''Thomasia × formosa'' is a species of flowering plant in the family

Malvaceae Malvaceae, or the mallows, is a family of flowering plants estimated to contain 244 genera with 4225 known species. Well-known members of economic importance include okra, cotton, cacao and durian. There are also some genera containing familiar o ...

and is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

to a restricted area of the south-west of Western Australia. It is an erect, compact shrub with densely hairy branchlets, hairy, coarsely serrated, egg-shaped to elliptic or oblong leaves, and

raceme A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the sh ...

s of pink or purple flowers arranged in leaf axils.

Description

''Thomasia × formosa'' is an erect, compact shrub that typically grows to high, wide and has its branchlets densely covered with rust-coloured, star-shaped hairs. The leaves are egg-shaped to elliptic or oblong, long and wide, tapering to a petiole long with oval

stipule In botany, a stipule is an outgrowth typically borne on both sides (sometimes on just one side) of the base of a leafstalk (the petiole). Stipules are considered part of the anatomy of the leaf of a typical flowering plant, although in many speci ...

s long at the base. The upper surface of the leaves is wrinkled, the edges have rounded teeth and down-curved edges, and both surfaces are covered with rust-coloured, star-shaped hairs. The flowers are arranged in

s of 7 or more in leaf axils on a

peduncle Peduncle may refer to: *Peduncle (botany), a stalk supporting an inflorescence, which is the part of the shoot of seed plants where flowers are formed *Peduncle (anatomy), a stem, through which a mass of tissue is attached to a body **Peduncle (art ...

long, each flower on a

pedicel Pedicle or pedicel may refer to: Human anatomy *Pedicle of vertebral arch, the segment between the transverse process and the vertebral body, and is often used as a radiographic marker and entry point in vertebroplasty and kyphoplasty procedures ...

up to long, with egg-shaped bracts and 3 bracteoles about long at the base. The

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined ...

s are pink or purple with lobes long. Flowering occurs in September and October.

Taxonomy and naming

''Thomasia × formosa'' was first formally described in 1974 by Susan Paust 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 b
Charles Chapman
near Three Springs in 1972. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

(''formosa'') means "handsome". This species is an inter-generic

hybrid Hybrid may refer to: Science * Hybrid (biology), an offspring resulting from cross-breeding ** Hybrid grape, grape varieties produced by cross-breeding two ''Vitis'' species ** Hybridity, the property of a hybrid plant which is a union of two diff ...

between '' Thomasia macrocalyx'' and '' Lysiosepalum rugosum''.

Distribution and habitat

This thomasia grows in mallee woodland, shrubland and heath in a restricted area near Three Springs in the

Avon Wheatbelt The Avon Wheatbelt is a bioregion in Western Australia. It has an area of . It is considered part of the larger Southwest Australia savanna ecoregion. Geography The Avon Wheatbelt bioregion is mostly a gently undulating landscape with low reli ...

and

Geraldton Sandplains Geraldton ( Wajarri: ''Jambinu'', Wilunyu: ''Jambinbirri'') is a coastal city in the Mid West region of the Australian state of Western Australia, north of the state capital, Perth. At June 2018, Geraldton had an urban population of 37,648. ...

bioregions of south-western Western Australia.

Conservation status

''Thomasia × formosa'' is listed as "

Threatened Threatened species are any species (including animals, plants and fungi) which are vulnerable to endangerment in the near future. Species that are threatened are sometimes characterised by the population dynamics measure of ''critical depensa ...

" by the Western Australian Government

Department of Biodiversity, Conservation and Attractions The Department of Biodiversity, Conservation and Attractions (DBCA) is the Western Australian government department responsible for managing lands and waters described in the ''Conservation and Land Management Act 1984'', the ''Rottnest Island ...

, meaning that it is in danger of extinction.

References

Rosids of Western Australia Plants described in 1974 x formosa {{DEFAULTSORT:Thomasia x formosa