Spatial Distribution of Myxobolus Pethericii and Henneguya Pethericii on the Gills of an African Anabantid Ctenopoma Petherici from the Sange River, Cameroon

摘要

The spatial distribution of Myxobolus pethericii Fomena, Lekeufack folefack and Tang II, 2007 and Henneguyapethericii Fomena, Lekeufack folefack and Bouix, 2008 gills parasites of Ctenopoma petherici Gunther, 1864 wasinvestigated. The gill apparatus of each host individual was divided into arbitrary regions and the number of cysts ofeach parasites species in each gill region was determined. Results were analysed at parasite species andxenocommunity levels. Site specificity was determined by application of Chi-square test to the data. At the sametime, mean cyst loads were compared between different gill regions. The mean cyst load of the xenocommunity washigher on arches II and III than on arch IV. M. pethericii encysted more on outer hemibranch of arch IV. The medialsegment of the gill was more colonized by M. pethericii and the combination made of M. pethericii+H. pethericii. Thegreater mean cyst load of M. pethericii was observed on medial segment. The specific preferences of a gill regionmight be affected by the interaction of factors such as the possible heterogeneity of the gill system, possibledifferences in the hydrostatic pressure of the branchial pump and the water current over different parts of the gillsurface.