Identification notes
In 2017, Heribert Köckinger & Lars Hedenäs published a paper in Journal of Bryology which gave convincing reasons to split Tortella bambergeri into two new species: T. fasciculata and T. pseudofragilis.
T. fasciculata should be suspected if you find a Tortella with the size, habit and broad appearance of T. tortuosa, differing in its narrow-looking and slightly undulate leaves. Microscopically, this species is separated from T. tortuosa in (i) its stem having a central strand (easily seen in transverse section) and (ii) the presence of quadrate, superficial papillose cells on the dorsal surface of the nerve i.e. on the underside in the upper part of the leaf (lacking in T. tortuosa). For differences from the very rare T. pseudofragilis, refer to the resources given below.
The ecology of T. fasciculata in Britain and Ireland is not yet fully understood, but it can quite often be found in sunny, warm situations on base-rich boulders or crags in the uplands. On hard limestone, especially in drier lowland areas, it appears to be replaced by T. tortuosa.
See the old Tortella bambergeri page
