Four new species of Cichlidogyrus Paperna, 1960 (Monogenea, Ancyrocephalidae), all gill parasites from African mouthbreeder tilapias of the genera Sarotherodon and Oreochromis (Pisces, Cichlidae), with a redescription of C-thurstonae Ergens, 1981

A study of Oreochromis niloticus ( Linnaeus), O. aureus ( Steindachner), Sarotherodon caudomarginatus ( Boulenger), S. galilaeus ( Linnaeus) and S. galilaeus sanagaensis ( Thys van den Audenaerde) ( Teleostei, Cichlidae) from different locations in Africa ( Burkina Faso, Cameroon, Guinea, Niger and Senegal) revealed the presence of 11 species of monogenean gill parasites. Four, belonging to Cichlidogyrus Paperna, 1960 and considered as new species, are described: C. rognoni n. sp., C. douellouae n. sp., C. giostrai n. sp. and C. njinei n. sp. They are distinguished by the shape and/ or size of the sclerotised parts of the haptoral and copulatory complexes. C. thurstonae Ergens, 1981 from O. niloticus is redescribed.