The prevalence of parasitic pea crab Afropinnotheres monodi in mussels depending on the degree of exposure of habitats: implications for mussel culture

Abstract

As many other Pinnotherid crabs, the African pea crab Afropinnotheres monodi live in association with the mantle cavity of different bivalve species. This pea crab causes a significant reduction of the condition index of the mussel Mytilus galloprovincialis. The greatest effects brought about for the infestation with soft females (larger size and obligatory parasitism) and/or multiple infestation (two or three pea crab inside the same host); whereas erosion of the gills and mantle of hosts have been also observed in mussels and cockles (Cerastoderma edule) infested by hard females and males which have smaller size than soft females and are facultative parasites (Perez-Miguel et al. 2018). To test the hypothesis that the prevalence of this pea crab in subtidal mussels depends on the degree of exposure/shallowness of their habitats and consequently of the coexistence of hosts of all crab demographic categories in a reduced area, in this study we assess the prevalence and demographic structure of A. monodi in the subtidal mussels attached to the submerged chains of the navigational buoys (lateral marks) of the Port Authority located along the navigable channel of the bay of Cadiz.