Like several other epiphytic Orthotrichaceae, Lewinskya striata has had a bit of a resurgence in recent years, although still not common and always a pleasure to find. It is usually taller than L. affinis, and even when the moss is not fruiting, the bryologist can be alerted to its presence by its large size and sharply pointed leaves. It shares these features with Pulvigera lyellii, but differs in that there are no brown gemmae on the leaves here and the shoots do not curve away from the tree in the same striking manner.
Capsule characters are needed for confirmation: when dry, the capsules of L. striata are completely smooth, with none of the ribbed appearance of those of L. affinis. In addition, the outer peristome of the dry capsule has 16 clearly separated teeth, which curve back from the capsule mouth in a beautifully neat manner. Those of L. affinis are fused in pairs so appear as 8 such ‘teeth’. The rather curious inner peristome teeth of L. striata are worth a look under the microscope – they have the appearance of roughly hewn blocks of stone piled into tall columns which are just about to topple over. L. shawii looks similar to L. striata but lacks an inner peristome – you are, however, very unlikely to encounter this species in Britain.Read the Field Guide account