Like the two other Entosthodon species of limestone, this nationally scarce moss does not yet have an account in the Field Guide. However, it is a relatively conspicuous species (when capsules are present, that is!) and almost entirely restricted to disturbed, thin soil around sheltered limestone exposures. It often grows in a community of other pioneering bryophytes, such as Bryoerythrophyllum ferruginascens, Riccia species, Tortula lindbergii, Pleuridium subulatum and Weissia brachycarpa var. obliqua.
April or May is the optimal time to seek out E. pulchellus. In spring, the capsules will be mature and identification straightforward. Beware earlier collections – immature capsules are covered by a large calyptra which can give a misleading impression of asymmetry.
E. pulchellus differs from all our other species in the genus, except E. muhlenbergii, in having an inclined, asymmetrical capsule with an oblique mouth and double peristome. The cells at the margin of the lid are red, or orange-red, and contrast with the other cells of the lid. Be sure to double-check the leaves – E. pulchellus has entire margins while those of E. muhlenbergii are distinctly toothed above.