A Free Ride: Diatoms Attached on Motile Diatoms

Abstract

Periphytic diatoms are known to attach to a wide variety of submerged substrates. This review deals with a very particular substrate that consists of large benthic and motile diatoms. It is about passively motile epidiatomic diatoms. Their mode of attachment is similar to that of epiphytes on macrophytes, so they are also referred to as epiphytes, with the assumption of a negligible impact on the host's fitness. Hostepiphyte relationships are quite specific and concern only a few freshwater species. It is not a random attachment to a neutral substrate, but rather an interaction between species that should at least benefit the epiphytes, in particular through a higher dispersal capacity. Current knowledge of this phenomenon is limited to observations. Further studies are needed to better characterize the nature of this original association between species. They should contribute to the poorly explored field of research concerning direct interactions between diatom species.