-Senecio coincyi (Asteraceae) is a threatened endemic plant of central western Spain. The reproductive biology of this species in relation to the characteristics of its habitats and the possible strategies for its conservation, were studied. The area of occupancy, habitat types and size of 13 known subpopulations of S. coincyi was evaluated. Germination tests were carried out to assess the effect of temperature and light regimes, and the possible intraspecific variation on the cypsela germination. Cypselas reached very high germination percentages (90-100%) from 15°C to 30°C. However, the germination decreased (by about 19%) at 10°C. The light conditions assayed did not significantly affect cypsela germination. In conclusion, S. coincyi showed high sexual reproduction ability, and therefore its conservation problems are not due to agents related to its reproductive biology, but to others, such as the alteration of its habitat caused by the presence of livestock.