Zamárraga
A species of the Compositae family. It was described by the Swiss botanist Augustin Pyrame de Candolle in 1838, in his seminal work Podromus. The description was made at the request of his friend Edmond Boissier, a French botanist who had travelled through southern Spain in 1837 and collected a significant number of plant specimens. Among them was this interesting species, later included by Candolle in his publication.
Distribution
This species is endemic to the highest elevations of the Sierra Nevada in Granada, where it lives above 3,000 metres, predominantly on north-facing slopes.
Habitat
It grows in high-mountain pastures, between 3000 and 3460 metres above sea level, on the highest peaks of the Sierra Nevada. It is typically found in small patches of soil nestled between large slabs of rock. Although it prefers north-facing exposures, it can occasionally be found in other orientations. Flowering occurs in July and August, and seeds are dispersed by the wind.
Conservation
Approximately 100 individuals have been recorded, widely scattered across two populations. The main population is distributed discontinuously along the 3000 metre elevation axis, spanning the Veleta, Mulhacén and Alcazaba peaks. The species’ primary threat is browsing, as much of the flowering heads are consumed by domestic livestock or mountain goats. Trampling is another significant threat, as it compacts the soil and facilitates the invasion of other species of the same genus, with which our species appears unable to compete. The species is also highly vulnerable to catastrophic events such as droughts, landslides or storms, which can eliminate individuals through desiccation or burial. Conservation efforts have included reinforcement of populations through high-mountain conservation programmes and initiatives by the Network of Botanical Gardens of the Andalucía Regional Government (Junta de Andalucía). Seeds are preserved in the Andalucía Plant Germplasm Bank, and laboratory test have shown that seed germination in the laboratory presents no difficulties. It has been recommended to reduce the presence of ibex and livestock and to intensify both population reinforcement and monitoring.
Image description
The optical microscope image shows the body and the pappus of two achenes (fruits). The pappus consists of a tuft of hairs of uniform length, whitish in colour, and very finely toothed. The achene body is elongated and narrow, approximately two millimetres long, featuring lateral ribs lined with short, stiff hairs.
The scanning electron microscope image shows a close-up of the achene surface, revealing the tips of the epidermal scales that cover it.
Visual touch photography
The electron microscope image shows a detail of the surface of the body of an achene (fruit). It is elongated and narrow, approximately two millimetres long, and features lateral ribs bearing both short and long hairs. The image highlights the surface structure, including the tips of the epidermal scales that cover it.