Kingdom Plantae Family Lamiaceae Rank Species | Order Lamiales Genus Prostanthera | |
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Similar Prostanthera cryptandroides, Prostanthera walteri, Prostanthera linearis, Prostanthera striatiflora, Prostanthera denticulata | ||
Prostanthera stenophylla is a shrub species that is endemic to Wollemi National Park in New South Wales, Australia. It grows to between 1.5 and 2 metres (4.9 and 6.6 ft) high and has leaves that are 7 to 12 millimetres (0.28 to 0.47 in) long and 1.5 to 2 millimetres (0.059 to 0.079 in) wide. Dull green above and paler green below, leaves are covered with a dense mat of hairs and give off a strong aroma when crushed. The leaf edges are recurved or revolute. Mauve or violet flowers appear in the leaf axils in spring, with about 4 to 6 flower-bearing branchlets arising on a leafy branch to form a raceme. Individual flowers are about 8 to 12 millimetres (0.31 to 0.47 in) long.
The species was first formally described by Barry Conn of the New South Wales Herbarium in the journal Telopea in 2006. He held it to be allied to the granite mintbush (Prostanthera granitica), within the genus. The latter species is similar in appearance but has stiffer rougher hairs and broader leaves.
Prostanthera stenophylla is found in sclerophyll forest dominated by black cypress pine (Callitris endlicheri), snappy gum (Eucalyptus rossii) and Sydney peppermint (E. piperita), where it arises in sandstone outcrops, which are colloquially known as 'pagodas'.
The first recorded collection of plant material from the type locality was by nurseryman George Althofer in 1952. A 1937 collection by Lindsay Pryor is recognised as this species, but the given locality of "Canberra district" is believed to be incorrect. The specific epithet stenophylla is a combination of the Greek words steno (narrow) and phylla (leaves).
The species has been in limited cultivation for some years. The unofficial name of Prostanthera rylstonii has been used by plant nurseries since at least 2005.