A contribution to the taxonomy of the marine fish genus Argyrosomus (Perciformes: Sciaenidae), with descriptions of two new species from southern Africa
- Griffiths, Marc H, Heemstra, Phillip C
- Authors: Griffiths, Marc H , Heemstra, Phillip C
- Date: 1995
- Language: English
- Type: Text
- Identifier: vital:15027 , http://hdl.handle.net/10962/d1019891 , ISSN 0073-4381 , Ichthyological Bulletin J.L.B. Smith Institute of Ichthyology; No. 65
- Description: Study of the biology, anatomy and taxonomy of the sciaenid fishes of the genus Argyrosomus from South Africa and Namibia revealed that three species were confused under the name ‘Argyrosomus hololepidotus (Lacepede, 1801)”. Comparison of morphometric and meristic data, otoliths, swim-bladders, drumming muscles, and other morphological features, of specimens from southern Africa, Madagascar, the Mediterranean Sea, the eastern Atlantic Ocean, Japan and Australia, established that the “A. hololepidotus” of recent authors is a complex of four species: A. japonicus (Temminck & Schlegel, 1843), which occurs off southern Africa, Japan and Australia; A. inodorus sp. nov., which is known from Namibia to the Kei River (32°40’S) on the east coast of South Africa; A. coronus sp. nov., which is known from central and northern Namibia and Angola, and A. hololepidotus, which appears to be endemic to Madagascar. These four species are compared with A. regius (Asso, 1801) of the Mediterranean and eastern Atlantic, A. thorpei Smith, 1977 from South Africa, Mozambique and the west coast of Madagascar, and A. beccus Sasaki, 1994 known only from Durban harbour. To promote stability in the nomenclature and to resolve the confusion in the taxonomy of Argyrosomus species, neotypes are selected for A. hololepidotus and A. japonicus. The biology, distributions and fisheries of six species are reviewed. Distribution patterns for the southern African species and a key to the seven species known from Africa and Madagascar (A. regius, A. japonicus, A. inodorus, A. coronus, A. thorpei, A. beccus, and A. hololepidotus) are provided. The composition and distinction of the genus Argyrosomus are briefly discussed. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1995
- Authors: Griffiths, Marc H , Heemstra, Phillip C
- Date: 1995
- Language: English
- Type: Text
- Identifier: vital:15027 , http://hdl.handle.net/10962/d1019891 , ISSN 0073-4381 , Ichthyological Bulletin J.L.B. Smith Institute of Ichthyology; No. 65
- Description: Study of the biology, anatomy and taxonomy of the sciaenid fishes of the genus Argyrosomus from South Africa and Namibia revealed that three species were confused under the name ‘Argyrosomus hololepidotus (Lacepede, 1801)”. Comparison of morphometric and meristic data, otoliths, swim-bladders, drumming muscles, and other morphological features, of specimens from southern Africa, Madagascar, the Mediterranean Sea, the eastern Atlantic Ocean, Japan and Australia, established that the “A. hololepidotus” of recent authors is a complex of four species: A. japonicus (Temminck & Schlegel, 1843), which occurs off southern Africa, Japan and Australia; A. inodorus sp. nov., which is known from Namibia to the Kei River (32°40’S) on the east coast of South Africa; A. coronus sp. nov., which is known from central and northern Namibia and Angola, and A. hololepidotus, which appears to be endemic to Madagascar. These four species are compared with A. regius (Asso, 1801) of the Mediterranean and eastern Atlantic, A. thorpei Smith, 1977 from South Africa, Mozambique and the west coast of Madagascar, and A. beccus Sasaki, 1994 known only from Durban harbour. To promote stability in the nomenclature and to resolve the confusion in the taxonomy of Argyrosomus species, neotypes are selected for A. hololepidotus and A. japonicus. The biology, distributions and fisheries of six species are reviewed. Distribution patterns for the southern African species and a key to the seven species known from Africa and Madagascar (A. regius, A. japonicus, A. inodorus, A. coronus, A. thorpei, A. beccus, and A. hololepidotus) are provided. The composition and distinction of the genus Argyrosomus are briefly discussed. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1995
A review of the species of the genus Neobythites (Pisces: Ophidiidae) from the Western Indian Ocean, with a description of seven new species
- Authors: Nielsen, Jørgen G
- Date: 1995
- Language: English
- Type: Text
- Identifier: vital:15024 , http://hdl.handle.net/10962/d1019887 , ISBN 0-86810-281-4 , Ichthyological Bulletin J.L.B. Smith Institute of Ichthyology; No. 62
