''Allocasuarina anfractuosa'', commonly known as sinuous sheoak, is a species of flowering plant in the family

Casuarinaceae The Casuarinaceae are a family of dicotyledonous flowering plants placed in the order Fagales, consisting of four genera and 91 species of trees and shrubs native to eastern Africa, Australia, Southeast Asia, Malesia, Papuasia, and the Pacific ...

and is endemic to a restricted area in the

southwest The points of the compass are a set of horizontal, radially arrayed compass directions (or azimuths) used in navigation and cartography. A '' compass rose'' is primarily composed of four cardinal directions—north, east, south, and west— ...

of Western Australia. It is a bushy,

monoecious Monoecy (; adj. monoecious ) is a sexual system in seed plants where separate male and female cones or flowers are present on the same plant. It is a monomorphic sexual system comparable with gynomonoecy, andromonoecy and trimonoecy, and contras ...

shrub that has spreading, sinuous branchlets, the leaves reduced to scales in whorls of 11 to 15, the fruiting cones long containing winged seeds (samaras) long.

Description

''Allocasuarina anfractuosa'' is a bushy, monoecious shrub that typically grows to a height of up to about . Its branchlets are spreading, up to long and sinuous, the leaves reduced to erect or spreading, scale-like teeth long, arranged in whorls of 11 to 15 around the branchlets. The sections of branchlet between the leaf whorls (the "articles") are long and wide. Male flowers are arranged in head-like spikes long on the ends of branchlets, the

anthers The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filamen ...

long. Female cones are covered with fine, white or dark yellowish hairs when young, and are

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

or on a peduncle up to long. Flowering has been observed in August and mature cones are more or less cylindrical, long and in diameter, the samaras dark brown and long.

Taxonomy

''Allocasuarina anfractuosa'' was first formally described in 2016 by

Juliet Wege Juliet Ann Wege (born 1971 in Western Australia) is an Australian botanist. She graduated in 1992 and gained a PhD at The University of Western Australia in 1999 with a thesis titled "Morphological and anatomical variation within Stylidium (Stylid ...

and Sarah Barrett in the journal ''

Nuytsia ''Nuytsia floribunda'' is a hemiparasitic tree found in Western Australia. The species is known locally as moodjar and, more recently, the Christmas tree or Western Australian Christmas tree. The display of intensely bright flowers during the ...

'' from specimens collected by Barrett near the

Pallinup River The Pallinup River is a river located in the Great Southern region of Western Australia. It was previously known as Salt River. The Pallinup rises 10 km southeast of Broomehill, and flows in a southeasterly direction toward the coast pas ...

in 2014. The specific epithet, (''anfractuosa'') means "sinuous", referring to the branchlets.

Distribution and habitat

Sinuous sheoak grows in heath where it often forms dense stands, and is only known from a small area north-west of

Boxwood Hill Boxwood Hill is a town and locality in the Shire of Jerramungup, Great Southern region of Western Australia. Boxwood Hill is situated at the intersection of the South Coast Highway and the Borden-Bremer Bay Road. The Pallinup River forms the l ...

in the

Esperance Plains Esperance Plains, also known as Eyre Botanical District, is a biogeography, biogeographic region in southern Western Australia on the South_coast_of_Western_Australia , south coast between the Avon Wheatbelt and Hampton bioregions, and bordere ...

bioregion of south-western Western Australia.

Conservation status

''Allocasuarina anfractuosa'' is listed as " Priority One" by the Government of Western Australia

Department of Biodiversity, Conservation and Attractions The Department of Biodiversity, Conservation and Attractions (DBCA) is the Government of Western Australia, Western Australian government department responsible for managing lands and waters described in the ''Conservation and Land Management A ...

, meaning that it is known from only one or a few locations that are potentially at risk.

References

{{Taxonbar, from=Q51046069 anfractuosa Rosids of Western Australia Fagales of Australia Plants described in 2016