1. Floristic investigation of the phonolithic “Roque de los Pinos” in the NE of Tenerife Hildebrandt, Ina 1, Miguel Antonio Padrón Mederos 2, Irma Rosana Guma 2, Jorge Alfredo Reyes-Betancort 2 & Arnoldo Santos Guerra 2 1 Humboldt-Universität zu Berlin, Institut für Biologie, AG Botanik und Arboretum, Invalidenstr. 42, D-10115 Berlin, Germany. Email: ina.hildebrandt@gmx.net 2 Unidad de Botánica Aplicada, Instituto Canario de Investigaciones Agrarias. Jardín de la Aclimatación de La Orotava. C/ Retama nº 2, 38400 Puerto de la Cruz, Tenerife, Canary Islands, Spain Introduction A preliminary study on the vascular flora of the phonolitic “Roque de los Pinos” (height 560 m) in the Anaga massif (NE of Tenerife, Canary Islands) has been conducted with the aim to obtain a detailed knowledge of endemism in this geographically isolated formation. Climatic data taken from the meteorological station in Las Carboneras provides a Subhumid Oceanic- pluviseasonal Thermomediterranean (with trade-wind clouds) bioclimatical belt with a mean annual temperature of 16.2 C° and annual rainfall of 696.9 mm (Del-Arco et al. 2006) for the studied area. Fig. 6. Cistus chinamadensis ssp. chinamadensis Fig. 1. Percentage of endemic taxa in the “Roque de los Pinos”. Fig. 7. Convolvulus floridus Fig. 5. Carlina salicifolia ssp. salicifolia Acknowledgement This study was carried out with the financial support by the Leonardo da Vinci program (Germany). Results and Discussion  The vascular flora of the studied areas of the “Roque de los Pinos” contains 121 taxa (Tab.1).  The data provide a high percentage of endemism (Fig. 1). About 70% of the identified taxa include endemics to the Macaronesian Archipelagos (e.g. Carlina salicifolia ssp. salicifolia, Hypericum canariense, Ilex canariensis), to the Canary Islands (e.g. Micromeria varia ssp. varia, Paronychia canariensis, Pinus canariensis), to Tenerife (e.g. Aeonium canariense var. canariense and Lavandula canariensis ssp. canariensis) and local endemics like Cistus chinamadensis ssp. chinamadensis.  The cartographic map (north to south) of the founded phytosociologic units (Fig. 2) shows that the growth of the thermophilous woodland is limited because of the poor soil conditions in upper zones. Thus, the colonization by Pinus canariensis can be explained by the presence of the salic substratum in the top of the “Roque de los Pinos”.  The distribution maps of some selected species (Fig. 3 and Fig. 4) show that the north and south face of the “Roque” can be clearly distinguished because of its floristical composition.  Further investigations on population genetics and morphology are needed in order to develop strategies for the conservation of endemic species identified in this study (e. g. Fig. 5, 6, 7). Fig. 2. Cartographic map of the phytosociologic units (north and south face of the studied area). References Del-Arco, M., Pérez-de-Paz, P. L., Acebes, J. R., González-Mancebo, J. M., Reyes- Betancort, J. A., Bermejo, J. A., De-Armas, S. & González-González, R. 2006. Bioclimatology and climatophilous vegetation of Tenerife (Canary Islands). Annales Botanici Fennici 43: 167–192 Fig. 4. Distribution map of Cheirolophus anagensis (green) and Pterocephalus virens (darkblue). The maximum height is marked (x). x N Fig. 3. Distribution map of Teline pallida ssp. silensis (red) and Ruta pinnata (blue). The maximum height is marked (x). x N Tab. 1. List of the vascular flora of the studied area.