Large Marble

Scattered white scales in forewing black bar. Black pattern on tip of upperside of forewing. Dense green marbling on underside of hindwing. Males patrol valleys and hillsides for females. Eggs are laid singly on unopened flower buds; caterpillars eat flowers and fruits. The Large Marble is found throughout most of western Canada as far north as treeline. It is absent from the west coast (extinct on southern Vancouver Island) and from the open prairie regions of southern Saskatchewan and Manitoba. Its range extends eastward into Ontario as far as Manitoulin Island.

This is the largest (wingspan: 30 to 48 mm) of the five Large Marble found in Canada. The underside of the hindwing usually has more white shading than green, with the white shading forming large irregular spots that partially fuse together through the reticulate green pattern; the veins are usually lined with yellow, and this extends through the green pattern. On the upper surface of the forewing the dark discal spot in the middle of the leading edge of the wing is black, with an extensive dusting of white scales (best seen with a microscope or a 15x hand lens).

The discal spot of Large Marble is narrow in males, with the apex (projecting towards the middle of the wing) pointed or rounded; in females it tends to be broader, with the apex squared off, but the upper surface of the hindwing often has a slightly yellow cast in females, unlike the other marbles.

Posted in: L,Large Marble,Pieridae