- Description: Species of the ophidiid genus Neobythites from the western Indian Ocean are revised based on 225 specimens. The majority of specimens came from the 17th cruise (1988-89) of the Soviet R/V VITYAZ. Twelve species are recognized: N. analis Barnard, 1927 (southern Africa; lectotype designed), N. crosnieri sp.n. (Madagascar), N. kenyaensis sp.n, (east coast of Africa), N. malhaensis sp.n. (Saya de Malha Bank), N. meteori sp.n. (Socotra Id.), N. multistriatus Nielsen and Quero, 1991 (Reunion and Rodrigues Islands), N. natalensis sp.n. (South Africa and Madagascar), N. somaliaensis sp.n. (Somalia), N. steatiticus Alcock, 1893 (northern Indian Ocean), N. stefanovi Nielsen and Uiblein, 1993 (Red Sea to Gulf of Oman), N. trifilis Kotthaus, 1979 (Socotra Id.), N. vityazi sp.n. (Madagascar). All 12 species are illustrated, and a key is included. This paper is the first part of a revision of the genus Neobythites. A second and third part will treat the species from the East Indian/Pacific Oceans and the Atlantic Ocean. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1995
- Authors: Nielsen, Jørgen G
- Date: 1995
- Language: English
- Type: Text
- Identifier: vital:15024 , http://hdl.handle.net/10962/d1019887 , ISBN 0-86810-281-4 , Ichthyological Bulletin J.L.B. Smith Institute of Ichthyology; No. 62
- Description: Species of the ophidiid genus Neobythites from the western Indian Ocean are revised based on 225 specimens. The majority of specimens came from the 17th cruise (1988-89) of the Soviet R/V VITYAZ. Twelve species are recognized: N. analis Barnard, 1927 (southern Africa; lectotype designed), N. crosnieri sp.n. (Madagascar), N. kenyaensis sp.n, (east coast of Africa), N. malhaensis sp.n. (Saya de Malha Bank), N. meteori sp.n. (Socotra Id.), N. multistriatus Nielsen and Quero, 1991 (Reunion and Rodrigues Islands), N. natalensis sp.n. (South Africa and Madagascar), N. somaliaensis sp.n. (Somalia), N. steatiticus Alcock, 1893 (northern Indian Ocean), N. stefanovi Nielsen and Uiblein, 1993 (Red Sea to Gulf of Oman), N. trifilis Kotthaus, 1979 (Socotra Id.), N. vityazi sp.n. (Madagascar). All 12 species are illustrated, and a key is included. This paper is the first part of a revision of the genus Neobythites. A second and third part will treat the species from the East Indian/Pacific Oceans and the Atlantic Ocean. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1995
Fish community structure in three temporarily open/closed estuaries on the Natal coast
- Harrison, Trevor D, Whitfield, Alan K
- Authors: Harrison, Trevor D , Whitfield, Alan K
- Date: 1995
- Language: English
- Type: Text
- Identifier: vital:15026 , http://hdl.handle.net/10962/d1019890 , ISSN 0073-4381 , Ichthyological Bulletin J.L.B. Smith Institute of Ichthyology; No. 64
- Description: The fishes of three small Natal estuaries, the Mhlanga, Damba and Zotsha were sampled over a period of two years. A total of 68 fish taxa representing 24 families, 39 genera and 55 species were captured during this study. Forty seven fish taxa were recorded in the Mhlanga estuary of which Gilchristella aestuaria, Oreochromis mossambicus, Valamugil cunnesius, Valamugil sp. and juvenile mugilids numerically dominated. In terms of biomass, O. mossambicus, V. cunnesius, Liza alata, Myxus capensis and Mugil cephalus dominated the ichthyofauna of the Mhlanga system. In the Damba estuary, 24 fish taxa were recorded, the most abundant being Glossogobius callidus,M. capensis and 0. mossambicus. M. capensis, M. cephalus, O. mossambicus and G. callidus dominated the fish biomass captured in the Damba system. A total of 56 fish taxa were recorded in the Zotsha estuary during this study, with the ichthyofauna numerically dominated by juvenile mugilids, G. aestuaria, O. mossambicus, Rhabdosargus holubi, Terapon jarbua, Ambassis productus and G. callidus. The species which dominated the fish biomass in the Zotsha system were 0. mossambicus L. alata, Valamugil robustus, V. buchanani, M. capensis, M. cephalus and V. cunnesius. Classifying the species according to whether they were resident estuarine, freshwater, estuarine-dependent marine or marine species revealed that the first three groups were all well represented in the systems. Oreochromis mossambicus was the dominant freshwater species in all three estuaries. Gilchristella aestuaria and Glossogobius callidus were the principal estuarine species in the Mhlanga and the Damba respectively, with G. aestuaria, A. productus and G. callidus being the dominant estuarine species captured in the Zotsha. The principal estuarine-dependent marine fishes captured in the Mhlanga were V. cunnesius, Valamugil sp., juvenile mugilids, M. capensis, M. cephalus and L. alata. In the Damba, M. capensis and M. cephalus were the dominant estuarine-dependent marine species and in the Zotsha juvenile mugilids, R. holubi, T. jarbua, M. capensis, V. cunnesius, V. robustus, M. cephalus, L. alata and V. buchanani were the principal estuarine-dependent marine species. The results of this study indicate that the estuaries are dominated at different periods by different assemblages of fishes. This is linked to the spawning and migration patterns of the various species as well as the hydrological regime of each estuary. During the winter these systems are normally closed with relatively deep waters and high food resource and habitat availability. Freshwater and estuarine species mainly inhabit the upper reaches of the systems while estuarine-dependent marine species, which dominate the fish community, mainly