Of three intertidal fish species collected on the east coast of South Africa, 67% (127/190) had haemogregarine infections. Horned rockskippers, Antennablennius bifilum Günther, 1861, demonstrated 77% parasite prevalence, maned blennies, Scartella emarginata Günther, 1861, 53% prevalence, and a single specimen of the hotlips triplefin, Helcogramma obtusirostre Klunzinger, 1871, was also parasitized. Less than 1% of A. bifilum and S. emarginata erythrocytes were infected, but ~2% of those of H. obtusirostre. Haemogregarines in A. bifilum and S. emarginata were morphologically similar to H. bigemina Laveran & Mesnil, 1901, but uncharacteristic clusters of four merozoites were observed in S. emarginata and paired gamonts were smaller overall than those of the type species, although close in size to H. bigemina reported elsewhere. Intraerythrocytic gamonts in H. obtusirostre, occurred mainly in fours, a characteristic of the European species originally named H. quadrigemina Brumpt & Lebailly, 1904. Additionally however, this South African species infrequently demonstrated eight intraerythrocytic gamonts and host cells commonly had spiny perimeters and were de-haemoglobulinized. Owing to the differences observed, this species is described as new to science and named Haemogregarina kunegemina sp. nov. Possible haemogregarine developmental stages were found in first and second stage pranizae of the gnathiid isopod, Gnathia pilosus Hadfield, Smit & Avenant-Oldewage, 2008, that had fed on the three fish hosts. These are the first reports of haemogregarines from teleosts of the subtropical east coast of South Africa.