Stirtonia byssoidea, S. coei and S. latispora, all from coastal hammocks within Everglades National Park, are described as new to science. Stirtonia byssoidea is characterized by a felty byssoid thallus, conspicuous immersed white pruinose-like lirelliform ascigerous zones, small ascospores and the presence of perlatolic acid. It is closest to S. alba but has a different thallus type and much smaller ascospores. Stirtonia coei is recognized by its lirellate ascigerous zones raised well above a greyish crystallate thallus, large ascospores and a lack of chemistry. It is closest to S. curvata but differs by its I+ blue thallus, strongly raised ascigerous zones and by having no lichen substances. Stirtonia latispora can be identified by its white lirelliform ascigerous areas immersed in a greyish green thallus, large, broad ascospores with a conspicuously enlarged mid cell and lack of substances. It would also key out close to S. curvata but differs by the aforementioned ascigerous zones, an I+ blue thallus, wider ascospores with a different locular configuration and its lack of chemistry. A key to the six species known from the Neotropics is also provided.

Eugeniella palleola, Graphis paraschiffneri, and Malmidea cineracea are described from Nicaragua. Eugeniella palleola is characterized by having pale apothecial discs and prominent, white margins, and producing a complex chemistry including atranorin, stictic and norstictic acids, and an unknown substance. Graphis paraschiffneri has lirellae with a lateral thalline margin, striate labia, a completely carbonized excipulum, transversely septate ascospores, and contains norstictic acid in the thallus. Malmidea cineracea is characterized by a granulose-isidiate thallus with a yellowish medulla and a compact, crystal-encrusted excipulum. Malmidea nigromarginata and M. piperina are proposed as new combinations. Keys are presented to all known species of Eugeniella (9) and Malmidea (50).

A new corticolous lichen species Ramonia variospora is described from Brazil. It has a verrucose thallus, concave, initally almost closed apothecia and variably 8 or c. 32–64, 1-septate ascospores per ascus; when 8 per ascus, ellipsoid and 16–22×6–10 µm; when c. 32–64 per ascus, broadly ellipsoid and 10–14×6–8 µm. A revised world key is given to all currently known species of Ramonia.

Allocetraria yunnanensis R. F. Wang, X. L. Wei & J. C. Wei is described as a new species from the Yunnan Province of China, and is characterized by having a shiny upper surface, strongly wrinkled lower surface, and marginal pseudocyphellae present on the lower side in the form of a white continuous line or spot. The phylogenetic analysis based on nrDNA ITS sequences suggests that the new species is related to A. sinensis X. Q. Gao.

Molecular inferences of three loci within a phylogenetic framework of a subset of the Pannariaceae confirm that the genus Kroswia is nested within the genus Fuscopannaria. The formal combination of the type species of Kroswia into Fuscopannaria is therefore made here, and Kroswia is reduced into synonymy with the latter genus.

The phylogenetic position of the genus Pseudoparmelia was addressed using molecular data from five loci (mtSSU, nuLSU, ITS, Mcm7, RPB1), generated from three species and aligned with sequences from 293 samples representing all major clades of Parmeliaceae. Pseudoparmelia species form a well-supported monophyletic group that is the sister group of a clade consisting of the genera Relicina and Relicinopsis. These three genera share a thallus with a pored epicortex, isolichenan as cell wall polysaccharide, and relatively small ascospores. Morphological and chemical characters that distinguish Pseudoparmelia from the closely related Relicina and Relicinopsis are discussed. To further elucidate the relationships of these three genera, we assembled a second dataset including 15 additional samples of Relicina and Relicinopsis using three loci (mtSSU, nuLSU, ITS). All three genera are monophyletic but monophyly of Relicina lacks support and, in the mtSSU single locus tree, the genus is paraphyletic with Relicinopsis nested within. Additional studies including more Relicina species are necessary to test delimitation of the genera Relicina and Relicinopsis.

Very little is known about how growth is distributed within thalli of fruticose lichens. To determine whether mature, non-apical regions of the beard lichen Ramalina usnea elongate, segments of the broadest axes were marked with thread and measured; thalli were then returned to the field to resume growth for about one year. Growth was evident in all segments measured and increments were roughly proportional to length, suggesting that elongation occurs throughout the thallus. New thallus axes (branches) were organized from buds that emerged from mature tissue, usually along pseudocyphellae and surfaces exposed by breakage. Axes were very fine at their extremities and possessed an inrolled apex from the time of bud emergence. No evidence of apical branching was observed. The thallus cortex consisted of very thick-walled fungal cells oriented longitudinally. In transverse section, cells gave the appearance of being grouped within fascicles, indicating that branch cells grow within the older cell wall material of their neighbours, as occurs in the cortex of Ramalina menziesii and the medullary cord of Usnea longissima. A continued accumulation of cell wall layers may be related to the mature tissue's capacity to sustain elongation growth.

For a long time, agriculture and recurrent fires have been the main factors promoting diversity changes in Mediterranean areas. We examined the effect of irrigated and non-irrigated crops and fires on the epiphytic lichen diversity of holm oak trees in the Vall d'Albaida region (Valencia, Spain). Lichen diversity was studied by calculating the LDV (Lichen Diversity Value) and the proportion of functional groups. No significant differences were observed between areas located near irrigated or non-irrigated crops. Fire-affected areas tended to harbour lower LDV and species richness than those influenced by agriculture. By using lichen functional groups, it has been shown that eutrophication tolerance, substratum pH affinity and, to some extent, thallus growth form are the main factors driving epiphytic lichen diversity in this rural area.

The genus Hypogymnia is morphologically characterized by swollen lobes, a hollow medulla, perforations in the lower surface, and the absence of rhizines. In our studies on Hypogymnia spp. we found rhizines and hapters were occasionally present on the lower surface of 35 species. Morphology and anatomy of the appendage-organs were studied using dissecting, compound, and scanning electron microscopy and compared with rhizines found in the related genus Arctoparmelia. Two types of rhizine-like structures were found in Hypogymnia: slender and elongated rhizines, and thick and short hapters, both of which were few in number and sparsely distributed on the lower surface. There are no obvious differences in the morphology of rhizines between Arctoparmelia and Hypogymnia, except that rhizines are abundant in Arctoparmelia. Within Parmeliaceae, Hypogymnia belongs to the hypogymnioid clade together with the genera Arctoparmelia, Brodoa, and Pseudevernia, most of which are considered to lack rhizines. The occurrence of rhizines in Hypogymnia is consistent with the placement of Arctoparmelia in the hypogymnioid clade based on molecular data.