Nature conservation

Threatened species

Tetratheca glandulosa - profile

Indicative distribution


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Key:
known
predicted
The areas shown in pink and/purple are the sub-regions where the species or community is known or predicted to occur. They may not occur thoughout the sub-region but may be restricted to certain areas. ( click here to see geographic restrictions). The information presented in this map is only indicative and may contain errors and omissions.
Scientific name: Tetratheca glandulosa
Conservation status in NSW: Vulnerable
Commonwealth status: Not listed
Profile last updated: 21 Aug 2019

Description

Small, spreading shrub which grows 20 - 50cm in height. Stems often become entwined among other small shrubs, sedges and grasses. Leaves are opposite 5 - 10 mm long and 1 mm wide with recurved (rolled under) margins. Leaf margins have small stiff hairs that give them a “toothed” appearance. The flower stalk and sepals (leaf-like structure at base of flower) are covered with dark-red gland-tipped hairs, which distinguishes T. glandulosa from other Tetratheca species. T. glandulosa flowers have four petals, which are dark pink, or occasionally pale pink. The flower stalk is 3 - 10 mm long and the petals are approximately 4.5 - 10.5 mm long.

Distribution

Restricted to the following Local Government Areas: Baulkham Hills, Gosford, Hawkesbury, Hornsby, Ku-ring-gai, Pittwater, Ryde, Warringah, and Wyong. There are approximately 150 populations of this plant ranging from Sampons Pass (Yengo NP) in the north to West Pymble (Lane Cove NP) in the south. The eastern limit is at Ingleside (Pittwater LGA) and the western limit is at East Kurrajong (Wollemi NP). There are historical collections of this species south to Manly, Willoughby and Mosman, however these populations are now extinct. The current north-south range is approximately 65km.

Habitat and ecology

  • Associated with shale-sandstone transition habitat where shale-cappings occur over sandstone, with associated soil landscapes such as Lucas Heights, Gymea, Lambert and Faulconbridge. Topographically, the plant occupies ridgetops, upper-slopes and to a lesser extent mid-slope sandstone benches. Soils are generally shallow, consisting of a yellow, clayey/sandy loam. Stony lateritic fragments are also common in the soil profile on many of these ridgetops.
  • Vegetation structure varies from heaths and scrub to woodlands/open woodlands, and open forest. Vegetation communities correspond broadly to Benson & Howell’s Sydney Sandstone Ridgetop Woodland (Map Unit 10ar). Common woodland tree species include: Corymbia gummifera, C. eximia, Eucalyptus haemastoma, E. punctata, E. racemosa, and/or E. sparsifolia, with an understorey dominated by species from the families Proteaceae, Fabaceae, and Epacridaceae.
  • Flowers July-November however residual flowers may persist until late December. Flowering influenced by seasonal weather conditions and/or the microclimate effects (eg. exposure) of each particular site.
  • The age of individual plants is difficult to determine and the life span of the plant is unknown. Life expectancy is approximately six to ten years, however, based on field investigations which indicate that the plant resprouts from a woody root following fire, this may be an underestimate.
  • The breeding system for this species is poorly known. In comparison to a similar species, Tetratheca juncea, it is expected that this plant is unable to self-pollinate due to the physical characteristics of the plant’s reproductive parts, and that a pollen vector (possibly a species of native bee) is required for successful pollination.
  • Seedbank dynamics (fecundity, viability, dispersal, longevity, dormancy etc) for this species are poorly known. Juveniles appear to be uncommon within any given population, with the majority of plants usually consisting of resprouting adults.
  • Resprouts from a woody root following fire, however the role fire plays in seed germination and persistence of the species is unclear. In a similar species, Tetratheca hirsuta, it has been shown that exposure of the seed to cold smoke and/or smoked water derived from burnt native vegetation promoted germination.
  • Field observations following fire indicate that the plant is likely to be clonal.
  • Tetratheca species are reported to be readily propagated by cuttings, however the long term survival of these plants is poorly known.

Regional distribution and habitat

Click on a region below to view detailed distribution, habitat and vegetation information.


Threats

Recovery strategies

Activities to assist this species

Information sources

IBRA Bioregion IBRA Subregion Known or predicted Geographic restrictions region
Sydney BasinBurragorang Known None
Sydney BasinCumberland Known None
Sydney BasinPittwater Known None
Sydney BasinWollemi Known None
Sydney BasinWyong Known None
Sydney BasinYengo Known None