About Boronia filifolia F.Muell.
Boronia filifolia F.Muell. is a slender, hairless shrub that reaches around 50 cm (20 inches) in height. Its leaves are either simple or trifoliate, growing on a leaf stalk (petiole) 2–8 mm (0.08–0.3 inches) long. Simple leaves are linear to narrow egg-shaped, measuring 3–30 mm (0.1–1 inch) long and 1–1.5 mm (0.04–0.06 inches) wide. The three leaflets of trifoliate leaves are similar to each other in shape, 3–10 mm (0.1–0.4 inches) long and 1–1.5 mm (0.04–0.06 inches) wide. Flowers of this species range from pale to deep pink, and are most often arranged singly in leaf axils near the ends of branches, on a flower stalk (pedicel) 2–13 mm (0.08–0.5 inches) long. It has four sepals that are triangular to egg-shaped, 1–3 mm (0.04–0.1 inches) long and 0.5–1.5 mm (0.02–0.06 inches) wide, with overlapping bases. The four petals are 4–12 mm (0.2–0.5 inches) long and 1.2–3 mm (0.05–0.1 inches) wide, also overlapping at their bases. The stamens are covered in glandular hairs. Flowering takes place from July to February. This species, commonly called slender boronia, grows in heath, mallee, and woodland habitats. In South Australia, it occurs on the Eyre and Fleurieu Peninsulas and is common on Kangaroo Island. It is rare in Victoria, where it is only recorded in Little Desert National Park, a portion of the Big Desert near the South Australian border, and has a separated disjunct population near Portland.