Acacia atrox, commonly known as Myall Creek wattle, is a species of flowering plant in the family Fabaceae, endemic to a restricted region of New South Wales, Australia. It is classified as Critically Endangered under the NSW Biodiversity Conservation Act 2016.
Taxonomy
- Kingdom: Plantae
- Clade: Angiosperms → Eudicots → Rosids → Mimosoid clade
- Order: Fabales
- Family: Fabaceae (legume family)
- Subfamily: Caesalpinioideae
- Genus: Acacia
- Species: A. atrox Kodela, 2001
Two subspecies are recognised: the autonym A. atrox subsp. atrox and A. atrox subsp. planiticola. Synonyms include Racosperma atrox (Pedley) and an invalidly published name Acacia atrox Kodela.
Description
Acacia atrox is a dense, small shrub or tree, typically 2–4 m tall, often forming suckers that create multi‑branched thickets. Its phyllodes are sessile, terete (cylindrical) to four‑angled, 15–50 mm long and 0.7–1.5 mm wide, bearing four to eight longitudinal veins and terminating in a sharply pointed tip.
Inflorescences are spherical heads of 17–41 cream‑to‑pale yellow flowers, arranged in racemes on peduncles 5–32 mm long; each head measures 5–11 mm across. Flowering has been recorded from March to July (most commonly May and July). Fruit and seeds have not yet been documented.
Distribution and Habitat
The species is known only from a small area of the north‑western slopes of New South Wales, particularly around Myall Creek Station near Delungra and the Inverell region. Populations occupy less than 5 ha in total, occurring on sandy or loamy soils within open woodland communities. Two separate populations are recorded: one near Delungra and another near Gurley.
Conservation Status
Acacia atrox is listed as Critically Endangered under the New South Wales Biodiversity Conservation Act 2016. Threats include habitat loss due to agricultural expansion, grazing pressure, altered fire regimes, and potential impacts of climate change. Limited distribution and small population size heighten its vulnerability.
Subspecies
- A. atrox subsp. atrox (autonym): phyllodes with bases 2–6 mm long; flower heads contain 17–41 flowers; flowering recorded in May and July.
- A. atrox subsp. planiticola: phyllode bases 1.0–2.2 mm long; flower heads contain 17–25 flowers; flowering observed in April and May. The epithet “planiticola” means “plains‑dweller”.
Etymology
The specific epithet atrox derives from Latin, meaning “cruel, fierce, harsh, horrible, savage, or terrible”, a reference to the plant’s sharply pointed foliage.
References
Information summarized from the Wikipedia entry on Acacia atrox (accessed via r.jina.ai), which compiles data from primary botanical sources such as the journal Telopea, the Australian Plant Census, and the Australasian Virtual Herbarium.