aplocheilichthys spilauchen
Micropanchax hutereaui
Micropanchax johnstonii
Micropanchax katangae
Micropanchax luluae
Micropanchax macrurus
Micropanchax mediolateralis
Micropanchax myaposae
Micropanchax nigrolateralis
Micropanchax 'pigmy'
Cichlidae
Hemichromis elongatus
Hemichromis angolensis
Pharyngochromis acuticeps
Pseudocrenilabrus philander
Oreochromis andersonii
Oreochromis macrochir
Oreochromis angolensis
Coptodon rendalli
Pelmatolapia cabrae
Oreochromis lepidurus
Oreochromis schwebischi
Tilapia sparrmanii
Tilapia ruweti
Serranochromis altus
Serranochromis angusticeps
Serranochromis longimanus
Serranochromis
macrocephalus
Serranochromis robustus
jallae
Serranochromis thumbergi
Sargochromis greenwoodi
Sargochromis carlottae
Sargochromis giardi
Sargochromis coulteri
Sargochromis codringtonii
Thoracochromis lucullae
Orthochromis machadoi
Sargochromis thysi
Chetia welwitschi
P. H. Skelton
Author & Date
A
(Duméril, 1861)
(Boulenger, 1913)
(Günther, 1894)
(Boulenger, 1912)
(Fowler, 1930)
(Boulenger, 1904)
(Poll, 1967)
(Boulenger, 1908)
(Poll, 1967)
x
x
C
Z
O
x
x
x
x
x
x
x
x
x
x
x
x
x
K
x
x
x
x
x
LC
LC
LC
LC
NE
LC
LC
LC
DD
NE
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
LC
LC
LC
(Boulenger, 1864)
x
x
x
x
LC
(Castelnau, 1861)
(Bell-Cross, 1975)
(Boulenger, 1905)
(Pellegrin, 1903)
(Bell-Cross, 1975)
(Boulenger, 1908)
(Boulenger, 1913)
(Poll, 1967)
(Poll, 1967)
(Boulenger, 1898)
?
x
x
x
x
x
x
x
x
x
x
x
LC
LC
LC
LC
LC
LC
LC
LC
DD
DD
(Guichenot, 1861)
Steindachner, 1865
(Steindachner, 1866)
(Weber, 1897)
(Castelnau, 1861)
(Boulenger, 1912)
(Trewavas, 1973)
(Boulenger, 1897)
(Boulenger, 1899)
(Boulenger, 1899)
(Sauvage, 1884)
Smith, 1840
(Poll & Thys van den
Audenaerde, 1965)
Winemiller & KelsoWinemiller, 1991
(Boulenger, 1907)
(Boulenger, 1911)
(Boulenger, 1899)
x
Ia
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
LC
x
x
x
x
x
x
x
x
LC
NE
LC
LC
VU
VU
LC
LC
LC
EN
LC
LC
LC
x
(continued)
11 The Freshwater Fishes of Angola
Species
Chetia gracilis
Thoracochromis albolabrus
Thoracochromis buysi
Anabantidae
Ctenopoma machadoi
Ctenopoma multispine
Microctenopoma intermedium
Microctenopoma sp.
Mastacembelidae
Mastacembelus ansorgii
Mastacembelus niger
Mastacembelus congicus
Mastacembelus frenatus
Mastacembelus sp.
Eleotridae
Eleotris vittata
Dormitator lebretonis
Gobiidae
Awaous lateristriga
Nematogobius maindroni
Ctenogobius lepturus
Periophthalmus barbarus
Syngnathidae
Enneacampus ansorgii
Enneacampus kaupi
237
Author & Date
(Greenwood, 1984)
(Trewavas & Thys vd
Audenaerde, 1969)
(Penrith, 1970)
A
(Fowler, 1930)
Peters, 1844
(Pellegrin, 1920)
x
C
x
x
Z
x
x
x
Boulenger, 1905
Sauvage, 1879
Boulenger, 1896
Boulenger, 1901
O
x
x
x
x
K
x
Ia
LC
LC
x
LC
x
x
DD
LC
LC
LC
NE
x
x
x
LC
LC
LC
NE
x
x
Duméril, 1861
(Steindachner, 1870)
x
x
LC
NE
(Duméril, 1861)
(Sauvage, 1880)
(Pfaff, 1933)
(Linnaeus, 1766)
x
x
x
NE
NE
NE
LC
x
(Boulenger, 1910)
x
LC
(Bleeker, 1863)
x
LC
TOTALS
104 161 93 103 82
IUCN status (I) as recorded by Darwell et al. (2011) and IUCN (2018). The table is for tentative
indications of distribution and IUCN status
DD data deficient, EN endangered, LC least concern, NE not evaluated, VU vulnerable
a
IUCN Red List Categories Codes
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