Identification notes
Until 2005, Tortula subulata was considered to be a (relatively) easily identified species with four recognised varieties (including the nominate var. subulata) accommodating its variability (see Smith’s Moss Flora of Britain and Ireland, 2004).
Then, research showed that the other three varieties – var. angustata, var. graeffii and var. subinermis – could not be maintained as distinct taxonomic entities. However, a new species was recognised within material named as var. angustata and considered it worthy of species status. This is now known as Tortula schimperi and, although scarce, it is easily overlooked as T. subulata. The key differences are in leaf border thickness (one cell thick in T. subulata and 2-3 cells thick in T. schimperi) and width of mid-leaf cells (15-20 um in T. subulata but 10-16 um in T. schimperi).
An account of Tony Smith’s revision of British specimens of T. subulata var. angustata was published in Field Bryology in 2008 and can be downloaded below.
Read the Field Guide account
