Dicrastylis from the Greek 'dicroos' meaning forked and 'stylos' meaning a style; alluding to the deeply 2-branched style. Costelloi name after M. Costello, who collected the type specimen from near Lake Nash on the border between Queensland and Northern Territory.
Distribution and status
Found in far northern of South Australia growing in deep red sand, on sand dunes with spinifex. Also found in Western Australia, Northern Territory and Queensland. Native. Common in South Australia. Common in the other States.
Herbarium regions: North Western, Lake Eyre
NRM regions: Alinytjara Wilurara, South Australian Arid Lands
AVH map: SA distribution map (external link)
Greyish hairy shrub to 90 cm high with erect, woody and branching stems covered in dense hairs. Leaves sessile, opposite or in whorls of 3; linear or linear-lanceolate, obtuse, with recurved-revolute margins, to 3 cm long and 6 mm wide; greyish- hairy when young, the older glabrescent and rugose. Inflorescence terminal, spike-like with a few branches near the base of the spike; hairy and with whitish-grey, purplish-violet or purplish-grey flowers. Flowers sporadically. Fruits are greyish ovoid to globular fruit to 3.3 mm diameter, covered ion short hairs.
Seed collection and propagation
Collect mature fruits that are fat and spongy. May need to collect a lot as most will not have any viable seeds. Place the fruit in a tray and leave to dry for 1 to 2 weeks. Then rub the dried fruits with a rubber bung to dislodge the seeds. Use a sieve to separate any unwanted material. Store the seeds with a desiccant such as dried silica beads or dry rice, in an air tight container in a cool and dry place.