Harpidium longisporum is proposed as a new species. It is characterized by an areolate, mainly black thallus with trebouxioid algae, K+ blue-purple pigmented parts, pycnoascocarps forming aspicilioid apothecia, with moniliform paraphyses, unitunicate-rostrate, thick-walled asci and long sigmoid, lunate to falcate or irregularly curved and twisted ascospores, growing on steps of a vertical, intermittently moist, gneiss rock face. The genus Harpidium now comprises four species worldwide and, based on the selected specimens, a genus synopsis, a comparative table and a key to the species are included.

Normandina acroglypta, as recently circumbscribed, is shown to comprise two species: N. acroglypta s. str. with subsquamulose marginal areoles, two unidentified terpenoids by thin-layer chromatography, and growing over rock; and N. chlorococca, with convex marginal areoles, zeorin or no substances detected by thin-layer chromatography, and growing over bark. Normandina dictyospora is newly described from the Falkland Islands and is characterized by relatively large, submuriform ascospores, and no substances detected.

An investigation of the genus Usnea, in the biodiversity hotspot of the Republic of São Tomé and Príncipe in tropical West Africa, is presented here. Fifteen species, or species aggregates, were recorded for the islands: Usnea articulata aggr., Usnea baileyi (Stirt.) Zahlbr., Usnea beckeri P. Clerc & Nadel, Usnea bicolorata Motyka, Usnea erinacea aggr., Usnea exasperata (Müll. Arg.) Motyka, Usnea firmula (Stirt.) Motyka, Usnea krogiana P. Clerc, Usnea longiciliata P. Clerc & Nadel, Usnea nodulosa Swinscow & Krog, Usnea pectinata aggr., Usnea sorediosula Motyka, Usnea submollis J. Steiner, and two undetermined species. Two species of lichen are described as new to science: U. beckeri and U. longiciliata. Both species are characterized by a dense and brittle, dark green thallus, the presence of apothecia surrounded by long cilia-like fibrils, a lack of soredia, and the presence of two unknown substances; however, whereas U. beckeri has a pendant growth form and can reach 25 cm in length, U. longiciliata is differentiated by a shrubby growth form of less than 6 cm. These two species also have different ascospore dimensions. A molecular phylogenetic analysis is presented that lends support to their description as new species. Additionally, Usnea krogiana is noted as new to continental Africa and nine Usnea species or aggregates are noted as new to the Islands of São Tomé and Príncipe in the Gulf of Guinea.

Hysterium graphideum Speg. is proposed as a synonym of Gloniella graphidoidea Rehm. During the study of the types of both names, the presence of algae associated with the fungal hyphae was found. The main morphological and anatomical characters, and the ecology of the species are presented.

The question of whether or not some Trebouxia species have multinucleate cells is a controversial one. Trebouxia jamesii was re-examined and found to have multinucleate cells in cultures grown on rich, organic media. Possible reasons for this condition are discussed.

Two new species are described: .Megalospora occidentalis Kantvilas from Western Australia, with solitary muriform ascospores; M. pulverata Kantvilas from Tasmania, with typically two-spored asci and bicellular ascospores. The new combination M. melanodermia var. galactocarpa (Zahlbr.) Kantvilas is proposed. Megalospora taylori Dodge, described from Tasmania, is a synonym of M. gompholoma subsp. fuscolineata Sipman. New records are reported for Megaloblastenia flavidoatra(Nyl.) Sipman (from Tasmania), .Megalospora disjuncta Sipman (from New South Wales and Queensland), and M. subtuberculosa (Knight) Sipman (from New South Wales). Additional data for Austroblastenia pupa Sipman, M. gompholomasubsp. fuscolineata Sipman and M. lopadioides Sipman, and a key for the family in Australia are presented. M. disjuncta Sipman is lectotypified. Biogeographical and ecological patterns are discussed briefly.

A new corticolous species belonging to the lichen family Pertusariaceae, Pertusaria grassiae Messuti & A.W. Archer, is described from Tucumán Province, Argentina. It is characterized by disciform apothecia covered by a white to greyish white pruina, single-spored asci, ellipsoid and double-walled ascospores and the presence of atranorin.