Publications by authors named "Jo G Van As"

Chonopeltis Thiele, 1900 presently comprises 14 species, it is endemic to Africa and its species show a high degree of host-specificity towards fish families and in some cases, individual fish species. Chonopeltis meridionalis Fryer, 1964 was originally described from Labeo rosae Steindachner collected in the River Nuanetsi in Rhodesia, now Zimbabwe, Limpopo River System. At the time of description C.

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During surveys of the biodiversity of fish parasites in the Okavango River and Delta, Botswana, specimens of Lamproglena von Nordmann, 1832 were found associated with the African pike Hepsetus odoe (Bloch). This Lamproglena species distinctly differs from all known species based on morphological features, in particular the cephalothorax and the maxilliped; it is described as L. hepseti n.

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A new species of Gyrodactylus von Nordmann, 1832 and the first monogenean reported from Botswana is described from the cichlid Pseudocrenilabrus philander philander, bringing the number of gyrodactylids described from the African Continent to 18. Gyrodactylus thlapi n. sp.

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Argulus multipocula Barnard, 1955 was originally described from a single female found in a littoral sample from the east coast of South Africa. We present a redescription of this species based on light and scanning electron microscope studies of 25 females collected from the southern mullet Liza richardsonii (Smith) on the west coast of South Africa.

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During 2001 and 2002, blood smears from 37 of 120 fishes belonging to 10 species captured in the Okavango Delta region of Botswana, were found to harbour trypanosomes. These trypanosomes displayed differing staining properties, were morphometrically variable, and ranged in total length from 29.5 to 80.

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Five nematode species were recorded from the stomach and rectum of the spotted squeaker Synodontis nigromaculatus Boulenger or the finetooth squeaker S. vanderwaali Skelton & White (Mochokidae, Siluriformes) from the Okavango River, Botswana: Falcaustra similis n. sp.

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Laboratory work was conducted to elucidate the life cycle of the South African gnathiid isopod, Gnathia africana Barnard, 1914. The natural fish hosts of this temporary parasite, the super klipfish Clinus superciliosus (Linnaeus, 1758), were exposed to gnathiid larvae in the laboratory. It was found that G.

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Development stages of a haemogregarine were found in Giemsa-stained heart blood smears of 3 of the 4 horned blennies (Parablennius cornmutus) captured at De Hoop Nature Reserve, South Africa. Gamonts of this haemogregarine conformed to an existing description of Desseria (Haemogregarina) fragilis from P. cornmutus, but intraerythrocytic trophozoites, as well as meronts undergoing division, were reported for the first time for this species.

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Specimens of the physalopterid nematode Proleptus obtusus Dujardin, 1845 collected from the intestine of the puffadder shyshark Haploblepharus edwardsii (Voigt) off De Hoop Nature Reserve, Cape Province, South Africa, made possible the redescription this little-known species. The SEM study of the cephalic end revealed the presence of circumoral denticles and some oral structures (lateral transverse mounds on the inner surface of pseudolabia, dorsolateral and ventrolateral band-like formations or lamellae surrounding the buccal cavity) not previously reported for any species of Proleptus. The shape of the tip of the right spicule is considered to be the only reliable feature for differentiating P.

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During parasitological surveys in the Okavango Delta and Panhandle in Botswana, two species of climbing perches belonging to the family Anabantidae were investigated for ectoparasites. The fishes were the blackspot climbing perch, Microctenopoma intermedium (Pellegrin) and the manyspined climbing perch, Ctenopoma multispine Peters. Five trichodinid species were found from the skin, fins and gills of these anabantids.

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Caligus mortis Kensley, 1970 was originally described from females collected from intertidal pools along the coast of Namibia. During surveys at Jeffreys Bay and De Hoop Nature Reserve in South Africa, both females and males of C. mortis were collected from intertidal pool fish hosts.

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A redescription of the female of the temporary fish parasite, Gnathia africana Barnard, 1914 is provided from specimens reared from final-stage G. africana praniza larvae collected from their intertidal fish hosts along the south coast of southern Africa. It differs from other known gnathiid females in the shape of the frontal border and the number and basic form of pylopod articles.

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