Gonocarpus tetragynus
Gonocarpus tetragynus is an Australian herb in the watermilfoil family Haloragaceae native to eastern Australia.[1] Common names include common raspwort.[2] A widespread species particularly found in dry eucalyptus forests, scrubland, and heathland.[1]
| Gonocarpus tetragynus | |
|---|---|
| Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Order: | Saxifragales |
| Family: | Haloragaceae |
| Genus: | Gonocarpus |
| Species: | G. tetragynus |
| Binomial name | |
| Gonocarpus tetragynus | |
| Synonyms | |
| Synonymy
| |
Description edit
The herb can grow erect or ascend to 15-30 cm (5.9-11.8 in) tall. The many wiry branching stems can be smooth or are weakly 4-ribbed. Leaves are decussate, lanceolate and range from 0.6-1.2 cm (0.2-0.5 in) long. The leaf margins are thickened, irregularly toothed and recurved. The leaves are attached to petioles, 0.5-1 mm (0.020-0.039 in) long. The bracts are sessile, alternate, lanceolate, and range from 2-2.5 mm (0.079-0.098 in) long. The bracteoles are membranous, lanceolate to linear-lanceolate, 0.8-1.2 mm (0.031-0.047 in) long.[3] Both the leaves and the stem are covered in white-appressed hairs, which gives a rough texture.[3][4]
The species is perennial.[3][4] The flowers are bisexual, but in the occasional individual, they become functionally female, after the abortion of the stamens and the petals.[3] The flowering time ranges from Spring to Summer; as early as September and as late as February.[3][4][5] The inflorescence is a spike with tiny solitary flowers which are 1-3 mm (0.039-0.12 in) across.[3][4] Like in other members of the Haloragaceae family, the flowers are divided into 4 whorls. The sepals are deltoid and green, with a prominent basal callus. Petals range from green to red and are hooded and keeled. The herb has 8 stamens and an 8-ribbed ovary.[3]
The fruit is a dry nut, a family characteristic.[3] The herb develops a ridged, globular nut.[3][4] It is 1-1.3 mm (0.039-0.051 in) long.[3] The colour ranges from silver-grey to slate grey.[3]
Taxonomy edit
Jacques Labillardière first formally described the species as G. tetragyna in 1805; as published in Novae Hollandiae Plantarum Specimen 1.[6] Its variant, Gonocarpus tetragynus, would be the accepted name by 2005, according to the Australian Plant Census of the same year.[6]
Several other synonyms are known including Goniocarpus tetragynus, Haloragis gonocarpus, Haloragis tetragyna, Halorrhagis tetragyna, Gonocarpus tenellus, Haloragis rubra, Halorrhagis rubra.[6]
Distribution and habitat edit
The species is widespread, in terrestrial Eastern Australia. It occurs in Queensland, New South Wales, ACT, Victoria, South Australia, and Tasmania.[3] The herb can also be found in the Flinders and Clarke islands in the Bass Strait.[3] While widespread it is particularly found in moist to dry soils in dry Eucalyptus forests, shrublands, and heathlands.[1] In Tasmania, it is commonly found on dry stony outcrops.[4]
Records of this species in other countries are based on miss identification of G. incanus, G. montanus, G. chinensis, and G. philippinensis.[3]
Distinguishing from similar species edit
Gonocarpus tetragynus is similar in appearance to Gonocarpus humilis. The two species can be distinguished by the former's lanceolate leaves, an even cover of white-appraised hairs and the flower’s 8 stamens.[3]
Cultivation edit
Cultivation of the species is possible, but it is not widely grown.[4]
References edit
- ^ a b c Peter G. Wilson. "Gonocarpus tetragynus". PlantNET - New South Wales Flora Online. Royal Botanic Gardens & Domain Trust, Sydney Australia. Retrieved 2 August 2014.
- ^ "Gonocarpus tetragynus Labill". Australian Plant Name Index (APNI), IBIS database. Centre for Plant Biodiversity Research, Australian Government.
- ^ a b c d e f g h i j k l m n o Flora of Australia Volume 18, Podostemaceae to Combretaceeae. Australian Government Publishing Service. 1990.
- ^ a b c d e f g Howells, Christine (2021). Tasmania's Natural Flora (3rd ed.). Hobart: Australian Plants Society Tasmania Inc., Hobart Group. p. 213.
- ^ "Yarra Ranges Local Plant Directory". www.yarraranges.vic.gov.au. Retrieved 2023-03-18.
- ^ a b c Australia, Atlas of Living. "Species: Gonocarpus tetragynus (Common Raspwort)". bie.ala.org.au. Retrieved 2023-03-18.