Riccardia chamedryfolia (With.) Grolle

Osman, Imen Ben, Hugonnot, Vincent, Muller, Serge D. & Daoud-Bouattour, Amina, 2022, New bryophytes for Tunisia (North Africa). Part 2: other families, Cryptogamie, Bryologie 20 (11), pp. 173-185 : 176

Riccardia chamedryfolia (With.) Grolle

SPECIMEN EXAMINED. — Tunisia. Mogods, Beja Governorate, Delegation of Nefza: Khorguelia, with sporophytes, 37°04’35.24”N, 09°03’32.75”E, 93 m a.s.l. (site 2019-79), 09.IV.2019, Ben Osman & Hugonnot (TUN[TUN2019-127]).

REMARKS

Riccardia chamedryfolia was collected on wet organic substrate on the banks of a wadi (see Fissidens fontanus for the site description). In other regions, this liverwort occurs on damp to wet substrates in shaded to exposed habitats where it grows on the ground or on tree roots. It can behave like a hydrophyte in wet mires, swamps or along rivers ( Paton 1999; Damsholt 2002). Riccardia multifida , previously mentioned in Tunisia ( Ros et al. 2007), seems to have ecological requirements similar to those of R. chamedryfolia (Jovet-Ast & Bischler 1971) . Both are probably strongly linked to the most humid habitats of Tunisia, namely the main riverbeds of permanent waterways.

Riccardia chamedryfolia is characterized by the distribution of oil bodies within the epidermal cells. At the thallus apex, the oil bodies spread over the entire width of the lobe. The branches do not have clear wings, with the marginal cells of the thallus barely protruding.

The previous report of Riccardia chamedryfolia by Ros et al. (2007) was based on collections published before 1962 and considered dubious because of a possible confusion with R. multifida . The present report can thus be considered the first reliable mention for Tunisia.

Riccardia chamedryfolia is a European boreo-temperate species widespread in Europe, including Macaronesia ( Hodgetts & Lockhart 2020), also present in North Africa( Ros et al. 2013), Asia ( Russia, Konstantinova et al. 2009; China, Piippo 1990; and Japan, Yamada & Iwatsuki 2006) and North America (Faubert 2015).