The clouded sulphur, also known as common sulphur, (Colias philodice) is a butterfly that belongs to the family Pieridae, which includes other yellows, whites and sulphurs. The clouded sulphur is native to Canada and can be found throughout North America. The adults are best adapted to open areas such as moist meadows, lawns, and alfalfa and clover fields, where they feeds on nectar of various plants, including alfalfa, clovers, milkweed, dandelions, thistles, goldenrods, common selfheal, wild teasel. Adults also extract moisture and minerals from mud puddles or animal excrements. The larvae feed on members of the legume family.

The clouded sulphur produces several generations each year. To mate, the male typically flies towards the female and after the female lands the male will repeatedly hit his wings against the female's body. This results in pheromones being released. The female may then lower her abdomen and mating will occur. Their eggs are cream to yellow in colour when first layed, turning red shortly after, and hatching within about 5 days.. The larvae are green with light stripes on their sides and a dark stripe on the back. They also have a smooth texture. The larvae will construct a chrysalis that is green and pointed on both ends where they will remain overwinter. . The adults have yellow wings though this varies throughout the season, with them being green-yellow in the spring and fall, whereas they are yellow in the summer. Their wings have a black border on the upper side. This feature on the females is interspersed with yellow spots. The underside of their hindwings have a silver spot surrounded by two red rings. Some females can be white. Adults live for 2 to 7 days.

Clouded sulphurs can hybridize with orange sulphurs (Colias eurytheme) as they are closely related species. This happens when the females are young (less than one hour old) and are unable to distinguish between the pheromones of the two species, resulting in offspring that may be sterile.

Posted on December 23, 2023 07:07 PM by kiarra13