Recherche scientifique MNHN

Research project

Taxonomy and Ecology of the Lichen Genera Cladina and Cladonia
at Luxembourg

Project leader: José-Manuel Cepeda (Department of Botany, Museum of Natural History, Luxembourg, jmcepeda@mnhn.lu)

Cladina and Cladonia are two very complex lichen genera containing some of the most conspicuous species of Luxembourg’s lichen flora. In general, the taxonomic status of the great majority of their species is correctly defined. However, although sometimes recognised at the species level, there are species groups whose taxonomic rank remain unclear. On the other hand, both genera show a great polymorphism as at genus level as at species level. This high plasticity (inter- and intra-specific) may be an adaptive response to different ecological factors (e.g. substratum, light, humidity) when they are growing in one or several dynamic habitats.

Up to the present, the studies about Cladina and Cladonia carried out at Luxembourg show some taxonomic and ecological gaps. Thus, the main purpose of the current project consists of the resolution of these problems. In this sense, the exhaustive sampling of lichens in a typology of habitats (e.g. forests, heathlands, grasslands, artificial landscapes) widespread throughout Luxembourg, will allow a suitable:

Recognition and description of taxa sampled, with special emphasis in the resolution of taxonomic problems of some groups. In these cases, supplementary chemotaxonomic studies using thin-layer chromatography are carried out.
Characterisation and assessment of the ecological factors influencing the presence and abundance of species per habitat, which will provide a significant information about the ecological and spatial amplitude of each species in the territory (stenotopic and eurytopic species).
Identification and quantification of bioindicator species power per habitat distinguishing, therefore, the most characteristic and sensitive habitats for the growth of these genera.

Because Cladina and Cladonia species are protected by the environmental laws of Luxembourg, the results obtained in this project can represent fundamental arguments in the configuration of adequate protection strategies of these lichen genera as well as their more significant habitats.