Synemon laeta Walker, 1854
Cheerful Sun Moth
(one synonym: Synemon vagans Westwood, 1877)
Don Herbison-Evans
Dave Britton & Stella Crossley

Synemon laeta
(Photo: copyright: Dave Britton)

The Caterpillars of this species differ from those of most other Synemon species in that they feed inside the culm of the foodplant at ground level, rather than on the roots underground. The only known foodplant for this species of Caterpillar is :

  • Spiny Headed Mat Rush ( Lomandra longifolia, ASPARAGACEAE ).

    Synemon laeta
    (Photo: copyright: Dave Britton)

    Unlike most other species of Synemon, the males show territorial behaviour, setting up territories around a perch (in this case a grass stem). Males chase intruding males away from the area around the perch. Immediately upon settling, males briefly display part of the bright hindwing, perhaps as a signal to any potentially interested females that might be around.

    (Photo: courtesy of CSIRO/BIO Photography Group, Centre for Biodiversity Genomics, University of Guelph)

    The adult moths have a brown pattern on the forewings, and scarlet hindwings each with a brown marginal and submarginal arc. The wingspan is about 5 cms.

    Synemon laeta
    drawing by Arthur G. Butler,

    Illustrations of typical specimens of Lepidoptera Heterocera in the collection of the British Museum,
    Part 1 (1877), Plate 3, fig. 4,
    image courtesy of Biodiversity Heritage Library, digitized by Gerstein Library, University of Toronto.

    This moth is common in dry open eucalypt bush on the east coast of

  • Queensland.

    Drawing by Embrik Strand
    Synemon - Epicop, Indo-Australian Bombyces and Sphinges,
    in Adalbert Seitz (ed.): The Macrolepidoptera of the World,
    Stuttgart : Alfred Kernen Verlag, Volume 10 (1933), Plate 9, fig b1,
    image courtesy of Biodiversity Heritage Library, digitized by Natural History Museum Library, London.

    Further reading :

    Ian F.B. Common,
    Moths of Australia, Melbourne University Press, 1990, pls. 6.23, 6.24, p. 285.

    Francis Walker,
    Catalogue of Lepidoptera Heterocera,
    List of the Specimens of Lepidopterous Insects in the Collection of the British Museum,
    Part 1 (1854), p. 36, No. 4.

    Australian Butterflies
    Australian Moths

    (updated 6 July 2009, 21 August 2018, 8 September 2019, 30 July 2021)