Abstract The Peripampasic Arc is a set of low mountains / hills that connects the Andes, as it scatters to the East forming mountainous areas of lower heights in north-eastern Argentina, with the Atlantic coastal range of the Serra do Mar in Brazil. Numerous studies proved its important biogeographic connection for plant and animal phylogenies, but no information of this pattern is known to lichens. The aim of this work is to establish if the dispersion route of the lichenbiota follows the previously known Peripampasic Arc. For this reason, a comparative study of each area regarding its similarities was analyzed, with emphasis on the biota of the Buenos Aires’ Sierras. We quantified the similarity and β diversity of 104 saxicolous lichens species. There was a strong similarity between the Sierra de la Ventana and Tandil biota, which in turn is linked to the biotas of Uruguay, the Pampean Sierras and the northwest of Argentina. The lack of subgroups in the Peripampasic Arc implies the arc acts as a functional unit of dispersion, which is the most likely cause for the present lichens’ distribution.

Verrucaria aethiobola is a cosmopolitan lichen of freshwater previously cited in Argentina from Neuquén province. In this study, it is recorded for the first time from Buenos Aires province. A description of the species, illustration of the specimen, and comments on its ecology and geographical distribution are presented.

Verrucaria aethiobola es un liquen cosmopolita de agua dulce que previamente fue citado en Argentina para la provincia de Neuquén. En este trabajo se cita por primera vez para la provincia de Buenos Aires, aumentando su distribución conocida. Se presenta una descripción de la especie, imagen del espécimen y comentarios sobre su ecología y distribución geográfica.

The Institute of Botany Carlos Spegazzini (IBCS) (UNLP, La Plata) hosts an herbarium of fungi (LPS) of approximately 40,000 specimens, with 4200 type specimens. The aim of this study was to examine the specimens of lichenized fungi deposited in the IBCS, update their taxonomy and name, check questionable species determination, identify those not certain, and incorporate them into the Herbarium LPS. 192 specimens were studied coming from 11 Provinces of Argentina, as well as Brazil, Uruguay and France and they were determined based on their exo-morphology, histological and histochemical reactions. Thin Layer Chromatographs (TLC) were also performed to study the secondary metabolites present. Argentinean geographical distribution of the identified species was established. The 91.66% of the materials examined (176 specimens) was corrected and accounted for a total of 91 species, 50 genera and 21 families, with Parmeliaceae (16 genera, 31 species), Graphidaceae (4; 5) and Physciaceae (3; 9) as the best represented. The name of 56 specimens belonging to 32 species was updated. The identity of 120 specimens was modified to species level (87), genera (33) and family (1). The distribution of 9 species in Argentina was expanded.

El Instituto de Botánica Carlos Spegazzini (IBCS) (UNLP, La Plata) contiene un herbario de hongos (LPS) de aproximadamente 40000 ejemplares, con 4200 especies tipo. El objetivo de este trabajo fue examinar los ejemplares de hongos liquenizados depositados en el IBCS, actualizar su taxonomía y denominación, revisar las especies con determinación dudosa, identificar aquellos no determinados, e incorporarlos en el Herbario LPS. Se estudiaron 192 ejemplares de 11 provincias de Argentina y de Brasil, Uruguay y Francia y de se determinaron en base a su exo-morfología, cortes histológicos y reacciones histoquímicas. También se realizaron Cromatografías en Capa Delgada (TLC) para estudiar los metabolitos presentes. Se estableció la distribución geográfica en Argentina de las especies identificadas. Se corrigió el 91,66% de los materiales examinados (176 ejemplares), contabilizándose un total de 91 especies, 50 géneros y 21 familias, siendo las mejor representadas Parmeliaceae (16 géneros; 31 especies), Graphidaceae (4; 5) y Physciaceae (3; 9). Se actualizó la nominación de 56 ejemplares pertenecientes a 32 especies. Se modificó la identidad de 120 ejemplares, a nivel de especie (87), género (33) y familia (1). Se amplía la distribución en Argentina de 9 especies.