U.S. Virgin Islands Territorial Insect
Cloudless Sulfur Butterfly (common name)
Phoebis sennae (scientific name)
This large, colorful butterfly is named for its sulphur-colored wings. The wings of the male cloudless sulphur butterfly are light yellow above and a mottled yellow or reddish brown below. The female’s wings are lemon yellow, golden, or white with black eye spots on the upper wings. Both sexes have two small irregular silver splotches on the underside of their hindwings. While the U.S. Virgin Islands has no official insect symbol, this striking butterfly remains in the territory year-round and is an appropriate symbol of the land's natural beauty.
Wingspan: 2.2–2.75 in (5.5–7 cm)
Total Length: 1.4–2 inches (3.5–5 cm)
Larvae: Initially green while they are eating the green leaves of cassia plants and then yellow-green with narrow yellow stripes on the sides and black dots in rows on its back after eating the yellow flowers of the plant. The caterpillar grows to a length of 1.63–1.75 in (3.8–4.3 cm).
From two to three days to a maximum of 24 days.
Open, sunny areas including fields, gardens, agricultural fields, seashores, and along rivers and other bodies of fresh water.
Range: Continent-wide distribution in the Americas, from southern Canada to Argentina.
Flight period: Year-round in the U.S. Virgin Islands and other temperate climates. In the northern part of its range the cloudless sulphur will migrate to southern Canada to breed and then return to the Midwest and South in the U.S. to overwinter as cooler autumn weather approaches.
Conservation status: Common and widespread throughout its range and receives no special protection. Northern range is shrinking and the butterflies are now rare north of southern Texas and Florida.
Males exhibit a vigorous, searching flight pattern as they pursue females. The males also produce pheromones to attract the female during courtship. If the female wants to reject the male’s advances, it goes spiraling upward into the air, and the male, after a few attempts, gives up and goes in search of a more willing mate.
Cloudless sulphurs will roost on or under the leaves of plants that are as the same color as their wing color. Females lay eggs on young leaves or the flower buds of host plants. The cloudless sulphur caterpillar builds a tent on the undersides of the leaves of its host plants where it stays during the day. The caterpillar forms a chrysalis that is thick in the middle and pointed at both ends. It overwinters in this pupa, which is yellow or green in color with pink or green stripes.
Adults: Nectar of flowers like bougainvillea, hibiscus, lantana, azalea, red pagoda, petunia, sage, and morning glory.
Larvae: Clovers, wild indigo, wild pea, trefoil, lupine, alfalfa, and cassia.
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|Author: World Trade Press|