Cyathea exilis

Cyathea exilis. Photo: DERM Queensland Herbarium

Scientific name: Cyathea exilis

Family: Cyatheaceae

Conservation status: Cyathea exilis (C.exilis) is listed as Endangered in Queensland (Nature Conservation Act 1992) and nationally (Environment Protection and Biodiversity Conservation Act 1999). It is ranked as a high priority under the Department of Environment and Resource Management Back on Track species prioritisation framework.

Description

C. exilis is a slender tree fern with a trunk up to 2 m tall. The stalks of the fronds are approximately 20 cm long. The short prickles at the base of the leaves distinguish it from all other tree ferns on Cape York Peninsula.

Habitat and distribution

This species is only known from two small populations in spring-fed evergreen rainforest gullies on Cape York Peninsula. Within this specialised habitat, C. exilis is restricted to the steepest, most sheltered canyons. Here it grows on rocks or in hummocks fed by permanent groundwater. Additional surveys in areas of suitable habitat on the Glennie Tableland failed to locate C. exilis, and it is not known in areas of similar habitat elsewhere on Cape York Peninsula.

Life history and ecology

C. exilis regenerates from spores.

Threatening processes

Given the very small size of C. exilis populations, all are under threat. C. exilis is of interest to fern specialists, resulting in this tree fern being threatened by plant collecting for horticultural use.

Pig rooting (extensive digging to find food such as tubers, worms and soil invertebrates) may negatively affect C. exilis as disturbance to natural vegetation and the localised nature of this activity, can cause population declines or loss.

Recovery actions

Actions to prevent further decreases in numbers, populations and habitat of C. exilis include:

Implement public education programs to raise awareness about the impacts of collecting on C. exilis populations and habitat, and to discourage this activity.
Undertake pig control programs in areas where pig rooting is detected in C. exilis habitat.

What can you do to help this species?

Do not collect C. exilis plants from wild populations.
Avoid landscape modifications that disturb C. exilis habitat (e.g. vegetation removal and spring excavation which can alter land and groundwater supplies).

Last updated 24 November 2011