Woodlands Historic Park Insects

Stencilled Hairstreak (Jalmenus ictinus) at Woodlands Historic Park
Stencilled Hairstreak Butterfly, late January. Photo by Andrew Allen
Jalmenus ictinus feeding at Woodlands Historic Park
Feeding on a flower of Sticky Everlasting, mid March. The blue colouring on the top of the wings seems to be only visible if light hits the wing at an acute angle, otherwise they just appear brown.
Jalmenus ictinus mating at Woodlands Historic Park
Mating, mid March
Jalmenus ictinus pupae at Woodlands Historic Park
Pupae, mid March. Guardian ants have been chased off by the photographer
Larva of Stencilled Hairstreak (Jalmenus ictinus) at Woodlands Historic Park
Caterpillar, late February.

Wingspan: male 36mm, female 42 mm

The caterpillars of this butterfly feed on a number of species of wattles, including Lightwood and Black Wattle. However we have only seen caterpillars and pupae on Black Wattle and adults on or around Black Wattle or feeding on flowers, as shown above.

Caterpillars and pupae of the Stencilled Hairstreak are protected from parasites and predators by ants, and in return supply the ants with food in the form of a solution of sugars and amino acids. The ants are essential to the survival of the caterpillars, but neither the caterpillars nor the wattles are essential to the survival of the ants, so it is just by chance that the ants will occur in the right place to allow the butterflies to breed successfully. (I infer this from a paper by Smiley and others (1988) about the closely related Imperial Hairstreak.) According to Field in "Butterflies: Identification and life history" few colonies are known to remain in Victoria. The population in Woodlands Historic Park seems to be small.

Classification

from Australian Faunal Directory

Order Lepidoptera - Moths and Butterflies, 10855 named species in Australia
Family LYCAENIDAE - Blues, Coppers and Hairstreaks, 157 species in Australia
Genus Jalmenus (11 Species in Australia)
Species Jalmenus ictinus

References