occupy the middle and lower reaches. When these estuaries open with the onset of the spring/summer rains, adult and sub-adult estuarine-dependent marine species emigrate to the marine environment and juveniles begin recruiting into the systems. Spring is also the peak breeding period of resident estuarine and freshwater species, resulting in an increase in the contribution of these fishes to the overall ichthyofauna during this period. When closed estuaries open the water level falls and this results in the fishes concentrating in the lower reaches of the system where moderate water depths are present, thus further contributing to an increase in the proportion of freshwater and estuarine species in this region. The breaching of closed estuaries also results in a reduction in food resources and habitat availability. Competition and possible increased vulnerability to avian predation (due to the shallow nature of the systems), may contribute to a decrease in the proportion of estuarine and freshwater species in summer. The prolonged recruitment of Of-juveniles of estuarine-dependent marine species results in an increase in the proportion of these fishes present in the estuaries during summer. In autumn, the systems normally close, water levels rise and available food resources and habitat increase. This allows the redistribution of freshwater and estuarine species upstream, leaving estuarine-dependent marine species to dominate the middle and lower reaches. Although temporarily open/closed estuaries along the Natal coast may not be as diverse as permanently open estuaries in terms of their ichthyofauna, their importance must not be underestimated, since by providing a series of sheltered habitats along the coast they may contribute significantly to the viability of estuarine-dependent marine fish stocks. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1995
- Authors: Harrison, Trevor D , Whitfield, Alan K
- Date: 1995
- Language: English
- Type: Text
- Identifier: vital:15026 , http://hdl.handle.net/10962/d1019890 , ISSN 0073-4381 , Ichthyological Bulletin J.L.B. Smith Institute of Ichthyology; No. 64
- Description: The fishes of three small Natal estuaries, the Mhlanga, Damba and Zotsha were sampled over a period of two years. A total of 68 fish taxa representing 24 families, 39 genera and 55 species were captured during this study. Forty seven fish taxa were recorded in the Mhlanga estuary of which Gilchristella aestuaria, Oreochromis mossambicus, Valamugil cunnesius, Valamugil sp. and juvenile mugilids numerically dominated. In terms of biomass, O. mossambicus, V. cunnesius, Liza alata, Myxus capensis and Mugil cephalus dominated the ichthyofauna of the Mhlanga system. In the Damba estuary, 24 fish taxa were recorded, the most abundant being Glossogobius callidus,M. capensis and 0. mossambicus. M. capensis, M. cephalus, O. mossambicus and G. callidus dominated the fish biomass captured in the Damba system. A total of 56 fish taxa were recorded in the Zotsha estuary during this study, with the ichthyofauna numerically dominated by juvenile mugilids, G. aestuaria, O. mossambicus, Rhabdosargus holubi, Terapon jarbua, Ambassis productus and G. callidus. The species which dominated the fish biomass in the Zotsha system were 0. mossambicus L. alata, Valamugil robustus, V. buchanani, M. capensis, M. cephalus and V. cunnesius. Classifying the species according to whether they were resident estuarine, freshwater, estuarine-dependent marine or marine species revealed that the first three groups were all well represented in the systems. Oreochromis mossambicus was the dominant freshwater species in all three estuaries. Gilchristella aestuaria and Glossogobius callidus were the principal estuarine species in the Mhlanga and the Damba respectively, with G. aestuaria, A. productus and G. callidus being the dominant estuarine species captured in the Zotsha. The principal estuarine-dependent marine fishes captured in the Mhlanga were V. cunnesius, Valamugil sp., juvenile mugilids, M. capensis, M. cephalus and L. alata. In the Damba, M. capensis and M. cephalus were the dominant estuarine-dependent marine species and in the Zotsha juvenile mugilids, R. holubi, T. jarbua, M. capensis, V. cunnesius, V. robustus, M. cephalus, L. alata and V. buchanani were the principal estuarine-dependent marine species. The results of this study indicate that the estuaries are dominated at different periods by different assemblages of fishes. This is linked to the spawning and migration patterns of the various species as well as the hydrological regime of each estuary. During the winter these systems are normally closed with relatively deep waters and high food resource and habitat availability. Freshwater and estuarine species mainly inhabit the upper reaches of the systems while estuarine-dependent marine species, which dominate the fish community, mainly occupy the middle and lower reaches. When these estuaries open with the onset of the spring/summer rains, adult and sub-adult estuarine-dependent marine species emigrate to the