Drosera, commonly known as the sundews, is one of the largest genera of carnivorous plants, with at least 194 species. These members of the family Droseraceae lure, capture, and digest insects using stalked mucilaginous glands covering their leaf surfaces. The insects are used to supplement the poor mineral nutrition of the soil in which the plants grow. Various species, which vary greatly in size and form, are native to every continent except Antarctica.
Drosera fimbriata, the Manypeaks sundew, is a perennial tuberous species in the genus Drosera that is endemic to Western Australia. It grows to 10 to 15 cm tall with two or three whorls of non-carnivorous leaves on the lower portion of the stem and 2 to 5 whorls of carnivorous leaves above that. It is native to a region mostly around Manypeaks but with populations near the Scott River and near Denmark. It grows in winter-wet sandy soils in heathland. It flowers in October.
Drosera humilis is a perennial tuberous species in the genus Drosera that is endemic to Western Australia. It has 3 to 5 semi-erect stems that are 3 to 15 cm long with carnivorous leaves arranged in whorls around the stems. It is native to a region from the Moore River north to Kalbarri and east to Ajana and Wongan Hills. It grows in winter-wet sandy soils in heathland. It flowers from June to September.
Drosera platypoda, the fan-leaved sundew, is a tuberous perennial species in the genus Drosera that is endemic to south-west Western Australia. It grows 15 to 20 cm tall with a basal rosette of leaves with alternate cauline leaves along the stem. It is native to a region from Manjimup south-west to an area around the Scott River and east to Cape Riche. It grows in winter-wet sandy soils in heathland. It flowers in October.
Drosera porrecta is a tuberous perennial species in the genus Drosera that is endemic to Western Australia. It grows up to 45 cm tall. It is native to a region from Eneabba and Marchagee south to an area around Pinjarra, including the Darling Range and Mount Cooke. It grows in well-drained sandy soils and flowers from July to September.
Drosera prostrata is a tuberous perennial species in the genus Drosera that is endemic to Western Australia. It produces 4 to 5 prostrate lateral stems that are 3.5 to 15 cm long. The prostrate growth habit is what sets it apart from all other members of the section Stolonifera. It is native to a region along the Western Australian coast from the Tamala area near Shark Bay south to Binnu. It grows in well-drained sandy soils and flowers from May to June.
Drosera purpurascens is a compact tuberous perennial species in the genus Drosera that is endemic to south-west Western Australia. It produces 1 erect or 2 to 5 semi-erect lateral stems that grow to 3 to 10 cm long. The compact size of the plant combined with relatively long petioles distinguish it from all other members of the section Stolonifera. It is native to a region from Mount Cooke to near Katanning and Ongerup south to the Denmark-Albany region. It grows in sand-laterite soils and flowers from July to October, flowering en masse after bushfires.
Drosera ramellosa, sometimes referred to as the branched sundew, is a tuberous perennial species in the genus Drosera that is endemic to Western Australia. It was first formally described by Johann Georg Christian Lehmann in 1844. It was again described by Jules Émile Planchon as Drosera penduliflora in 1848, which was reduced to synonymy under D. ramellosa in 1864 by George Bentham.
Drosera rupicola is a tuberous perennial species in the genus Drosera that is endemic to Western Australia. It produces 3 to 5 semi-erect lateral stems that grow up to 15 cm long. The turbinate tuber and mobile lamina that are capable of folding over prey distinguish it from all other members of the section Stolonifera. It is native to a large inland region from Pithara to south-east of Hyden. It grows in loamy soils near granite outcrops and flowers from July to October.
Drosera stolonifera, sometimes referred to as the leafy sundew, is a tuberous perennial species in the genus Drosera that is endemic to Western Australia. It produces 2 to 3 semi-erect lateral stems that grow 10 to 15 cm long. It is most closely related to D. purpurascens, but differs by several characteristics including height and petiole length. It is native to a number of swampy locations around Perth south to Pinjarra. It grows in peaty water-logged soils in swamp heathland and flowers from September to October. After a bushfire it will flower en masse.
