Haemogregarines and other blood infections from deep demersal fish of the Porcupine Seabight, north-east Atlantic

Giemsa-stained blood smears were examined from 70 deep demersal fish of 27 species in 20 genera, trawled from depths of 747-4143 m in the region of th e Porcupine Seabight, north-east Atlantic. Infections were found in four sp ecies of teleosts in three families: 1/3 Alepocephalus rostratus and 1/3 Na rcetes stomias (Alepocephalidae); 2/3 Antimora rostrata (Moridae); and 1/1 Cataetyx laticeps (Bythitidae). Blood films from C. laticeps and Antimora r ostrata were well preserved but those from the other two species were less satisfactory. The blood parasites included two types of haemogregarines, Ha emohormidium-like and viral erythrocytic necrosis (VEN)-like infections. Ha emogregarina (sensu bate) johnstoni sp. nov. was described from C. laticeps captured at 1541 m. This haemogregarine was unusual in apparently having d imorphic gamonts, some with prominent caps. A second, but monomorphic, haem ogregarine found in Alepocephalus rostratus captured from 985 m, was named as Desseria sp. since only extracellular stages were observed. Haemohormidi um-like organisms were found in Antimora rostrata taken from 2441 m, and we re similar to those described previously from this deep-sea fish. A VEN-lik e infection from one N. stomias captured from 2567 m was reported. No marke d effects on host cells were evident in any of these blood infections.