Cyanothamnus quadrangulus, commonly known as narrow-leaved boronia,[2] is a plant in the citrus family, Rutaceae and is endemic to eastern Australia. It is an erect shrub with four-angled branches, bipinnate leaves and white, sometimes pale pink, four-petalled flowers.
Description
Cyanothamnus quadrangulus is an erect shrub that grows to a height of 0.3–1 m (1–3 ft) with four-angled, glabrous stems with prominent leaf scars. The leaves are bipinnate, 20–40 mm (0.79–1.6 in) long and 15–40 mm (0.59–1.6 in) wide in outline and have a petiole 6–15 mm (0.24–0.59 in) long. The leaves have between five and eleven glabrous, linear to narrow elliptic leaflets. The end leaflet is 3–14 mm (0.1–0.6 in) long and 0.5–2 mm (0.02–0.08 in) wide, the others usually slightly longer. The flowers are white, sometimes pale pink and are arranged in leaf axils, mainly in groups of between three and fourteen or more. The groups are borne on a peduncle 2–6 mm (0.08–0.2 in) long. The four sepals are triangular to broadly egg-shaped, about 1 mm (0.04 in) long and wide. The four petals are 3–4 mm (0.1–0.2 in) long with their bases overlapping. The eight stamens have hairy edges. Flowering occurs from April to October and the fruit are glabrous, 2.5–4 mm (0.098–0.16 in) long and about 2 mm (0.079 in) wide.[2][3]
In a 2013 paper in the journal Taxon, Marco Duretto and others moved this species to the genus Cyanothamnus on the basis of cladistic analysis, but because the name Cyanothamnus anethifolia had already been used for a different taxon (Cyanothamnus anethifolius Bartl.) the name Cyanothamnus quadrangulus was used.[5] The specific epithet (anethifolia) referred to the deeply divided leaves with narrow leaflets which resemble those of dill (Anethum) in the familyApiaceae[2] and the new epithet (quadrangulus) means "four-angled" and refers to the four-sided stems of this species.[5]
^ abDuretto, Marco F.; Heslewood, Margaret M.; Bayly, Michael J. (2020). "Boronia (Rutaceae) is polyphyletic: Reinstating Cyanothamnus and the problems associated with inappropriately defined outgroups". Taxon. 69 (3): 481–499. doi:10.1002/tax.12242.