World distribution: Leptogium cochleatum is known from India, East Africa, the Azores, Italy, Corsica, the former Yugoslavia, and western Europe from Portugal to western Norway (Jørgensen & James 1983, Swinscow & Krog 1988, Nimis 1993, Tønsberg 1994). In northwest Europe the species shows a western British Isles - western Norway disjunct distribution. In Fennoscandia it is restricted to Norway
Ecology: Results. Leptogium cochleatum has only been found on old, pollarded, shaded trunks of Fraxinus excelsior in a northeast-facing pasture-woodland in an old agricultural landscape. The species occurred over mosses or, more rarely, on naked bark, sometimes on the rather dry underside of slightly leaning trunks. The site (3770) was particularly rich in ancient woodland species, among the most noteworthy were the oceanic species Gomphillus calycioides, Leptogium burgessii, L. hibernicum, Megalospora tuberculosa, and Rinodina isidioides (see also Tønsberg 1994). Discussion. Leptogium cochleatum is a species of old, pollarded, more or less moss covered trunks of Fraxinus excelsior. It is thus restricted to the old agricultural landscape. Apparently it is an indicator species of ancient woodlands. According to Jørgensen & James (1983), Leptogium cochleatum is a species of moss covered trees and rocks, usually in shaded, rather humid situations, often near streams. In the British Isles it grows particularly on old Fraxinus or Corylus in sheltered habitats
Threats: Results. Recorded threats were lack of active pollarding, road construction, and planting of Picea (two Picea-thickets were observed within the site)
Status: The locality was discovered and investigated in 1993-1994. The species has been observed on c. 5 trunks. On several trunks a number of thalli occurred. The locality is not protected
Specimens in other herbaria, litterature, etc.