Asterolasia asteriscophora

Asterolasia asteriscophora, commonly known as lemon starbush,^[2] is a species of slender, erect shrub in the family Rutaceae and is endemic to southern continental Australia. It has woolly, star-shaped hairs on its young branches, variably-shaped leaves covered with brownish or whitish hairs on the underside, and yellow flowers with brown, star-shaped hairs on the back.

Lemon starbush
Subspecies asteriscophora
Subspecies albiflora in Emerald
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Sapindales
Family:	Rutaceae
Genus:	Asterolasia
Species:	A. asteriscophora
Binomial name
Asterolasia asteriscophora (F.Muell.) Druce[1]
Synonyms[1]
Asterolasia correifolia var. muelleri Maiden & Betche Asterolasia muelleri Benth. nom. illeg. Phebalium asteriscophorum F.Muell.

Description

Asterolasia asteriscophora is a slender, erect shrub that typically grows to a height of 1–2 m (3 ft 3 in – 6 ft 7 in) with its young branches covered with woolly, grey to brown star-shaped hairs. The leaves are spatula-shaped, egg-shaped, wedge-shaped or elliptic, 3–30 mm (0.12–1.18 in) long and 2–10 mm (0.079–0.394 in) wide on a short petiole. The upper surface of the leaves is more or less glabrous and the lower surface is covered with woolly, brownish or whitish hairs. The flowers are arranged singly or in small groups in leaf axils or on the ends of branchlets on pedicels 2–20 mm (0.079–0.787 in) long. The petals are yellow, rarely white, 5–7 mm (0.20–0.28 in) long and covered with brown, woolly, star-shaped hairs on the back. Flowering occurs in spring.^{[2][3][4][5][6]}

Taxonomy

This species was first described in 1855 by Ferdinand von Mueller who gave it the name Phebalium asteriscophora and published the description in Transactions and Proceedings of the Victorian Institute for the Advancement of Science.^[7][8] In 1917 George Claridge Druce changed the name to Asterolasia asteriscophora.^[9][10]

In 2002, Bryan J. Mole described two subspecies and the names have been accepted by the Australian Plant Census:

• Asterolasia asteriscophora subsp. albiflora^[11] that has white, rarely pale lemon-coloured petals with smaller leaves and flowers that the autonym;
• Asterolasia asteriscophora subsp. asteriscophora^[12] that has bright yellow petals up to 6 mm (0.24 in) long and leaves mostly longer than 12 mm (0.47 in).^[6]

Distribution and habitat

Asterolasia asteriscophora is widely distributed along the Great Dividing Range from the Tumut district in New South Wales to the Macedon and Emerald districts in Victoria. It grows in forest and along the eges of watercourses.^[6] Subspecies albiflora is only known from the Emerald-Avonsleigh and is threatened by urban development.^[6]