Allocasuarina ramosissima is a species of flowering plant in the family Casuarinaceae and is endemic to the south-west of Western Australia. It is a dioecious shrub with its leaves reduced to overlapping scales in whorls of five, the mature fruiting cones sessile and long, containing winged seeds long.
Allocasuarina ramosissima is a dioecious, somewhat divaricate shrub that typically grows to a height of . Its branchlets are erect long, the leaves reduced to overlapping scale-like teeth long, arranged in whorls of five around the needle-like branchlets. The sections of branchlet between the leaf whorls are mostly long and wide. Male flowers are arranged in spike-like heads long, the anthers long. Female cones are sessile, the mature cones long and in diameter, containing dark brown winged seeds long.[1]
This sheoak was first formally described in 1964 by Charles Gardner who gave it the name Casuarina ramosissima in the Journal of the Royal Society of Western Australia from specimens he collected near Dandaragan.[2] [3] It was reclassified in 1982 as Allocasuarina ramosissima by Lawrie Johnson in the Journal of the Adelaide Botanic Gardens.[4] The specific epithet (ramosissima) means "much branched".[5]
Allocasuarina ramosissima grows in heath on sand in the Badgingarra – Dandaragan area in the Avon Wheatbelt, Geraldton Sandplains, Jarrah Forest and Swan Coastal Plain bioregions of south-western Western Australia.