Action Statement Flora and Fauna Guarantee Act 1988 No. 146 Five threatened Victorian Sun- moths (Synemon species) Description and distribution The Sun-moths (family Castniidae) are Female sun-moths mate and commence considered to have a Gondwanan origin as they oviposition shortly after emergence from their occur in the Neotropical, Australian and Oriental pupae as all of their eggs are fully matured regions. The Australian species are all placed in during the pupal stage. They have long, the single genus Synemon, containing 20 retractable ovipositors that are used to deposit described and 22 undescribed species (E. D. their eggs beneath the soil, at or near the base Edwards pers. comm.). of their larval food plants. After hatching, the larvae tunnel to the food plants roots or Sun-moths are broad-winged, colourful, day- rhizomes and commence feeding. Prior to flying moths with clubbed antennae and pupation each larva constructs a vertical, silk- relatively slender bodies. Their diurnal habits lined tunnel to just below the soil surface from are so strong that if passing clouds block out which the empty pupal casing protrudes after the sunshine they will immediately settle and the adult moth has emerged. not take flight again (unless disturbed) until sunlight returns. They usually fly rapidly, It is not known how long any of the Victorian within a metre of the ground and keep their sun-moths take to complete their life cycles. wings in motion continuously. When Sun-moths However, Common and Edwards (1981) found rest for short periods they often raise and lower that Synemon magnifica, a species that occurs their wings rhythmically, showing their brightly in New South Wales, takes two to three years to coloured hindwings. However, when resting for complete a generation. The known larval host longer periods the hindwings are concealed by plants of the eight species of Victorian sun- cryptically coloured forewings that harmonise moths are invariably monocotyledons and perfectly with the surrounding debris and soil belong to the families Cyperaceae, surface crust. Unlike most moth families, the Xanthorrhoeaceae, Poaceae and Juncaceae. Sun-moths are unable to fold away their Conservation status antennae when at rest. Synemon nais and S. theresa have been listed as General life history and ecology of sun- threatened under the Flora and Fauna moths Guarantee Act 1988. As adults, sun-moths have relatively brief lives There is at present no authoritative list of of approximately four to ten days (depending on threatened invertebrates in Victoria. the species). The adults of some sun-moths None of these species is listed as threatened have reduced mouthparts and do not feed. under the Environment Protection and These species rely on nutrients that are stored Biodiversity Conservation Act 1999. in their bodies during the larval stage to sustain them through their short adult lives. Conservation objectives References Common, I. F. B. & Edwards, E. D. (1981) The life Long term objective - all species history and early stages of Synemon magnifica Strand (Lepidoptera: Castniidae). J. Aust. Ent. To ensure that the five species of sun-moth Soc. 20: 295-302. survive, flourish and retain their potential for evolutionary development in the wild by protecting Common, I. F. B. & Waterhouse, D. F. (1981) Butterflies of Australia. Angus & Robertson: and enhancing their habitat. Sydney. Common, I. F. B. (1990) Moths of Australia. Objectives of this Action Statement - all species Melbourne University Press: Carlton. 1. Achieve long-term protection and sympathetic DSE (2004) Atlas of Victorian Wildlife (electronic management of key Sun-moth sites. fauna database). Department of Sustainability & Environment. Biodiversity & Natural Resources 2. Improve current understanding of Division: Melbourne. distribution, abundance, biology and habitat requirements of Sun-moth. 3. Increase public awareness of Sun-moth and other grassland-dependent invertebrates. Intended Management Action The intended management actions listed below are further elaborated in DSE’s Actions for Biodiversity & Conservation database. Detailed information about the actions and locations, including priorities, is held in this system and will be provided annually to land managers and other authorities. Generic actions 1. Provide information and advice, including maps, regarding the location and management Compiled by Fabian Douglas, consultant of sun-moth sites to landholders, land entomologist. managers and other authorities, especially Catchment Management Authorities and local Further information can be obtained from government authorities. Department of Sustainability and Environment Customer Service Centre on 136 186. Responsibility: DSE (Biodiversity & Natural Resources Division, SW Region) Flora and Fauna Guarantee Action Statements are 2. Incorporate actions to protect, enhance and available from the Department of Sustainability and restore sun-moth habitat into relevant Environment website: http://www.dse.vic.gov.au Regional Catchment Strategies or their subordinate strategies via Biodiversity Action This Action Statement has been prepared under section 19 of the Flora and Fauna Guarantee Act Plans. Implement these actions, according to 1988 under delegation from Professor Lyndsay priority, as resources become available, in Neilson, Secretary, Department of Sustainability and conjunction with other agencies, community Environment, September 2003. groups and landholders. © The State of Victoria, Department of Responsibility: Catchment Management Sustainability and Environment, 2003 Authorities 3. Incorporate information regarding the location Published by the Department of Sustainability and and management of sun-moth sites into local Environment, Victoria. 8 Nicholson Street, East Melbourne, Victoria 3002 Australia planning schemes, including environmental significance overlays, and apply the Victorian Planning Provisions so as to protect these This publication may be of assistance to you but the State of Victoria and its employees do not guarantee sites. that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and Responsibility: Shires therefore disclaims all liability for any error, loss or other consequence which may arise from you Species-specific actions relying on any information in this publication. For detailed information, including specific ISSN 1448-9902 Intended Management Actions, refer to the following pages on each species. 2 Small Orange-spotted Sun-moth Synemon discalis Strand 1911 Description and distribution A medium-sized sun-moth with a series of prominent bright orange spots on the black uppersides of the hindwing. Wingspan is about 3.1cm in males and 3.5 cm in females. In the Big Desert, this species is on the wing concurrently with the superficially similar Orange-spotted Sun- moth (Synemon parthenoides) with which it can be easily confused. The Small Orange-spotted Sun-moth can be distinguished by its smaller size, narrower wings, paler wing undersides and bronzy-grey rather than blackish- grey upper forewings. Note: E. D. Edwards has indicated that the Synemon species illustrated in Common (1990) as ‘S. ?discalis’ is actually an undescribed species from Western Australia. Within Victoria this species is only known to occur at two localities: in the south-eastern corner of the Big Desert, occupying an area of about 2 ha and 6 km north of Hattah on the Calder Highway. This record is based on a single female collected in October 1995. Outside Victoria the Small Orange-spotted Sun-moth occurs in limited areas on the Yorke and Eyre Peninsulas in South Australia and at Mount Ragged and Norseman in Western Australia (E. D. Edwards pers. comm.). However, E. D. Edwards has indicated that the populations in Western Australia may belong to a closely allied but separate species. Common (1990) states that Synemon discalis is “…widely distributed in western Victoria and South Australia”. However, this is an error as this species has a restricted distribution in South Australia and was not known to occur in western Victoria until 1995. Habitat Big Desert site: Low lying, open heathland on greyish-white sands. The dominant plant species at the one Victorian site are as follows: Gahnia lanigera (Desert Saw-sedge), Lepidosperma carphoides (Black Rapier- sedge), Lepidosperma viscidum (Sticky Sword-sedge), Triodia scariosa (Porcupine Grass), Dampiera rosmarinifolia (Rosemary Dampiera) and Kunzea pomifera (Muntries). Although trees and shrubs are scarce at the site there are a few specimens of Eucalyptus leptophylla (Narrow-leaf Mallee) and Leptospermum coriaceum (Green Tea-tree) near its margin. Hattah site: An undulating mallee community on a reddish, sandy soil. The most abundant mallee species at the site are Eucalyptus socialis (Grey Mallee) and Eucalyptus costata (Yellow Mallee). Although the ground flora is dominated by Triodia scariosa (Porcupine Grass), the area also contains scattered occurrences of Gahnia lanigera (Desert Saw Sedge). Other plants that occur at the site include: Lepidosperma viscidum (Sticky Sword- sedge), Westringia rigida (Stiff Westringia), Leptospermum coriaceum (Green Tea-tree) and Baeckea behrii (Broom Baeckea). Life history and ecology At the Big Desert site this species is on the wing from late-October to mid-November, with the highest numbers being recorded in early November. In most instances the females were recorded ovipositing at the base of Gahnia lanigera (Desert Saw-sedge) plants