With its yellow-green colour and wavy-looking leaf margins, you could be forgiven for assuming you’ve found Streblotrichum (Barbula) convolutum var. commutatum or Trichostomum brachydontium instead of Tortella flavovirens.
T. flavovirens it is almost always restricted to open ground very close to the sea, where it can be abundant. It is a member of a distinctive coastal bryophyte community that often includes Scleropodium touretii, Didymodon tophaceus and various Tortula and Weissia species. Like the majority of Tortella species, it has very striking leaf areolation and this will help to confirm its identity. With a fingernail or tweezers, remove a leaf and, while holding it up to the light, view it with a hand-lens. You’ll see that the hyaline basal cells reach up the margin in a diagonal line and contrast sharply with the green, almost opaque cells above.Read the Field Guide account