Identification notes

This page covers the plant now recognised as T. brachydontium s. str. which, with T. herzogii and T. littorale, was segregated from T. brachydontium Bruch in Britain and Ireland in 2024. Until the second edition of the BBS Field Guide is published, the current FG species page refers to T. brachydontium agg.

T. brachydontium s.str. may be recognised in the hand by undulate, usually twisted leaves with acute to acuminate apices and a (usually) long-excurrent nerve. Some variability remains, and there is a continuum of forms between this species and T. littorale. As such, it will not always be possible to name every collection.

For further details, and a key to Trichostomum, see the Resources section of this page.

Distribution in Great Britain and Ireland

The distribution map in the 2014 Atlas is for T. brachydontium agg., so includes all three segregates. As yet, a clear picture of distribution of each of the segregate species has not emerged, apart from T. herzogii, which is more or less restricted to limestone and other hard calcareous substrates on sheltered crags and gorges. A preliminary distribution map of each of the three segregates is included in the 2024 Field Bryology article.