Synemon plana

Synemon plana
Synemon plana male (left) and female (right)
Conservation status
Vulnerable  (EPBC Act)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Lepidoptera
Family:	Castniidae
Genus:	Synemon
Species:	S. plana
Binomial name
Synemon plana Walker, 1854
Synonyms
Synemon hesperioides R. Felder, 1874 Synemon maculata Strand, 1911

Synemon plana, commonly known as the golden sun moth, is a

A description of the species was published in 1854 (Lepidoptera: Castniidae), as a medium-sized (wingspan 31–34 mm), day-flying moth species.[2] Up until recently, the species had been listed as critically endangered, attracting the status of a flagship species towards the conservation of natural temperate grassland.^[3]

Description

The golden sun moth is a medium sized, day-flying moth with distinct green eyes and clubbed antennae. The antennae are a notable feature of Synemon plana; as most other moths have brushy antennae. Listed as vulnerable under the EPBC Act 1999,^[1] it is synonymous with Rytidosperma species of grasses and is almost completely confined to grasslands which include many of these grass species. At least a 40% cover of Rytidosperma species is optimal for the species.^[4]

Male Synemon plana are dull in colour, the forewings consisting of dark brown, patterned with pale grey and the hind wings are brown with darker brown patches.^[2] Female Synemon plana are brighter in colour with the forewings of brown and grey patterns,

the forewings are a bright golden brown colouring with dark brown patches on the outer margin of the hindwings. This golden colouring gives Synemon plana its common name, the golden sun moth.^[3] Female Synemon plana are generally flightless, with small hindwings in comparison to the male.

Life cycle

The life cycle of the golden sun moth is relatively well understood. Longevity is estimated to be about two years (Edwards 1994), however, genetic evidence suggests that

Adults only live for one to two days, as they lack functional mouthparts and are unable to feed.^[3]

Distribution

The golden sun moth endemic to Australia, is primarily confined in south-eastern native temperate grasslands which possess a high density of wallaby grasses (e.g. Rytidosperma spp.).^[5]

Historically, the golden sun moth maintained a wide and likely continuous distribution in native temperate grasslands and open grassy woodlands at the time of

Potential habitat for the moth includes any areas which have or once had grassy woodlands or native grasslands throughout the historical range of the species. The golden sun moth has been known to inhabit substantially degraded grasslands, including those dominated by the introduced Chilean needlegrass (Nassella neesiana). Two threatened ecological vegetation communities listed under the EPBC Act are known habitat sources for the moth – the ‘Natural Temperate Grassland of the Southern Tablelands of NSW and the ACT', and the ‘Natural Temperate Grassland of the Victorian Volcanic Plain’ (see EPBC Act Policy Statement 3.8).  

Conservation Listing

As of December 7, 2021, under the Environmental Protection and Biodiversity Conservation Act 1999 (EPBC Act), the golden sun moth is listed as vulnerable.^[1][7] It has also been listed as a vulnerable taxon under the Victorian Flora and Fauna Guarantee Act 1988 and the New South Wales Biodiversity Conservation Act 2016. ^[7] It is also listed as endangered under the Australian Capital Territory Nature Conservation Act 2014.^[7] The golden sun moth national recovery plan is in preparation by the NSW Department of Environment and Climate Change. ^{[citation needed]}

Conservation

Golden sun moth populations have undergone substantial surveying and study, including through mitochondrial DNA analysis and allonym electrophoresis.^[8][9][6] Conventional management actions for the species have included measures to improve habitat quality for the golden sun-moth, via the re-establishment of native grasses, weed and biomass removal, as well as efforts to reduce their mortality rates through predator control.^[10][11] In environments where remnant habits co-exist with urban, management using a biodiversity sensitive urban design has been explored.^[11]

Sightings

In January 2021, a moth was sighted and photographed by a man walking his dog in

The major threat to existing golden sun moth populations is the loss and degradation of grassland habitat and the subsequent changes in vegetative composition.[5] Predation, frequent and/or intense fire and their small, isolated and fragmented populations are also likely threats.^[3] The native grasslands and grassy woodlands habitat of the moth are the most threatened of all vegetation types in Australia, with an estimated 99.5% being heavily altered or destroyed.^[4][5] The integrity of this minuscule remaining native grassland has been impacted further by introduced pasture grasses and clovers, outcompeting the native Austrostipa and Rytidosperma species, as well as contributing to other ramifications. Predation from birds including the willie wagtail (Rhipidura leucophyrs), starling (Sturnus vulgaris), magpie lark (Grallina cyanoleuca) and welcome swallow (Hirundo neoxena), as well as predatory insects such as the robber fly (Asilidae) can contribute to adult golden sun moth mortality. While the golden sun moth is locally abundant at many small patches, majority of these sites are public areas and therefore, at risk to disturbance. The fragmentation and isolation of these populations further prohibits the ability for relatively immobile females to recolonise areas, reducing genetic change.^[3][8]

See also

• Threatened fauna of Australia

References