The specimens upon which Lecidea petraea var. obscurata Ach., the basionym of Rhizocarpon obscuratum (Ach.) Massal., is based are shown to be mostly referable to the species currently known as R. lavatum (Fr.) Hazslin. Rhizocarpon reductum Th. Fr. is resurrected to accommodate specimens with small ascospores previously referred there. The related species R. sublavatum is described from the Scottish Highlands and descriptions provided for R. anaperum (Vain.) Vain, and R. amphibium (Fr.) Th. Fr. These species are compared with R. reductum, R. lavatum and R. petraeum. Rhizocarpon rubescens Th. Fr. is shown to be a distinct species recorded from Europe and N. America.

Lichenochora mediterraneae Calatayud, Nav.-Ros & E. Calvo (Phyllachorales)a new species of non-lichenized lichenicolous fungi, is described from the provinces of Cádiz and León (Spain)growing on Fuscopannaria mediterranea. is mainly characterised by having bispored asci, and 3–4-septate, narrowly cylindrical or bacilliform spores. The new species is compared with L. clauzadei and L. bellemerei, the two previously known species with pluriseptate spores.

A revision is presented of the sorediate, lecanoric acid-containing Punctelia species occurring in Europe. Two species are common in western andcentral Europe, viz. Punctelia subrudecta s. str. and Punctelia ulophylla comb. nov.They differ in several morphological characters, most notably in the colour andpruinosity of the margin. Both species occur sympatrically, often together on onetree. A third species, Punctelia perreticulata, is known in Europe only from the Mediterranean.

Porina bryophila P. M. McCarthy & Kantvilas is described from living and moribund epiphytic bryophytes in Tasmanian rainforest. The diversity, ecological groups and biogeographical affinities of Tasmanian Trichotheliaceae, currently comprising 25 taxa, are discussed.

The following new species are described: Degelia calcicola P. M. Jørg. & Kantvilas, a squamulose species from wet calcareous rocks in Tasmania; D. Crustacea P. M. Jørg. & D. J. Galloway, a crustose, corticolous species from northern New Zealand; and D. subcrustata P. M. Jørg. & Kantvilas from dry granitic rocks in southern Australia and Tasmania.

Two new fossil species (Parmelia ambra Poinar, E.B. Peterson & Platt and P. isidiiveteris Poinar, E.B. Peterson & Platt) are described from Dominican amber. The potential evolutionary value of lichens preserved in amber is discussed.

The annual course of irradiance was recorded at two vertical and even-aged neighbouring Quercus stems, one rich in L. pulmonaria, one without. Irradiance never exceeded 610 μmol photons m−2 s−1 at the L. pulmonaria site, whereas the L. pulmonaria-deficient site could experience 2 h daily 2000 μmol photons m−2 s−1, and 6 h above 1000 μmol photons m−2 s−1 during a clear day in early spring. Thalli of L. pulmonaria were transplanted to these two stems. During the first 40 days (April–May), transplants at the L. pulmonaria-deficient site developed severe chlorophyll degradation, and a substantial reduction in maximal PS II efficiency (Fv/Fm) even when measured after a 48-h recovery period at low light intensity. Extensive bleaching was formed along light-exposed sides of the tiny ridges on the upper side. Subsequent to this damage, FV/FM gradually rose to nearly normal levels during the following year. This apparent recovery was probably mainly due to irreversible loss of damaged chlorophyll, but also to some level of acclimation. No damage was observed in control transplants on the L. pulmonariarich tree, which were the only transplants gaining sufficient growth for new attachment to the new substratum during the 397-day transplantation period. Nevertheless, a fine-scale, but highly significant seasonal variation in FV/FM of control transplants reflected variations of even low irradiance levels. FV/FM, as measured after a 48-h recovery period at low light intensity, is an efficient meth for recording permanent high light damages at and shortly after damage is formed. However, FV/FM is not a useful estimator of chronic long-term damage.