|Male P. s. sennae, Tobago|
|Female P. s. sennae, Tobago|
Three, see text
Phoebis sennae, the cloudless sulphur, is a mid-sized butterfly in the family Pieridae found in the Americas. There are several similar species such as the yellow angled-sulphur (Anteos maerula), which has angled wings, statira sulphur (Aphrissa statira), and other sulphurs, which are much smaller.
Their range is wide, from South America to southern Canada, in particular southwestern Ontario. They are most common from Argentina to southern Texas, Georgia, and Florida, but are often visitors outside this range becoming more rare further north.
The common habitats of this butterfly are open spaces, gardens, glades, seashores, and watercourses.
The adult butterfly feeds on nectar from many different flowers with long tubes including cordia, bougainvillea, cardinal flower, hibiscus, lantana, and wild morning glory. The larvae also feed on sennas and partridge peas.
The breeding season is dependent on the climate of the area, from midsummer to fall in the cooler areas, to year-round where the climate is warmer.
The cloudless sulphur starts off as a pitcher-shaped white egg. Eventually it will turn to a pale orange. The egg stage lasts six days.
Once the egg hatches, a caterpillar emerges that is yellow to greenish, striped on sides, with black dots in rows across the back. The host plant may be partridge pea (Chamaecrista cinerea), sennas (Senna), clovers (Trifolium), or other legumes (Fabaceae). The caterpillar will usually grow to a length between 41 and 45 mm (1.6 and 1.8 in).
The caterpillar will form a chrysalis that is pointed at both ends and humped in the middle. The chrysalis will be either yellow or green with pink or green stripes. From the chrysalis comes a medium-sized butterfly (55–70 mm (2.2–2.8 in)) with fairly elongated but not angled wings.
The male butterfly is clear yellow above and yellow or mottled with reddish brown below and the female is lemon yellow to golden or white on both surfaces, with varying amounts of black spotting along the margin and a black open square or star on the bottom forewing. Wingspan: 63–78 mm (2.5–3.1 in).
Yellow version of caterpillar feeding on senna tree, Vista, California
Male P. s. marcellina
in Panama, some males are unmarked
- P. s. amphitrite (Feisthamel, 1839) – Chile
- P. s. sennae or P. s. eubule – Jamaica, South Carolina, Kansas, Virginia, Florida, Cuba
- P. s. marcellina (Cramer, ) – Mexico, Uruguay, Galapagos, Suriname, Honduras, Brazil, Argentina, Bolivia, Peru
- "NatureServe Explorer 2.0 Phoebis sennae Cloudless Sulphur". explorer.natureserve.org. Retrieved 3 October 2020.
- Walker, A. (2020). "Phoebis sennae". IUCN Red List of Threatened Species. 2020: e.T173004589A173004624. doi:10.2305/IUCN.UK.2020-3.RLTS.T173004589A173004624.en. Retrieved 18 November 2021.
- Cloudless Sulphur, Butterflies of Canada
- C., Minno, Marc (2010). Butterflies of central florida : a guide to common and notable species. [Place of publication not identified]: Quick Reference Pub Inc. ISBN 978-0982885604. OCLC 943772335.
- Lady Bird Johnson Wildflower Center Native Plant Information Network: Senna hebecarpa
- Clark, Dale. "Phoebis sennae". Dallas County Lepidopterists' Society. Retrieved 2008-07-21.
- Phoebis sennae, funet.fi