Species identification Gyrodactylids are ubiquitous monogenean ectoparasites on the skin and gills of teleost fish both in marine and freshwater ecosystems. The most recent species compilation lists some 400 gyrodactylid species. Gyrodactylus salaris is a species of this genus found on fins and skin of Atlantic and Baltic salmon in its freshwater phase (Figure 1). The small (0.5 1 mm) parasite ...

We developed a rapid effective method for accurate estimation of intensity for the monogenean Lepidotrema bidyana, a gill parasite of silver perch Bidyanus bidyanus. This parasite requires monitoring because high-intensity infections reduce host growth and can lead to secondary bacterial and fungal infections. The most accurate method for counting L. bidyana was visual examination of fresh gill...

1. Parasites comprise a substantial proportion of global biodiversity and exert important ecological influences on hosts, communities and ecosystems, but our knowledge of how parasite populations respond to human impacts is in its infancy. 2. Here, we present the results of a natural experiment in which we used a system of highly successful marine protected areas and matched open-access areas i...

In many species male sexual characteristics are known to be affected negatively by parasites, which render their hosts unattractive to females, but how parasites affect the mating decisions of their female hosts has received little attention. The monogenean parasite Gyrodactylus turnbulli reduces the sexual display and colour intensity of male guppies, Poecilia reticulata, which makes them less...

To better understand the spread of disease in nature, it is fundamentally important to have broadly applicable model systems with readily available species which can be replicated and controlled in the laboratory. Here we used an experimental model system of fish hosts and monogenean parasites to determine whether host sex, group size and group composition (single-sex or mixed-sex) influenced h...

The goals of this paper were to investigate phylogenetic and evolutionary patterns of cichlid fish from West Africa and their Cichlidogyrus and Scutogyrus monogenean parasites, to uncover the presence of host-parasite cospeciation and to assess the level of morphological adaptation in parasites. This required the following steps, each one representing specific objectives of this paper: (1) to b...

Five specimens of Xiphias gladius Linnaeus, 1758 were sampled from the eastern coast Algeria and examined for their metazoan parasites. Pathological effects collected parasites whole body X. gladius. Four species collected: two monogeneans (Tristoma coccineum Cuvier, 1817; T. integrum Diesing, 1850), one copepod (Pennella instructa (Wilson, 1917)) parasitic nematode (Hysterothylacium aduncum (R...

Heterogeneous exposure to parasites may contribute host species differentiation. Hosts often harbour multiple parasite which interact and thus modify each other’s effects on fitness. Antagonistic or synergistic interactions between be detectable as niche segregation within hosts. Consequently, the within-host distribution of different taxa constitute an important axis infection variation among ...

Between March 2000 and April 2001, 63 specimens of N. barba from Angra dos Reis, coastal zone of the State of Rio de Janeiro (23 degrees 0' S, 44 degrees 19' W), Brazil, were necropsied to study their infracommunities of metazoan parasites. Fifteen species of metazoan parasites were collected: 2 digeneans, 1 monogenean, 2 cestodes, 1 acantocephalan, 2 nematodes, 6 copepods, and 1 hirudinean. Ni...