Leontodon filii

Leontodon filii is a perennial herb with an oblique, truncate stock. Its stems range in height from 20 to 50 cm and are typically branched, bearing numerous rigid, simple, eglandular, and long-stalked 2- to 3-fid hairs. The plant usually has 0–3 bracts. The leaves are elliptical to oblanceolate, measuring 30–170 mm in length and 15–45 mm in width. They are obtuse to subacute at the apex and long-attenuate at the base, forming a winged petiole. The margins are dentate with narrow, patent teeth. The leaves are also covered in numerous rigid, simple, eglandular, or long-stalked 2-fid hairs. The plant produces 1–4 capitula on long peduncles. The involucre is 10–13 mm in length and 7–10 mm in width, with linear bracts that are more or less obtuse and either glabrous or sparsely to densely covered with simple, eglandular, or long-stalked 2-fid hairs. The ligules are yellow, and the stigmas are yellow or discoloured. The achenes are 4.5–5.5 mm in length, pale brown, weakly transversely muricate, and shortly beaked. The pappus consists of two rows of hairs, with the inner row plumose and the outer row scabrid.

Leontodon filii is native to the Azores, where it is found on several islands including Faial, Pico, São Jorge, São Miguel, and Terceira. It typically inhabits rocky or disturbed areas, such as cliffs, scree slopes, and other open, well-drained sites. These habitats are often characterized by low nutrient levels and exposure to wind, which the plant has adapted to through its rigid hairs and compact growth form.

Cultivating Leontodon filii requires conditions that mimic its natural habitat. It thrives in well-drained, rocky soils and prefers full sun to partial shade. The plant is drought-tolerant and does not require frequent watering. It is best suited for rock gardens or alpine gardens where it can receive good air circulation. Propagation can be done through seeds or division of the rootstock. Due to its specific ecological requirements, it may be challenging to grow outside of its native range without careful attention to soil composition and drainage.

Leontodon filii is primarily of interest to botanists and horticulturists due to its endemic status in the Azores. It is not widely cultivated for ornamental or medicinal purposes. However, its unique morphology and ecological adaptations make it a valuable subject for botanical research, particularly in the study of island endemism and plant adaptation to harsh environments. Conservation efforts are important to preserve its natural populations, as it is a rare and localized species within its range.