marine environment and juveniles begin recruiting into the systems. Spring is also the peak breeding period of resident estuarine and freshwater species, resulting in an increase in the contribution of these fishes to the overall ichthyofauna during this period. When closed estuaries open the water level falls and this results in the fishes concentrating in the lower reaches of the system where moderate water depths are present, thus further contributing to an increase in the proportion of freshwater and estuarine species in this region. The breaching of closed estuaries also results in a reduction in food resources and habitat availability. Competition and possible increased vulnerability to avian predation (due to the shallow nature of the systems), may contribute to a decrease in the proportion of estuarine and freshwater species in summer. The prolonged recruitment of Of-juveniles of estuarine-dependent marine species results in an increase in the proportion of these fishes present in the estuaries during summer. In autumn, the systems normally close, water levels rise and available food resources and habitat increase. This allows the redistribution of freshwater and estuarine species upstream, leaving estuarine-dependent marine species to dominate the middle and lower reaches. Although temporarily open/closed estuaries along the Natal coast may not be as diverse as permanently open estuaries in terms of their ichthyofauna, their importance must not be underestimated, since by providing a series of sheltered habitats along the coast they may contribute significantly to the viability of estuarine-dependent marine fish stocks. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1995
Fishes of the Tristan da Cunha Group and Gough Island, South Atlantic Ocean
- Andrew, T G, Hecht, Thomas, Heemstra, Phillip C, Lutjeharms, J R E
- Authors: Andrew, T G , Hecht, Thomas , Heemstra, Phillip C , Lutjeharms, J R E
- Date: 1995
- Language: English
- Type: Text
- Identifier: vital:15025 , http://hdl.handle.net/10962/d1019889 , ISSN 0073-4381 , Ichthyological Bulletin J.L.B. Smith Institute of Ichthyology; No. 63
- Description: Recent collections of fishes from the South Atlantic islands of the Tristan da Cunha Group (Tristan, Inaccessible and Nightingale) and Gough Island have produced 25 new records. Fifty one species are known to occur in the near-shore waters of the islands (46 of these are documented by specimens and another 5 species are probable). A diagnosis, synonymy and in most cases, an illustration, are provided for each species. For certain species, brief notes on biology, relative abundance and seasonal distribution are included. The neritic ichthyofauna of the Subtropical Convergence (STC) region is characterized, and the importance of this frontal zone as a barrier to dispersal of species in the Southern Ocean is evaluated. Analysis of the zoogeographic affinities of the Tristan/Gough fish fauna resulted in a redefinition of the West Wind Drift Islands Province (WWDI), comprising the Tristan Group and Gough in the South Atlantic and St. Paul and Amsterdam Islands in the southern Indian Ocean. Verna Seamount (west of Cape Town) and Walters Shoal (south of Madagascar) are excluded from the WWDI Province, as the affinities of their poorly-known fish faunas appear to be more with South Africa and the tropical Indian Ocean respectively. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1995
- Authors: Andrew, T G , Hecht, Thomas , Heemstra, Phillip C , Lutjeharms, J R E
- Date: 1995
- Language: English
- Type: Text
- Identifier: vital:15025 , http://hdl.handle.net/10962/d1019889 , ISSN 0073-4381 , Ichthyological Bulletin J.L.B. Smith Institute of Ichthyology; No. 63
- Description: Recent collections of fishes from the South Atlantic islands of the Tristan da Cunha Group (Tristan, Inaccessible and Nightingale) and Gough Island have produced 25 new records. Fifty one species are known to occur in the near-shore waters of the islands (46 of these are documented by specimens and another 5 species are probable). A diagnosis, synonymy and in most cases, an illustration, are provided for each species. For certain species, brief notes on biology, relative abundance and seasonal distribution are included. The neritic ichthyofauna of the Subtropical Convergence (STC) region is characterized, and the importance of this frontal zone as a barrier to dispersal of species in the Southern Ocean is evaluated. Analysis of the zoogeographic affinities of the Tristan/Gough fish fauna resulted in a redefinition of the West Wind Drift Islands Province (WWDI), comprising the Tristan Group and Gough in the South Atlantic and St. Paul and Amsterdam Islands in the southern Indian Ocean. Verna Seamount (west of Cape Town) and Walters Shoal (south of Madagascar) are excluded from the WWDI Province, as the affinities of their poorly-known fish faunas appear to be more with South Africa and the tropical Indian Ocean respectively. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1995
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