Allocasuarina pusilla

Summary

Allocasuarina pusilla, commonly known as heath oak-bush[2] or dwarf sheoak,[3] is a species of flowering plant in the family Casuarinaceae and is endemic to south-eastern continental Australia. It is a spreading, dioecious shrub with branchlets up to 120 mm (4.7 in) long, the leaves reduced to scales in whorls of five to seven, the fruiting cones 10–15 mm (0.39–0.59 in) long containing winged seeds about 5 mm (0.20 in) long.

Allocasuarina pusilla
In Wyperfeld National Park
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Fagales
Family: Casuarinaceae
Genus: Allocasuarina
Species:
A. pusilla
Binomial name
Allocasuarina pusilla
Occurrence data from AVH

Description edit

Allocasuarina pusilla is a spreading, dioecious shrub that typically grows to a height of 0.2–2 m (7.9 in – 6 ft 6.7 in) and has smooth bark. Its branchlets are erect to spreading, up to 120 mm (4.7 in) long, the leaves reduced to overlapping, scale-like teeth 0.3–0.5 mm (0.012–0.020 in) long, arranged in whorls of five to seven around the branchlets. The sections of branchlet between the leaf whorls are 3–9 mm (0.12–0.35 in) long and 0.4–1 mm (0.016–0.039 in) wide. Male flowers are arranged in spikes 3–20 mm (0.12–0.79 in) long, with about 8 to 11 whorls per centimetre (per 0.39 in.), the anthers 0.6–1 mm (0.024–0.039 in) long. Female cones are sessile, the mature cones shortly cylindrical to more or less spherical, 10–15 mm (0.39–0.59 in) long and 8–11 mm (0.31–0.43 in) in diameter, the winged seeds dark brown to black and about 5 mm (0.20 in) long.[2][3][4]

Taxonomy edit

This sheoak was first formally described in 1927 by Ellen Dulcie Macklin who gave it the name Casuarina pusilla in the Transactions and Proceedings of the Royal Society of South Australia.[5][6] It was reclassified in 1982 as Allocasuarina pusilla by Lawrie Johnson in the Journal of the Adelaide Botanic Gardens.[7] The specific epithet (pusilla) means "very small",[8] possibly referring to the habit of the plant.[2]

Distribution and habitat edit

Allocasuarina pusilla grows in heath on sandy soils from the Yorke Peninsula in south-eastern South Australia to the Big and Little Deserts of western Victoria in the south-east of continental Australia.[2][3][4]

References edit

  1. ^ "Allocasuarina pusilla". Australian Plant Census. Retrieved 4 August 2023.
  2. ^ a b c d "Allocasuarina pusilla (Casuarinaceae)". South Australian Seed Conservation Service. Retrieved 4 August 2023.
  3. ^ a b c Entwisle, Timothy J.; Stajsic, Val. "Allocasuarina pusilla". Royal Botanic Gardens Victoria. Retrieved 4 August 2023.
  4. ^ a b "Allocasuarina pusilla". Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra. Retrieved 4 August 2023.
  5. ^ "Casuarina pusilla". APNI. Retrieved 4 August 2023.
  6. ^ Macklin, Ellen D. (1927). "A Revision of the "Distyla Complex" of the Genus Casuarina". Transactions and Proceedings of the Royal Society of South Australia. 51: 272–274. Retrieved 4 August 2023.
  7. ^ "Allocasuarina pusilla". APNI. Retrieved 4 August 2023.
  8. ^ Sharr, Francis Aubi; George, Alex (2019). Western Australian Plant Names and Their Meanings (3rd ed.). Kardinya, WA: Four Gables Press. p. 287. ISBN 9780958034180.

External links edit