| Craspedia paludicola | |
|---|---|
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Asterales |
| Family: | Asteraceae |
| Genus: | Craspedia |
| Species: | C. paludicola |
| Binomial name | |
| Craspedia paludicola J.Everett & Doust [1] | |
 | |
| Distribution of Craspedia paludicola [2] | |
Craspedia paludicola, commonly known as the swamp billy-buttons, is a perennial robust herb native to Australia.
Craspedia paludicola is an upright, rosette-forming herb [3] with a vegetative height of 25 to 75 cm (9.8 to 29.5 in), belonging to the Asteraceae family. [2]
The flaccid leaves are 150 to 400 mm (5.9 to 15.7 in) long and 8 to 20 mm (0.31 to 0.79 in) wide, [2] basal and cauline, narrow-oblanceolate, obtuse, attenuate at the base and broadly stem clasping. [4] They have one to several prominent longitudinal veins and are glabrous or with few scattered finely woolly or multiseptated white hairs that are sometimes denser on the margins or midrib. [5] The leaves are dark grey-green [3] or olive-green, usually with a red base and the old leaf-bases are retained. [5]
Each plant has one to three flowering scapes, reddish to purplish in colour, up to 75 cm (30 in) in height [3] and scattered with fine hairs. [5]
The inflorescence is bright-yellow single globular compound or button-like head [3] 1.7 to 3 cm (0.67 to 1.18 in) in diameter with up to 300 capitula on peduncles 2 to 5 mm (0.079 to 0.197 in) long. [5] Each capitula or head consists of 7 to 12 florets with bright yellow corollas surrounded by a ring of bracts with glandular, silky hairs, [4] the main bract deltoid to ovate shaped with membranous margins. [5] Cypselas (seeds) are 1 to 1.8 mm (0.039 to 0.071 in) with a pappus 3 to 4 mm (0.12 to 0.16 in) long. [4] Flowers bloom September to February. [3]
Craspedia paludicola is widespread in Victoria and southeastern New South Wales (including the Australian Capital Territory), considered rare in Tasmania and considered vulnerable in South Australia. [2] [6] Outlying occurrences can be found in northern New South Wales and southern Queensland historical records have been found at a site in Western Australia. [6]
In Tasmania, the species is scattered across 14 locations, recorded in lowland areas across the eastern side of the state, and up to 1,200 m (3,900 ft) above sea level in montane sites in the Central Highlands. [6] It is considered uncommon in wet subalpine and alpine areas. [3]
Although rarely encountered, the species can be abundant in small occurrences. [6] and considered locally common on heavy clay soils and is tolerant of inundation, often found partially submerged. [7] It typically grows around bodies of water [8] including the edges of lakes, lagoons, rivers, creeks and streams, or in open wet areas that are inundated temporarily, such as bogs, swamps, ponds, and ditches. It is found in a variety of vegetation types including open wetlands, marshland, rushland, sedgeland and grassland. [6]
The abundance and distribution of the species is likely regulated by conditions that maintain, or require disturbance to create, open recruitment niches. [6] It is likely that conditions providing protection from grazers, such as steep banks, can support the dominance of the species. [9]