| Conesticks | |
|---|---|
| |
| Petrophile sessilis near Bylong | |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Order: | Proteales |
| Family: | Proteaceae |
| Genus: | Petrophile |
| Species: | P. sessilis
|
| Binomial name | |
| Petrophile sessilis | |
| Synonyms[1] | |
| |
Petrophile sessilis, known as conesticks,[2] is a species of flowering plant in the family Proteaceae and is endemic to New South Wales. It is an erect shrub with rigid, needle-shaped, divided, sharply-pointed leaves, and oval, spike-like heads of silky-hairy, creamy-yellow flowers.
Petrophile sessilis is an erect shrub that typically grows to a height of 3 m (9.8 ft) and has branchlets and leaves that are silky-hairy when young but become glabrous with age. The leaves are 30–100 mm (1.2–3.9 in) long and divided with rigid, sharply-pointed, needle-shaped pinnae usually less than 10 mm (0.39 in) long. The flowers are arranged on the ends of branchlets and in leaf axils in spike-like, oval heads 20–25 mm (0.79–0.98 in) long, with broadly egg-shaped involucral bracts at the base. The flowers are 10–14 mm (0.39–0.55 in) long, silky-hairy and creamy-yellow. Flowering mainly occurs from May to February and the fruit is a nut, fused with others in a oval head up to 35 mm (1.4 in) long.[2][3] It can be distinguished from the related Petrophile pulchella by its finely hairy new growth.[4]
Petrophile sessilis was first formally described in 1827 by Josef August Schultes in the 16th edition of Systema Vegetabilium from an unpublished description by Franz Sieber.[5][6]
Petrophile sessilis grows on sandstone soils in heath, woodland and forest from the Central Coast to the Central and Southern Tablelands of New South Wales.[2][3]