''Hydrocotyle phoenix'' is a species of annual pennywort and is commonly called fire pennywort. It is only known to grow in south-west Australia, specifically in fire prone habitats; it is unique in this regard as it is the only species of ''Hydrocotyle'' known to have a fire adapted life-history. The specific epiphet "phoenix" references this fire adapted life history as in Greek mythology, a

phoenix Phoenix most often refers to: * Phoenix (mythology), a legendary bird from ancient Greek folklore * Phoenix, Arizona, a city in the United States Phoenix may also refer to: Mythology Greek mythological figures * Phoenix (son of Amyntor), a ...

experiences rebirth by rising from ashes, much like how this plant rises from the ashes after a wildfire.

Description

''Hydrocotyle phoenix'' is a low growing annual herb which grows tall and up to wide with a sprawling habit. The leaves grow from a

basal rosette In botany, a rosette is a circular arrangement of leaves or of structures resembling leaves. In flowering plants, rosettes usually sit near the soil. Their structure is an example of a modified stem in which the internode gaps between the lea ...

. The leaves are

palmate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...

ly lobed and 5-20 mm long by 7-26 mm wide and covered in small hairs. The flowers are borne in a compact

umbel In botany, an umbel is an inflorescence that consists of a number of short flower stalks (called pedicels) that spread from a common point, somewhat like umbrella ribs. The word was coined in botanical usage in the 1590s, from Latin ''umbella'' "p ...

with about 10-20 flowers. The flowers themselves are small, only 4-6 mm wide, and white. The flowers have only 5 white petals and lack a calyx. The fruits are

schizocarp A schizocarp is a dry fruit that, when mature, splits up into mericarps. There are different definitions: * Any dry fruit composed of multiple carpels that separate. : Under this definition the mericarps can contain one or more seeds (the m ...

s about 1 mm in size. Atypically for this group of plants, ''H. phoenix'' is a fire-ephemeral plant, meaning that it forms a

soil seed bank The soil seed bank is the natural storage of seeds, often dormant, within the soil of most ecosystems. The study of soil seed banks started in 1859 when Charles Darwin observed the emergence of seedlings using soil samples from the bottom of a lak ...

in the soil and its

germination Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, fer ...

is triggered by wildfire. It will typically not grow unless prompted by a wildfire. Like many plants from Australia, its life cycle requires fire. ''Hydrocotyle phoenix'' was discovered in 2015. It is most morphologically most similar to '' Hydrocotyle hispidula'', '' Hydrocotyle blepharocarpa'', and '' Hydrocotyle geraniifolia''. Its evolutionary position within ''Hydrocotyle'' has not yet been determined.

Range

''Hydrocotyle phoenix'' is only known from Karri Forest within

D'Entrecasteaux National Park D'Entrecasteaux National Park is a national park in Western Australia, south of Perth. The park is named after the French Admiral Bruni D'Entrecasteaux who was the first European to sight the area and name Point D'Entrecasteaux in 1792. The pa ...

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

. The plant is locally abundant, but due to having a very small range, it is currently listed as Priority 2 as not enough data exists to ascribe it a conservation code.

References

{{Taxonbar, from=Q51051224

Plants described in 2017 Eudicots of Western Australia Endemic flora of Western Australia