Identification notes
This tiny, winter-fruiting pioneering moss has long been hiding in plain sight as some historical collections were wrongly named P. ovatum – a much larger moss with a long, conspicuously hyaline hair-point. It was finally recognised as a British resident in 2015 and does not have an account in the Field Guide.
Unlike P. ovatum, P. papillosum doesn’t form dense hoary patches. In fact very careful hands-and-knees searching of calcareous clay habitat is needed to find it, as it often grows in scattered patches. Without capsules, it is really hard to find as its hair-point is often short and coloured. Look for it in January, when its capsules mature. As its name suggests, a major point of difference from P. ovatum is its strongly papillose leaf cells (P. ovatum has smooth ones, or rarely with low conical papillae). This moss is typically found in grazed clay-rich limestone grassland, often in barish ground on stepped terraces. It can often be found with a number of other interesting species, including Pottiopsis caespitosa, Ephemerum recurvifolium, Entodon concinnus and Aloina aloides.