diversity Article Cross Taxon Congruence Between Lichens and Vascular Plants in a Riparian Ecosystem Giovanni Bacaro 1,* , Enrico Tordoni 1 , Stefano Martellos 1 , Simona Maccherini 2 , Michela Marignani 3 , Lucia Muggia 1 , Francesco Petruzzellis 1 , Rossella Napolitano 1, Daniele Da Re 4, Tommaso Guidi 5, Renato Benesperi 5 , Vincenzo Gonnelli 6 and Lorenzo Lastrucci 7 1 Department of Life Sciences, University of Trieste, Via L. Giorgieri 10, 34127 Trieste, Italy 2 Department of Life Sciences, University of Siena, Via P.A. Mattioli 4, 53100 Siena, Italy 3 Department of Life and Environmental Sciences, Botany Division, University of Cagliari, Viale S. Ignazio, 13, 09123 Cagliari, Italy 4 Georges Lemaître Institute for Earth and Climate Research, Université catholique de Louvain, Place Louis Pasteur 3, 1348 Louvain-la-Neuve, Belgium 5 Department of Biology, University of Florence, Via G. La Pira 4, 50121 Florence, Italy 6 Istituto di Istruzione Superiore “Camaiti”, Via San Lorenzo 18, 52036 Pieve Santo Stefano, Arezzo, Italy 7 University Museum System, Natural History Museum of the University of Florence, Botany, Via La Pira 4, 50121 Florence, Italy * Correspondence:
[email protected]; Tel.: +39-040-5588803 Received: 23 February 2019; Accepted: 6 August 2019; Published: 13 August 2019 Abstract: Despite that congruence across taxa has been proved as an effective tool to provide insights into the processes structuring the spatial distribution of taxonomic groups and is useful for conservation purposes, only a few studies on cross-taxon congruence focused on freshwater ecosystems and on the relations among vascular plants and lichens. We hypothesized here that, since vascular plants could be good surrogates of lichens in these ecosystems, it would be possible to assess the overall biodiversity of riparian habitats using plant data only.