Clouded sulphur and cloudless sulphur butterflies are two fascinating species often observed in gardens and natural habitats. Both butterfly species have distinct characteristics and appearances, which may leave nature enthusiasts curious about their differences.
The clouded sulphur butterfly, also known as the common sulphur, features yellow wings with a black border in males, while females have a duller hue with yellow spots on the black border. All adults have one black spot on each forewing and faint orange spots on the hindwings source.
On the other hand, the cloudless sulphur butterfly is a large yellow butterfly that does not have the distinct black border seen on clouded sulphurs. These butterflies can access nectar in tubular flowers that other butterflies can’t, with a preference for red flowers such as red morning-glory and scarlet sage source.
Identifying Clouded Sulphur and Cloudless Sulphur
- Males: bright yellow color
- Females: duller yellow, sometimes white
- Wing spans: 1.5 to 2 inches
- Males and females: bright yellow
- Larger size compared to Clouded Sulphur
- Wing span: 2.25 to 3.25 inches
- Single dark spot on each forewing
- Faint orange spots on hindwings
- No dark spots on wings
Clouded Sulphur (also known as Orange Sulphur):
- Male: lemon yellow with black border on wings
- Female: more white, black border with yellow spots
- Albino females: common, nearly white
- Consistent yellow throughout both genders
|Clouded Sulphur (Orange Sulphur)
|Bright yellow with black wing borders
|Bright yellow, larger size, no dark spots on wings
|Duller yellow, sometimes white
|Bright yellow, no dark spots on wings
|1.5 to 2 inches
|2.25 to 3.25 inches
|Forewing Dark Spot
|Faint orange spots
With the help of these characteristics and the comparison table, identifying Clouded Sulphur and Cloudless Sulphur butterflies becomes easier.
Habitats and Distribution
- Found throughout most of the mainland United States
- Primarily in eastern and southern portions of the western United States 1
- Widespread across North America
- Most common in disturbed open areas 2
- Prefers red flowers, e.g., red morning-glory, scarlet creeper, cypressvine, and scarlet sage 3
- Often seen in gardens and open areas 1
- Larval host plants belong to the genus Senna4
- Favors disturbed open areas, such as meadows and fields 2
- Usually found near its larval host plants, e.g., plants in the mustard and legume families 2
|Mainland US, eastern and southern parts
|Widespread across North America
|of the western US
|Gardens, open areas, red flowers
|Disturbed open areas, meadows, fields
|Mustard and legume families
Life Cycle and Host Plants
The life cycle of both the clouded and cloudless sulphur butterflies begins with egg-laying on host plants. Female butterflies typically lay eggs singly on the leaves or buds of their preferred host plants:
- Clouded Sulphur: Mostly partridge pea and alfalfa
- Cloudless Sulphur: Primarily plants in the Senna genus
Eggs are small, with clouded sulphur eggs appearing as greenish-white and cloudless sulphur eggs as pale yellow.
After hatching, the caterpillars of both species feed on their host plants. Caterpillars have different appearances:
- Clouded Sulphur: Green with yellow and black markings, length up to 2.5 cm
- Cloudless Sulphur: Bright green to yellowish-green with blue-black bands, length up to 4 cm
Caterpillars of both species have few natural predators due to the toxins they accumulate from their host plants, but they may still fall prey to birds, parasitic wasps, or spiders.
Chrysalis and Pupae
Once the caterpillars have reached their final instar, they form a chrysalis or pupa. While in this stage, they undergo metamorphosis to develop into adult butterflies:
- Clouded Sulphur: Green or brown chrysalis, often blending in with surrounding foliage
- Cloudless Sulphur: Pale green to brown chrysalis, usually attached to Senna plants
The chrysalis stage lasts for approximately 10 days to 2 weeks.
Adult butterflies of both species are primarily active from spring through fall, with a peak in their populations during fall migration. They can be distinguished by color and size:
- Clouded Sulphur (Coliadinae): Wingspan of 3.2 cm, pale yellow to white (female) or golden-yellow with black borders (male)
- Cloudless Sulphur (Phoebis sennae): Wingspan of 6 cm, bright yellow (male) or pale yellow/white (female)
Adult butterflies feed on nectar from tubular flowers, such as those from orange, senna, and other host plants.
