Tortula protobryoides R.H.Zander

Osman, Imen Ben, Hugonnot, Vincent, Muller, Serge D. & Daoud-Bouattour, Amina, 2021, Four bryophytes collected in Tunisia, new for mainland Africa, Cryptogamie, Bryologie 20 (16), pp. 213-219 : 217

Tortula protobryoides R.H.Zander

SPECIMEN EXAMINED. — Tunisia, Tunisian Dorsal, Siliana Governorate, Delegation of Kesra: Kesra-Plateau (35°49’31.03”N, 09°21’50.13”E, 1069 m a.s.l.; site 2020-17), 11.III.2020, leg. Imen Ben Osman, Vincent Hugonnot, TUN2020-7.

DISTRIBUTION. — Widespread in Europe including Macaronesia, rare in the Mediterranean region ( Ros et al. 2013; Hodgetts & Lockhart 2020); W Asia ( Kürschner & Frey 2020); NW America ( Zander & Eckel 2007).

FLORISTIC ELEMENT. — European temperate.

HABITAT

In grykes of horizontal karstic pavement, on a compacted substrate, in a ruderal habitat, subjected to strong overgrazing. The vascular vegetation comprises a rupicolous community anchored on rock outcrops, mixed with a very degraded holm oak forest ( Quercus ilex subsp. ballota ) characterised by numerous grazing-resistant species.

In Europe, Tortula protobryoides also grows in calcareous habitats on compacted soil, chalky banks, tracks, and paths, and chalky soil disturbed by roads (Blockeel et al. 2014). In Tunisia, associated species are ruderal: Bryum argenteum Hedw. , Didymodon acutus (Brid.) K.Saito and Microbryum Schimp.spp.

Tunisian colonies were fertile (a few sporophytes present). The species was very scattered, with only a few stems.

As a pioneer species, Tortula protobryoides may certainly benefit from being trampled by grazing stocks, but for the Tunisian population, overgrazing is particularly intense and may not be compatible with the long-term conservation even of taxa adapted to disturbance. Monitoring would be desirable in such a situation to determine whether T. protobryoides can withstand such destructive grazing.

COMMENTS

Tortula protobryoides is mainly characterised by sporophytic characters. It has a relatively short seta, making ovoid urn slightly exceeding upper perichetial leaves, and stegocarpic capsules, with rudimentary peristome and persistent rostrate operculum ( Guerra 2006).