![](https://sciencepress.mnhn.fr/sites/default/files/periodiques/visuels/grand/bryologie-grand-visuel-v2.jpg)
22 taxa of Ricciaceae are known from the Massif Central : Riccia beyrichiana, R. bicarinata, R. bifurca, R. canaliculata, R. cavernosa, R. ciliata, R. ciliifera, R. crozalsii, R. fluitans, R. glauca, R. gougetiana, R. gougetiana var. armatissima, R. huebeneriana, R. macrocarpa, R. michelii, R. nigrella, R. rhenana, R. sorocarpa, R. subbifurca, R. trichocarpa, R. warnstorfii and Ricciocarpos natans. After providing a list of new localities, the author gives a synthesis of his prospections mainly focused on the best known departments, Haute-Loire and Ardèche. He then outlines the altitudinal and geographical distribution of these liverworts and gives precise data on habitat preferences of each species. The high valley of Allier, Cévennes and Chaux of the Puy-de-Dôme are richly provided with Riccia. The richest biotopes of Riccia are pools and edges of pools, artificial or natural temporary seepages and ponds, xerothermophilous lawns and stubbles.