In the Monchique mountains, where the slopes are composed of rare nepheline syenite, a tiny plant hides among low grasses and shrubs, remaining unknown to science until recently. A German tourist simply took a photo with her phone and uploaded it to the iNaturalist platform — and this chance photograph set off a chain of research that culminated in the description of a new endemic species of the Algarve.
The plant was named Linaria alfercensis, or in Portuguese ansarina-de-alferce. It is a small annual toadflax with yellow flowers adorned with orange-brown markings. Flowering occurs from March to May, and its range is limited to the southern slopes of the Serra da Picota in the municipality of Monchique, especially the surroundings of Cerro do Castelo de Alferce. Scientists led by João Farminhão of the University of Coimbra confirmed its distinctness using morphological, genomic and ecological data, publishing the results in the journal Plant Ecology and Evolution.
The discovery highlights how closely the plant diversity of the Algarve is tied to geology. Rare rocks create distinctive "soil islands" where isolated populations evolve independently. The same work confirmed the status of another local endemic — Linaria bimaculata. However, even now Linaria alfercensis faces serious threats: habitat loss, the spread of invasive mimosa (Acacia dealbata) and the pressure of tourist development.
The researchers propose classifying the species as "endangered" according to IUCN criteria. The populations are small and the range extremely narrow — factors that make the plant vulnerable even before its formal description. As Farminhão notes, Portugal remains a "blank spot" in the knowledge of its flora, and some species may disappear before they can be studied.
The case of Linaria alfercensis shows the role played by citizen science: a single photograph uploaded by a vacationer drew the attention of botanists and led to an expedition.
The conservation of such narrowly local endemics begins with attention to every patch of rare soil and the control of invasive species in key locations.
