Crypsiphona ocultaria (Donovan, 1805)
Red-lined Geometrid
(erroneously : Phalaena occultaria Guenée, 1857)
Don Herbison-Evans
Stella Crossley

Crypsiphona ocultaria
close-up of first instar
(Photo: courtesy of David Akers, Won Wron, Victoria)

The first instar of this Caterpillar is grey, with a rounded yellow head and a fork at the rear.

Crypsiphona ocultaria
(Photo: courtesy of Amy Prendergast, Perth, Western Australia)

In later instars, the head changes to taper to a point at the front, and a pale red-edged yellow lateral line develops, extending each side from the tip of the head to the tip of the tail.

Crypsiphona ocultaria
(Photo: courtesy of Marita Macrae, Avalon Beach, New South Wales)

These later instars rest with the true legs tucked forwards around the mouth parts, so that its head capsule is almost hidden.

Crypsiphona ocultaria
close-up of head with legs extended for walking
(Photo: courtesy of Amy Prendergast, Perth, Western Australia)

The caterpillar feeds on the leaves of

  • Gum Trees ( Eucalyptus and Angophora species, MYRTACEAE ).

    To feed, the first instar bends over the leaf and eats the surface layer. Later instars eat the whole leaf from the edge inwards. The caterpillar moves very little, clinging to the same position on the same leaf for several days at a time. When it does move, mouth parts and legs separate and point downwards. This makes the projection behind the head point upwards, like a conical hat.

    Crypsiphona ocultaria
    (Photo: courtesy of Merlin Crossley, Melbourne, Victoria)

    The caterpillar looks pretty as it 'tip toes' along a leaf: first the front end moves ahead, then the rear end loops forward to join it.

    Crypsiphona ocultaria
    (Photo: courtesy of Amy Prendergast, Perth, Western Australia)

    When disturbed, the Caterpillar stands out stiffly like a twig. standing on its anal prolegs and the single pair of ventral prolegs. This is fine if it is on a twig, but is conspicuous when it happens to be on the edge of a leaf. Perhaps their normal predators are too silly to notice.

    Crypsiphona ocultaria
    (Photo: courtesy of Steve Williams, Moths of Victoria: Part 4)

    In captivity the caterpillars pupated four weeks after hatching from the egg. The pupa was formed in the soil. The adult moths emerged two weeks after pupation in February in Melbourne.

    Crypsiphona ocultaria
    (Photo: courtesy of Andrew Wright, Canberra, Australian Capital Territory)

    The adult is unsurprising. Its upper surfaces are a dull grey marked with dark irregular lines.

    female, underside
    (Photo: courtesy of Trevor Jinks, Upper Burnett, Queensland)

    But the undersides are strikingly patterned. They are pale grey, with black submarginal bands, bordered on the inside with red, and the forewings each have a large black spot and an orange patch.

    male, underside
    (Photo: courtesy of Nikita hosking, Goulburn, New South Wales)

    The males have comb-like antennae. The females have thread-like antennae. The moths usually rests with their wings outspread. The moths have a wingspan of about 4 cms.

    Crypsiphona ocultaria
    adult moth trying to read the time on a ladies wristwatch
    (Photo: courtesy of Ted Cadwallader, Swan Hill, Victoria)

    The eggs of this species are ovoid and green, and minutely pitted. They are laid irregularly along the edge of a leaf of the foodplant. They take about five days to hatch in captivity.

    Crypsiphona ocultaria
    eggs, magnified
    (Photo: courtesy of Steve Williams, Moths of Victoria: Part 4)

    The species is found over much of Australia, including:

  • Queensland,
  • New South Wales
  • Australian Capital Territory,
  • Victoria,
  • Tasmania,
  • South Australia, and
  • Western Australia.

    close-up of head of female
    (Photo: courtesy of Trevor Jinks, Upper Burnett, Queensland)

    Further reading :

    David Carter,
    Butterflies and Moths,
    Collins Eyewitness Handbooks, Sydney 1992, p. 195.

    Ian F.B. Common,
    Moths of Australia,
    Melbourne University Press, 1990, fig. 37.12, p. 372.

    Pat and Mike Coupar,
    Flying Colours,
    New South Wales University Press, Sydney 1992, p. 43.

    Edward Donovan,
    General Illustration of Entomology,
    An Epitome of the Natural History of the Insects of New Holland, New Zealand, New Guinea, Otaheite and other Islands in the Indian, Southern and Pacific Oceans,
    London (1803), p. 164, and also Plate, p. 162.

    Peter B. McQuillan, Jan A. Forrest, David Keane, & Roger Grund,
    Caterpillars, moths, and their plants of Southern Australia,
    Butterfly Conservation South Australia Inc., Adelaide (2019), p. 138.

    Peter Marriott,
    Moths of Victoria: Part 4,
    Emeralds and Allies - GEOMETROIDEA (B)
    Entomological Society of Victoria, 2012, pp. 30-31.

    Paul Zborowski and Ted Edwards,
    A Guide to Australian Moths,
    CSIRO Publishing, 2007, p. 139.

    Australian Butterflies
    Australian Moths

    (updated 29 June 2013, 14 May 2023)