INVESTIGATIONS INTO THE TRANSMISSION OF HAEMOGREGARINA-BIGEMINA LAVERAN AND MESNIL, 1901 (APICOMPLEXA, ADELEORINA) BETWEEN INTERTIDAL FISHES IN PORTUGAL

During two summers in Portugal, intertidal fishes were captured with a naesthetic at four sites along the Portuguese Atlantic West Coast. The y were examined for the blood parasite Haemogregarina bigemina, for ot her haematozoa, and for haematophagous ecto-parasites. Haemogregarina bigemina was found only in blennies, Lipophrys pholis (L.) and Corypho blennius galerita (L.), and infections in these fish were similar. No other haematozoa were detected. Ectoparasites found attached to blenni es included haematophagous praniza larvae of the isopod Gnathia maxill aris and a single leech. Gametocytes like those of fish haemogregarine s were found in the anterior hindgut of 25% of pranizae and one contai ned gametocytes and stages resembling early oocysts. The leech showed none of these stages. It is concluded that gnathiid pranizae should be considered as possible vectors of H. bigemina in Portugal.