Orthotrichum comosum F.Lara, R.

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 : 180-181

Orthotrichum comosum F.Lara, R. Medina & Garilleti

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[TUN2019-291]).

REMARKS

Orthotrichum comosum was found growing on the bark of Quercus canariensis on the banks of a wadi (see Fissidens fontanus for the site description). In Europe, this species is mainly an epiphyte that prefers a relatively exposed habitat. It occurs usually in open woods or on isolated trees ( Medina et al. 2013).

The taxonomic revision of Orthotrichum tenellum s.l. by Medina et al. (2013) led to the recognition of six morphologically distinct species. Among those, O. comosum was described as a new species characterized by its linear or ovate-acute leaves, acute to acuminate but not channeled apices, never rounded or cucullate. The capsule is immersed, with a naked vaginula or only sparse hairs. The exostome teeth are triangular, not truncate and the OPL is ornamented with vermicular lines (it is papillose in O. tenellum ). The calyptra bears an apical tuft of robust erect hairs (these are more regularly distributed in O. tenellum ).

Orthotrichum comosum is a Mediterranean-Macaronesian species restricted to Europe including Macaronesia ( Hodgetts & Lockhart 2020), and present in North Africa ( Medina et al. 2013).