Coralline algae have occurred in the Mediterranean area for about 140 My. Some Mediterranean corallines are key ecosystem engineers that produce or consolidate biogenic habitats (e.g., coralligenous concretions, rhodolith beds, Lythophyllum rims). Although bioconstructions build by corallines exist virtually in every sea, in the Mediterranean they reach a particularly high spatial and bathymetric extent.

This review assessed the state of knowledge for the coralline algae of the Mediterranean Sea, a group of calcareous seaweeds imperfectly known and considered highly vulnerable to long-term climate change.

It is shown that in terms of diversity, 60 species of corallines are currently reported from the Mediterranean. In relation to climate change, it is stated that the responses of Mediterranean corallines to climate change have been the subject of several recent studies that documented their tolerance/sensitivity to elevated temperatures and pCO2. Although the authors state, that these investigations have focused on a few species and should be extended to a wider taxonomic set.

The authors underline that phylogeography, genomics, transcriptomics, and associated microbiomes are fields in which the information for Mediterranean corallines is very limited. It is suggested that future work on Mediterranean corallines should be based on a multidisciplinary perspective combining different approaches, and that it should consist of large-scale efforts by scientists based both in western and eastern Mediterranean areas.

Rindi et al. (2019) Coralline algae in a changing Mediterranean Sea: How can we predict their future, if we do not know their present? Frontiers in Marine Science doi: 10.3389/fmars.2019.00723.