Prostanthera arapilensis

Prostanthera arapilensis is an erect, aromatic shrub that typically grows to a height of 0.5–1.5 m (1 ft 8 in–4 ft 11 in) with hairy branches that have spines 6–15 mm (0.24–0.59 in) long arranged in opposite pairs at right angles to each other. The leaves are light to dark green, paler on the lower surface, egg-shaped to more or less round, 30–45 mm (1.2–1.8 in) long and 1–2 mm (0.039–0.079 in) wide on a petiole up to 1 mm (0.039 in) long. The leaves are hairy with oil glands on the lower surface. The flowers are arranged in leaf axils with bracteoles 1.5–2 mm (0.059–0.079 in) long and 0.2–0.3 mm (0.0079–0.0118 in) wide. The sepals are 5.5–7 mm (0.22–0.28 in) long, joined at the base forming a tube 3–4 mm (0.12–0.16 in) long with two lobes, the upper lobe 1.5–3 mm (0.059–0.118 in) long. The petals are 12–19 mm (0.47–0.75 in) long, pale mauve or white with orange-brown spots or streaks inside the petal tube.[2]

Prostanthera arapilensis was first formally described in 2006 by Mark Williams, Andrew Drinnan and Neville Walsh in the journal Australian Systematic Botany from specimens collected on Mount Arapiles.[3][4]

This mintbush grows in heathy woodland and scrubland and is only known from the rocky summit of Mount Arapiles.[2]