New host records for Haemogregarina bigemina from the coast of southern Africa

One hundred and fifty intertidal fishes were captured at Jeffreys Bay in Ju ly 1996 and February 1997, and at De Hoop Nature Reserve in April 1997, Sou th Africa. Caffrogobius caffer, Chorisochismus dentex, Clinus superciliosus , and Clinus cottoides were all parasitised by haematophagous larvae of the isopod, Gnathia africana, and between 22 and 81% of fishes were infested w ith 1 to 76 larvae each. Of those fishes examined for blood parasites, 35/4 6 (76.1%) had an intraerythrocytic haemogregarine identified as Haemogregar ina (sensu lato) bigemina, but only Clinus superciliosus and Clinus cottoid es were infected. Gamonts of the haemogregarine, some undergoing syzygy, we re also present in 50% of stained batches of the anterior hindgut contents of G. africana larvae which had fed on Clinus superciliosus, but were absen t from larvae taken from Clinus cottoides and Chorisochismus dentex. This s tudy provides new host records for H. bigemina and further evidence that gn athiid isopods play a role in the transmission of the haemogregarine.