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confirms findings from an earlier study also conducted at multiple          Sclafani for his help with the graphs. We also wish to acknowledge
locations, in which the maximum magnitude of difference was
about 70% (Giovannetti et al., 2008).                                     the anonymous reviewers and the editor for their very helpful

    Previous studies highlighted that substratum typologies may           comments and fruitful suggestions, which greatly assisted us in
explain the observed variation in P. oceanica descriptors at a scale of
tens of kilometers (Balestri et al., 2003). Here, we show that this       improving the manuscript.
source of variation is also potentially present at a smaller scale,
since different substratum typologies may occur within the same           References
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