Three species are known to occur in UK freshwaters: Argulus foliaceus, Argulus coregoni and Argulus japonicus. Two of these species, A. foliaceus and A. coregoni, are considered native to the UK (Fig. 1). These indian email address list species are easily discriminated as adult A. coregoni are more than twice the size of adult A. foliaceus and have pointed rather than rounded abdominal lobes. A. japonicus is thought to be non-native and introduced from Asia through the ornamental trade. This species closely resembles A. foliaceus and can only be discriminated at a microscopic level.
Figure 1. Ventral view of adult A. coregoni and A. foliaceus.
A. foliaceus is widely recorded throughout the world, typically inhabiting nutrient-rich lakes, although it can tolerate salinities of up to 8–12 ppt at temperatures up to 25°CA. coregoni infects fish in cold oligotrophic rivers, streams and lakes with a high flow rate. A. japonicus is recorded throughout Europe, Africa, North America and Asia. At present, records of A. japonicus are limited in the UK, and due to the difficulty in differentiating the two species it may have been misidentified as A. foliaceus in some cases.
Many early records of Argulus spp.