Nelabrichthys, a new genus of labrid fish (Perciformes: Labridae) from the southern Indian and Atlantic Oceans
- Authors: Russell, Barry C , J.L.B. Smith Institute of Ichthyology
- Date: 1983-01
- Subjects: Wrasses , Fishes -- Classification
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/69980 , vital:29604 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
- Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 27 , A new monotypic genus of labrid fish, Nelabrichthys, is recognized for Labrus ornatus Carmichael, described from Tristan da Cunha in the South Atlantic. Labrichthys lantzii Sauvage and L. isleanus Sauvage from Saint-Paul Island in the southern Indian Ocean, and Platyglossus robinsoni Gilchrist and Thompson, erroneously thought to be from the Natal coast of South Africa, are junior syonyms of N. ornatus.
- Full Text:
- Date Issued: 1983-01
Pteropsaron heemstrai and Osopsaron natalensis (Perciformes: Percophidae), new fish species from South Africa, with comments on Squamicreedia obtusa from Australia and on the classification of the subfamily Hemerocoetinae
- Authors: Nelson, Joseph S , J.L.B. Smith Institute of Ichthyology
- Date: 1982-11
- Subjects: Fishes -- South Africa , Fishes -- Australia , Perciformes , Percophidae
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/69940 , vital:29597 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
- Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 25 , Two new species of percophid fishes are described from off Natal, South Africa, Pteropsaron heemstrai from two specimens dredged at 143 m and Osopsaron natalensis from three specimens dredged at 100 m. This is the first record of a member of the subfamily Hemerocoetinae from the western Indian Ocean. The two new species belong to the lineage of closely related genera Acanthaphrites Gunther, Pteropsaron Jordan and Snyder, Osopsaron Jordan and Starks, Spinapsaron Okamura and Kishida, and Branchiopsaron McKay. A specimen of Squamicreedia obtusa Rendahl, previously known only from the damaged holotype, is described from Western Australia. It is postulated that the genera Squamicreedia Rendahl, Enigmapercis Whitley (whose range is extended to Western Australia), and Matsubaraea Taki form a closely related group in Hemerocoetinae.
- Full Text:
- Date Issued: 1982-11
Problems of species definition in Lake Malawi cichlid fishes (Pisces: Cichlidae)
- Authors: Lewis, Digby S C , J.L.B. Smith Institute of Ichthyology
- Date: 1982-09
- Subjects: Cichlids -- Nyasa, Lake , Fishes
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/69918 , vital:29595 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
- Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 23 , The evolution of the cichlid species flock in Lake Malawi has taken place very rapidly and resulted in the proliferation of a large number of species many of which are similar to one another. This has given rise to a situation in which traditional methods of distinguishing species based on preserved specimens are often of limited value. There are many instances of different species having almost identical morphologies, of single populations of one species showing considerable morphological variation and of marked geographical intraspecific variation. Polymorphism is considered not to be as widespread as previously thought, and pronounced random intraspecific colour variation within a population is discounted. Sympatric sibling species may be distinguished by observing behavioural and habitat differences in the field, but no means has been devised for ascertaining whether morphologically and behaviourally similar allopatric forms are specifically distinct. Lack of access to fresh specimens and lack of information on distribution and habitat have resulted in numerous errors appearing in taxonomic works on Lake Malawi cichlids. Great care is needed when attempting scientific descriptions of cichlid species from the African Great Lakes, and it is suggested that such work be left to specialists with knowledge of living and fresh fish in these lakes.
- Full Text:
- Date Issued: 1982-09
The distribution and identification of mormyrid fishes in Malawi, with notes on the synonymy of Marcusenius nyasensis and M. livingstonii (Mormyriformes: Mormyridae)
- Authors: Tweddle, D S C , Willoughby, N G , J.L.B. Smith Institute of Ichthyology
- Date: 1982-09
- Subjects: Fishes -- Identification , Fishes -- Malawi
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/69929 , vital:29596 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
- Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 24 , Electrofishing surveys throughout Malawi have increased the number of mormyrid species known to occur in the country, expanded known ranges of the species and cast doubts on some earlier records. The distribution of each of the eight recorded species is given, and a key is provided for the identification of the species. The available evidence suggests that Gnathonemus nyasensis Worthington, 1933 is a junior synonym of Marcusenius livingstonii (Boulenger, 1898) a species described from the Ruvuma River of Tanzania. Geological evidence supports fish distribution evidence that indicates links between Lake Malawi and East Coast Rivers. Some affinities are also noted between Lake Malawi and Upper Zambezi/Zaire faunas.
- Full Text:
- Date Issued: 1982-09
Plotonus nkunga, a new species of catfish from South Africa, with a redescription of Plotosus limbatus Valenciennes and key to the species of Plotosus (Siluriformes: Plotosidae)
- Authors: Gomon, Janet R , Taylor, William Ralph , J.L.B. Smith Institute of Ichthyology
- Date: 1982-08
- Subjects: Catfishes
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/69871 , vital:29590 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
- Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 22 , Plotosus nkunga sp. n., from the east coast of South Africa, possibly ranging as far north as Zanzibar, is most similar to Plotosus limbatus Valenciennes, from the coasts of India, Sri Lanka, Kenya and Aldabra. Plotosus nkunga differs most notably in having fewer total gill rakers on the anterior faces of the first two arches, 16 to 21 versus 20 to 25 first arch, 16 to 24 versus 23 to 27 second arch; in having modally one more precaudal vertebra and slight modal differences in number of ribs and branchiostegal rays; in the shapes of the mesethmoid and the parapophyses of the fourth and fifth centra of the anterior complex vertebra; in the length of the maxilla; and in certain body proportions. Descriptions, annotated synonymies and illustrations are given for both species. A key to the five known species of Plotosus is presented.
- Full Text:
- Date Issued: 1982-08