''Thomasia dielsii'' 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 ...

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 elsew ...

to the

south-west 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—each se ...

of Western Australia. It is a low, erect to spreading shrub with egg-shaped leaves with wavy edges, and purple, violet and blue flowers.

Description

''Thomasia dielsii'' is an erect to spreading shrub that typically grows to high, wide and has its young stems covered in greyish, star-shaped. The leaves are egg-shaped to oblong, long and wide on a petiole long. The edges of the leaves are wavy and slightly serrated, the upper surface with a few star-shaped hairs, the lower surface more densely hairy. There are hairy, smaller leaf-like

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 at the base of the petioles. The flowers are arranged in

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 s ...

s of 4 to 9, each flower on a hairy

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 ...

long, with hairy, linear

bracteoles In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or of ...

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 b ...

s are purple, violet and blue, long, and there are no petals, the

style Style is a manner of doing or presenting things and may refer to: * Architectural style, the features that make a building or structure historically identifiable * Design, the process of creating something * Fashion, a prevailing mode of clothing ...

protruding above the

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filame ...

Taxonomy and naming

''Thomasia dielsii'' was first formally described in 1904 by

Ernst Georg Pritzel Ernst Georg Pritzel (15 May 1875 – 6 April 1946) was a German botanist. He is known for his research in the fields of phytogeography and taxonomy. He contributed works on Lycopodiaceae, Psilotaceae and Pittosporaceae to Engler & Prantl’s "Die ...

in ''

Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie This is a list of academic journals, monographic series, and other serials published by E. Schweizerbart. A B C D E F G H I J K L M N P Q R S T U V W Z {{columns-list, colwidth=30em, *''Zeitschrift d ...

'' from specimens he collected near Cranbrook. 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 ...

(''dielsii'') honours

Ludwig Diels Dr. Friedrich Ludwig Emil Diels (24 September 1874 – 30 November 1945) was a German botanist. Diels was born in Hamburg, the son of the classical scholar Hermann Alexander Diels. From 1900 to 1902 he traveled together with Ernst Georg Prit ...

Distribution and habitat

This thomasia grows on flats from near Cranbrook to

Israelite Bay Israelite Bay is a bay and locality on the south coast of Western Australia. Situated in the Shire of Esperance local government area, it lies east of Esperance and the Cape Arid National Park, within the Nuytsland Nature Reserve and the Grea ...

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 ...

Esperance Plains Esperance Plains, also known as Eyre Botanical District, is a biogeographic region in southern Western Australia on the south coast between the Avon Wheatbelt and Hampton bioregions, and bordered to the north by the Mallee region. It is a pl ...

and

Jarrah Forest Jarrah forest is tall open forest in which the dominant overstory tree is ''Eucalyptus marginata'' (jarrah). The ecosystem occurs only in the Southwest Botanical Province of Western Australia. It is most common in the biogeographic region named in ...

bioregions of south-western Western Australia.

Conservation status

''Thomasia dielsii'' is classified as "

Priority One Prioritization is an action that arranges items or activities in order of importance. Priority may refer specifically to: Law * Priority or right of way on the road, see Traffic § Priority (right of way) ** Priority signs, a traffic sign that ...

" by the Government of Western Australia

Department of Biodiversity, Conservation and Attractions The Department of Biodiversity, Conservation and Attractions (DBCA) is the Western Australian government The Government of Western Australia, formally referred to as His Majesty's Government of Western Australia, is the Australian state de ...

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

References

{{Taxonbar, from=Q17580971 Rosids of Western Australia Plants described in 1904 dielsii Taxa named by Ernst Pritzel