Immersaria olivacea, its lichenicolous fungus Polycoccum decolorans, and Immersaria mehadiana are described as new species from Spain and Romania, respectively. A new combination, Immersaria cupreoatra is proposed, and a revised concept of the genera Bellemerea and Immersaria is supplied. C 1998 The British Lichen Society

An account of the lichen flora of Caenlochan, in the Eastern Highlands of Scotland, is provided; it is considered to be the third most important site for calcico- lous montane lichens in the UK, after Ben Lawers and Ben Alder. After evaluating all records, 322 species are accepted as having been recorded from rock and soil on high ground of which many are reported for the first time. These include Collema parvum and Rinodina parasitica new to the British Isles. The lichen flora is distributed in many small pockets, each of medium interest, so there is no single outstanding site in the corrie. Substratum variability contributes significantly to lichen diversity; the Lawers Calcareous Schists are soft and laced with seams of marble, whereas the harder hornblende schists form high cliffs that carry communities typical of rocks of intermediate base-status. The course of the Glasallt Burn is particularly varied. Severe restraints on the alpine lichen flora include the relatively low altitude (610-850 m) and sheltered situation of the calcareous strata. This adversely affects terricolous and bryophilous species. The outcrops of alkaline rock are severely limited in extent considering the reputation of Caenlochan. This is one of the driest parts of the Highlands; species of unusual abundance, such as Acarospora cervina are probably favoured by the summer water deficit, whereas others, less frequent than expected, for example Amygdalaria spp. and Collema glebulentum, may be restricted by it. Four new taxa are described: Lecidea pycnocarpa f. sorediata Coppins & Fry day, Pertusaria flavocorallina Coppins & Muhr, Polyblastia efflorescens Coppins, and Thelidium papulare f. sorediatum Coppins.

Sphaerophorus diplotypus Vainio is reported as new to mainland Africa (Tanzania). Sphaerophorus digitaius Wang-Yang & Lai is reduced to a synonym of 5. diplotypus. The name Sphaerophorus dodgei Ohlsson is validated and a description of the species is given. Sphaerophorus dodgei is recorded as being widespread and common in the Valdivian rainforest of Chile and Argentina. Sphaerophorus imshaugii Ohlsson is reported as new to the North and South Islands of New Zealand. Sphaerophorus macrocarpus Ohlsson is reported as new to South America (Chile). In S. dodgei and 5. macrocarpus the spore ornamentation consists of mazaedial material added to the spore wall after the spores have been released from the asci. Concentric bodies occur in young ascospores of 5. macrocarpus. A protocetraric-acid-deficient strain of 5. microsporus Ohlsson is reported for the first time. Sphaerophorus tibellii Wedin, from northern New Zealand, is described as new.

Placoparmelia patagonica Henssen gen. et sp. nov. is described from two localities in Argentina. The placodioid thallus of P. patagonica has a primitive paraplectenchymatous upper cortex in parts but is devoid of a clearly defined lower cortex, true rhizines or tufts of rhizoidal hyphae. The upper surface is minutely porous and reacts HNO, + blue-green indicating the presence of glomellifera brown. Norstictic acid with small amounts of connorstictic and cryptostictic acid, and a trace of an unknown substance were detected by TLC. The ontogeny and structure of the apothecia and pycnidia correspond to those of the Parmeliaceae. The anatomy of the thallus in P. patagonica is compared with that in Neofuscelia squamariata, N. pulla and Parmelia saxatilis.