Boccardia proboscidea (Polychaete: Spionidae) from SW Atlantic: how far has the 5 invasion spread?

Abstract

Boccardia proboscidea, an exotic polychaete species has been introduced in a Southwestern Atlantic Ocean coastal area of Argentina (Mar del Plata; Province of Buenos Aires). This polychaete proved to be a threat to local diversity as it displaced native species and modified the intertidal natural community structure. However, anything is known about their latitudinal distribution in the country and the degree of its invasion. It is probable that for deficiencies in the taxonomy or lack of ecological studies, other localities of the Argentine coast are also invaded by this polychaete and have not been registered from to date. The goal of the present study was to survey the latitudinal distribution of B. proboscidea in the coastal area of Argentina from 37° S to 54°S. In addition, were also aims to evaluate the type of colonized substrate; to establish if the presence of a sewage effluent is a conditional factor for B. proboscidea development and to evaluate the differences in the composition of intertidal species assemblages associated to the community invaded by the polychaete. B. proboscidea was found latitudinally until 47°S and the highest abundance was found on beaches with hard substrates and with an intertidal sewage effluent. The opportunistic nature (strategist r) of B. proboscidea coupled with a continuous supply of organic matter (sewage effluent) could explain the possible mechanism that led to the success of its introductions into new localities.