Neil Sanderson

More on Lecanora hybocarpa.

I recently collected a recently dead Aspen branch from Ashurst Wood on the open New Forest and went through it at leisure. This added Caloplaca cerinella, with c 16 spores in the asci, probably common in the wider countryside but new to the open Forest.

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Caloplaca cerinella on dead Aspen branch

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Caloplaca cerinella apothecia squash showing asci with more than 8 spores.

The main interest, however, was that all the Lecanora on the branch looked at had Lecanora hybocarpa type apothecia with a Lecanora pulicaris type distribution of crystals in the both epithecium and into the upper part of the hymenium, but with a Pd – thalline margins. The forms were varied, however, some with very large crystals in the thalline margin, giving very rough margins

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Lecanora hybocarpa on Aspen branch with rough thalline margins. These rough margins are quite frequent on Lecanora species on Aspen for some reason.

Others had the thallus covered in apothecia initials, giving Lecanora sinuosa, which may just be a morph of Lecanora hybocarpa.

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Lecanora sinuosa on Aspen branch, with thallus covered by apothecia initials

As well as this I have recently being doing some planning work in ordinary south Hampshire countryside outside of the New Forest. This has given me the opportunity to sample lots of Lecanora species from twigs and hedgerow trees. Interestingly Lecanora hybocarpa proved to be widespread on the twigs, commoner than Lecanora chlarotera, which was also present. Also seen were quite a collection of Lecanora species on bark and wood: Lecanora argentata, Lecanora sinuosa, Lecanora horiza, Lecanora albella, Lecanora carpinea, Lecanora barkmaniana, Lecanora pulicaris, Lecanora conizaeoides f. conizaeoides, Lecanora symmicta, Lecanora expallens and Lecanora compallens. The latter was found fertile on some dead wood. This has only recently been found fertile, so I will put up some pictures when I have looked at it fully. There are at least two distinct morphs of Lecanora chlarotera as well: a form with pale disks and an off white thallus and smaller spores (every where, including trunks) and one with chestnut disks, a white thallus and some what larger spores (mainly branches, where it looks like Lecanora argentata, which occurs more on trunks but can occur on branches). The latter could potential be another cryptic species but this would need DNA sequencing to ascertain (Pictured with Lecanora hybocarpa, on an Oak twig, Matley Wood, New Forest in my first post).

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Lecanora hybocarpa from Oak twig in hedgerow in farmland, the faintly pruinose disk is a good lead for likely Lecanora hybocarpa specimens.

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Lecanora hybocarpa from Oak twig apothecia cross section in water in normal light

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Lecanora hybocarpa from Oak twig apothecia cross section in water in polarised light

Finally I am just back from a job in North Wales, where I also did some Lecanora species sampling. Only Lecanora chlarotera and Lecanora argentata here, so it may be that Lecanora hybocarpa is a southern and eastern species in Britain.