Drosera sect. Stolonifera is a section of ten tuberous perennial species in the genus Drosera that are endemic to south-west Western Australia. The species all have a similar growth habit and all have fan-shaped leaves, but the morphological differences and lack of natural hybrids support the division of the D. stolonifera species complex.
Drosera erythrorhiza, the red ink sundew, is a perennial tuberous species in the carnivorous plant genus Drosera that is endemic to Western Australia. It grows in a rosette and is distinguished from the other species in section Erythrorhiza by its many-flowered cymose inflorescences with up to 50 individual flowers. D. erythrorhiza was first described by John Lindley in his 1839 publication A sketch of the vegetation of the Swan River Colony. In 1992, N. G. Marchant and Allen Lowrie described three new subspecies, thus also creating the autonym D. erythrorhiza subsp. erythrorhiza. The subspecies were separated from this variable species mostly by leaf morphology and distribution.
Drosera zonaria, the painted sundew, is a perennial tuberous species in the carnivorous plant genus Drosera and is endemic to south-west Western Australia from near Perth southeast to near Esperance. It grows in a tight rosette approximately 5 to 7 cm in diameter with 20 to 30 green to red leaves that are arranged in concentric layers. The leaves are typically 1 cm wide and are usually described as being "kidney-shaped" with crimson leaf margins. It grows in deep silica sands in open woodland or coastal heathland and only flowers after a bush fire, which is speculated to be caused by the release of ethylene. Its white, sweetly perfumed flowers, which are very similar to those of D. erythrorhiza, emerge on 4 to 5 cm tall scapes. As with most other tuberous Drosera species, D. zonaria will die back during the dry summer months and retreat to the fleshy tuber 10 to 30 cm below ground.
Drosera sect. Erythrorhiza is a section of 14 species of tuberous species in the genus Drosera. It represents a natural group of all the rosetted tuberous Drosera. Most species are endemic to Western Australia, but D. aberrans, D. praefolia, D. schmutzii, and D. whittakeri are also found in eastern Australia.
Drosera microphylla, the golden rainbow, is an erect perennial tuberous species in the carnivorous plant genus Drosera. It is endemic to Western Australia and grows on granite outcrops or in sandy or laterite soils. D. microphylla produces small, circular, peltate carnivorous leaves along erect stems that can be 10–40 cm (4–16 in) high. It blooms from June to September, displaying its large golden sepals and smaller, variably-coloured petals. In populations near Perth, the petals are red, whereas petal colour near Albany tends to be orange. Some plants east of Esperance have white petals.
Drosera subhirtella, the sunny rainbow, is a scrambling or climbing perennial tuberous species in the carnivorous plant genus Drosera. It is endemic to Western Australia and is found in sandplains, granite outcrops, and swamp margins in sand, clay, and loam soils. D. subhirtella produces small carnivorous leaves along stems that can be 40 cm (16 in) high. Yellow flowers bloom from August to October.
Drosera subtilis is an erect annual species in the carnivorous plant genus Drosera. It is native to northern Western Australia and a single site in the Northern Territory. In Western Australia, it has been collected from Beverley Springs Station, Bigge Island, and the Mitchell Plateau area all in the vicinity of the Kimberley region. In the Northern Territory, it has been found near Little Nourlangie Rock. It grows over sandstone near seepage margins in skeletal sandstone sand and black humus mixed soils. D. subtilis is anchored to the soil by a system of thin, fleshy roots and it lacks a tuber. It produces small carnivorous leaves along erect, reddish stems that can be 20 cm (8 in) high.
Drosera sect. Ergaleium is a section of 26 species that are erect or scrambling tuberous plants in the genus Drosera. This section represents a natural group and are taxonomically monophyletic.
Drosera subg. Thelocalyx is a subgenus of two species in the genus Drosera. Both species appear to be very similar and are often confused in cultivation; both have small leaves arranged in a rosette and are annual plants. Their distributions do not overlap, however, with D. burmannii in Southeast Asia and Australia and D. sessilifolia in Brazil, Guyana, and Venezuela.
Drosera subg. Lasiocephala, sometimes collectively known as the petiolaris-complex, is a subgenus of 14 species in the genus Drosera. These species are distinguished by their subpeltate to peltate lamina.
