- Title
- The fish Elops machnata in South Africa
- Title
- Special Publication (J.L.B. Smith Institute of Ichthyology) no.11
- Creator
- Fraser, Thomas H
- Creator
- Rhodes University. J.L.B. Smith Institute of Ichthyology
- Subject
- Elopidae -- South Africa
- Subject
- Elops -- Indian Ocean
- Subject
- Fishes -- South Africa
- Date Issued
- 1973-08
- Date
- 1973-08
- Type
- text
- Type
- book
- Identifier
- http://hdl.handle.net/10962/69652
- Identifier
- vital:29563
- Identifier
- 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. 11
- Description
- Introduction: The status of the species of Elops present in the Indian Ocean along the southern part of Africa has been uncertain in recent times. Two names have been applied - Elops saurus Linnaeus, 1766 and Elops machnata (Forsskål, 1775) by numerous workers up to the present despite three revisions of Elops concluding that only one species, E. machnata, occurs in the western Indian Ocean (Regan, 1909; Bertin, 1944; Whitehead, 1962). These workers also demonstrated that Elops saurus is fotmd only in the western Atlantic Ocean and can be separated 100% of the time from E. machnata by vertebral counts (73-82 in E. saurus and 60-66 in E. machnata). Why, then, have workers persisted in using both names but not exclusively one or the other? There appear to be two reasons: 1. Some workers regard Elops to consist of one world-wide tropical species (in which case E. saurus is the oldest valid name). 2. The inadequate material upon which Regan, Bertin and Whitehead based their conclusions about the species of Elops. The first idea does not appear to be tenable with the evidence presented in the three species revisions and I regard it as erroneous. The second reason is real. We lack the basic information on geographic variation, if any, for the Indian Ocean population. Regan (1909) examined two specimens, Bertin (1944) an unknown number and Whitehead (1962) seven specimens. Whitehead (1965:231) indicates some doubt about the South African population and its status relative to the West African species E. senegalensis Regan, 1909. Furthermore, both Whitehead (1965) and Losse (1968) suggest that E. machnata and E. hawaiensis Regan, 1909 possibly may be subspecies of the same species, but indicate present data to be inadequate. This paper documents meristic and morphometric variation of 39 Elops mostly taken in South African estuaries as a first step toward understanding variation of the southern-most population in the Indian Ocean. South of Durban, South Africa, Elops machnata frequents the coastal waters only during the warmer months and is known to reach Mossel Bay. No species of Elops has been reported along the colder south western coast of southern Africa. The size range examined is large, 30 mm-900 mm SL (or to 6,9 kg), but does not include the maximum recorded size in South Africa of 13,7 kg. Losse's (1968) data for central East Africa are of nearly comparable size range and provide a useful comparison.
- Format
- 8 pages
- Format
- Publisher
- Rhodes University. J.L.B. Smith Institute of Ichthyology
- Language
- English
- Relation
- Special Publication (J.L.B. Smith Institute of Ichthyology)
- Relation
- Fraser, T. H. (1973) The fish Elops machnata in South Africa. Grahamstown, Rhodes University, J.L.B. Smith Institute of Ichthyology, Special publication, no. 11
- Relation
- Special Publication (J.L.B. Smith Institute of Ichthyology) volume number 11 1 8 Augustus 1973 0075-2088
- Rights
- Rhodes University, Grahamstown, South Africa
- Rights
- Use of this resource is governed by the terms and conditions of the Creative Commons Attribution 4.0 International (CC BY 4.0) License (https://creativecommons.org/licenses/by/4.0/)
- Hits: 1383
- Visitors: 1380
- Downloads: 56
Thumbnail | File | Description | Size | Format | |||
---|---|---|---|---|---|---|---|
View Details Download | SOURCE1 | Adobe Acrobat PDF | 193 KB | Adobe Acrobat PDF | View Details Download |