Regelia
Regelia is a genus of flowering plants in the family Myrtaceae. This genus is composed of six species of small leaved, evergreen shrubs and trees that are endemic to Australia. Five of the six species are endemic to the south-west of Western Australia. The sixth species that has been assigned to this genus (R. punicea) is endemic to Kakadu National Park in the Northern Territory and is now considered to belong to a new separate genus, Petraeomyrtus. Regelia species range from 1 to 6 meters in height.[1] They are noted for bearing essential oils.[1] Typically showy blooms are aggregate inflorescences which take the form of heads or spikes depending upon the species. Fruits are a woody, 3-valved capsule which often split upon maturity.
Etymology and taxonomy
The genus was first formally described by J.C.Schauer in 1843 who gave it the name Regelia in honour of German gardener and botanist Eduard August von Regel.[1]
Regelia is closely related to Melaleuca; both have stamens which are fused into clusters. The primary difference between the genera is that in Regelia the anthers are attached at the base and in Melaleuca they are attached at the side.[2] These genera are also closely related to Beaufortia, Calothamnus and Eremaea.[2]
Species
There are currently six recognized species of Regelia. All are endemic to small geographic regions in southwestern or north-central Australia.
- Regelia ciliata Schauer is a rigid spreading shrub which grows 1.3 m to 1.5 m across. It has tiny wedge shaped leaves, and paper-like bark on the stems.[3]
- Regelia cymbifolia (Diels) C.A.Gardner is a much branched, upright shrub of about 2 meters in height, and bearing tiny wedge shaped leaves. It blooms in the spring, producing clusters of many small heads.
- Regelia inops (Schauer) Schauer is an upright but often spreading shrub which can grow to 0.75–2.5 m and has tiny wedge shaped leaves.[4]
- Regelia megacephala C.A.Gardner is a rare, 2-5 meter tall shrub, which has larger (but still small) rounded leaves.[5]
- Regelia velutina (Turcz.) C.A.Gardner (Barrens regelia) is the showiest and largest member of the genus. It is a large shrub or small tree which can grow up to 6 meters. It is noted for growing on very poor dry soils and having large flower heads.[6]
- Regelia punicea (N.Byrnes) Barlow is found in the Northern Territory. This species was reassigned from genus Melaleuca in 1986 [7] but subsequently was proposed as a member of a new separate genus, Petraeomyrtus,[8] within which its species name is Petraeomyrtus punicea (Byrnes) Craven. [9]
References
- ^ a b c Regelia Florabase: The Western Australian Flora (ID 21844)
- ^ a b Association of Societies for Growing Australian Plants (ASGAP): Regelia cymbifolia
- ^ Regelia ciliata Australians National Botanic Gardens, Australian Government.
- ^ R. inops FloraBase: The Western Australian Flora.
- ^ R. megacephala FloraBase: The Western Australian Flora.
- ^ R. velutina FloraBase: The Western Australian Flora.
- ^ Regelia punicea (N.Byrnes) Barlow, comb.nov. (Myrtaceae) from the Northern Territory: Phytogeographic implications. Barlow, BA. 1986, in Brunonia 9(1) 89 - 97. Australian Systematic Botany.
- ^ Generic position of Melaleuca punicea: Petraeomyrtus, gen. nov. (Myrtaceae), Craven, LA. 1999, in Australian Systematic Botany 12(5) 675 - 678
- ^ Recruitment dynamics of the long-lived obligate seeders Callitris intratropica (Cupressaceae) and Petraeomyrtus punicea (Myrtaceae), Russell-Smith, Jeremy. 2006, in Australian Journal of Botany 54(5) 479–485
External links