Systematic studies of the African species of the genus Garra (Pisces: Cyprinidae).
Item
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Title
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Systematic studies of the African species of the genus Garra (Pisces: Cyprinidae).
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Identifier
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AAI9959180
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identifier
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9959180
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Creator
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Getahun, Abebe.
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Contributor
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Adviser: Melanie Stiassny
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Date
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2000
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Language
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English
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Publisher
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City University of New York.
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Subject
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Biology, Zoology
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Abstract
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Morphological, morphometric and meristic characters have been used to resolve the taxonomic confusion that exists among the African species of the genus Garra. Five species (G. dembecha, G. duobarbis, G. geba, G. microstoma and G. tana) are described for the first time. Three species (G. aethiopica, G. blanfordii and G. hindii) are resurrected and two species, G. trewavasae and G. tibanica, are synonymized with G. ornata and (G. quadrimaculata) respectively. A total of 29 nominal species have so far been described from the Continent and 17 species are, herein, recognized valid. A neotype is designated for one species, G. dembeensis, in which the type specimen is lost and the original description and the illustration are found to be inadequate. 6 lectotypes were designated for species previously known from syntypes ( G. aethiopica, G. blanfordii, G. hindii G. ignestii, G. lancrenonensis and G. makiensis).;The monophyly of the sub-family, in which Garra is placed---Labeinae, and the interrelationships of the genera within are evaluated. The monophyly of the sub-family is corroborated with four synapomorphies. Garra is closely related to the disc bearing genera Discogobio, Discocheilus and Semilabeo.;Three synapomorphies (the presence of two or more anterior unbranched fin rays, an elongated cleithrum and a wide and short supraethmoid) corroborate the monophyly of the genus Garra. But, there is no evidence that suggests the monophyly of the African Garra.;The interspecific relationship of Garra could not be completely resolved. However, one clade and two sub-clades could be recognized. The clades consist of both African and Asian species.;Species of the genus are found in freshwaters of Africa from Ethiopia in the east to Guinea in the west and Egypt in the north (following the Nile river) to Tanzania in the southeast. Its range is also extended to the Zaire basin and Angolan freshwaters in the southwest. Species richness tends to decrease from east to west. In Ethiopia, where the species richness is highest, 75% of the species are from two northern drainage basins (The Abbay and Tekezze basins). One species (G. quadrimaculata) is shared by the Afro-Arabian countries, being found in three African countries (Eritrea, Ethiopia, and Somalia) and in the Arabian Peninsula (e.g. Yemen, Saudi Arabia). An early Paleocene Gondwanic origin of Garra is suggested with a Vicariance-Dispersal-Vicariance model.
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Type
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dissertation
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Source
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PQT Legacy CUNY.xlsx
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degree
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Ph.D.