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – Australian Caper Gull
Australian Caper Gull
Mon, Nov 3, 2008 at 1:17 AM
Had my first photo opportunity with this Australian Caper Gull (Cepora perimale scyllara ) when it got interested in the Basil in my garden. There are a few of them around but they are usually very flighty and hard to get close to. Hope you like it.
Once again, thanks for contributing a new species to our expanding selection of Bugs Down Under. We are linking to a James Cook University website with additional information on the Australian Caper Gull, a butterfly in the family Pieridae that includes Whites and Sulfurs.
Letter 2 – Chocolate Albatross from Asia
March 1, 2012
Another of Carol’s butterflies is a member of the family Pieridae, the Whites and Sulfurs, and we quickly identified it on Sambui Butterflies as a Chocolate Albatross, Appias lyncida vasava. This individual is also mud puddling. Sambui Butterflies lists the range as: “Sri Lanka, India and Burma through the Malay Peninsular. Other subspecies throughout the Oriental Region)” and we are still waiting for information from Carol on the location of this sighting. According to the Butterflies of Malaysia website: “Males congregate, sometimes in groups of 50 or more, to imbibe mineralised moisture from damp patches of ground in full sunlight. They are strongly attracted to urine soaked soil, and to mineral-rich sand on recently exposed river beaches in heavily forested areas. If disturbed they fly up in a swirling mass, but resettle to resume feeding at the same spot within a few minutes. Females are normally only seen when flying in search of egg-laying sites within the forest.”
Thanks for identifying the butterfly!
The River Ou in Laos was where the riverside photos were taken. We were between Muang La and Luang Prabang.
The caterpillar suspended across a very large open space was probably on a low mountain near a temple near Muang La, Laos.
The other photos were near the Queen’s Garden in a mountainous area near Chiang Rai or Chiang Saen in Thailand.
Where is the butterfly site you are hosting?
Letter 3 – Dwarf Yellow Sulphur
Subject: Dwarf Yellow Sulphur Butterfly
Location: 36 degrees 24’ 57.11”N; 88 degrees 12’ 21.94” W [Tennessee]
September 19, 2012 8:23 pm
I think my previous attempt to send to you did not work. If it did, guess you can delete one of the messages. I believe that the two pictures here are Dwarf Yellow Sulphur Butterflies. They are really small – probably less than an inch from body to wingtip. There were at least a dozen or more in our field late this afternoon (Sept. 19, 2012). We are in Buchanan, TN which is in the northeastern corner of west TN (Kentucky Lake is our county’s eastern border and Kentucky is our northern border). The butterflies did not seem to be looking for flowers – the two here were on blades of grass and some even lit on piles of dead grass left from haying last month. I did not see this butterfly on your site nor on Bug Guide, but based my ID on National Audubon Society Field Guide to Butterflies.
Signature: Mary Ann
Hi Mary Ann,
We could not find any evidence that you sent this submission twice. We are thrilled to get your lovely photos of a Dwarf Yellow Sulphur, Nathalis iole, which BugGuide calls the Dainty Yellow and elaborates: “Resident in Guatemala north to peninsular Florida and the Southwest. Cannot survive cold winters, therefore every summer re-colonizes through the Great Plains to southeast Washington, southeast Idaho, Wyoming, and Minnesota.” The habitat is listed as: “Open, dry places including coastal flats, weedy fields, grasslands, road edges, meadows, and hillsides” where it feeds on “Dogweed, marigold and other asters.” Known as North America’s smallest Sulphur, this is a new species for our website.
Letter 4 – Female Orange Sulphur
October 12, 2009
Found in the tall bluestem prairie, October 5, 2009
Goose Lake Prairie, Illinois
This is a female Orange Sulphur, Colias eurytheme. The female can be distinguished by the spots in the black wing borders. The caterpillars feed on clover, alfalfa and other legumes. You can search BugGuide for more information on the species.
Letter 5 – Female Sulphur Butterfly
Subject: Beautiful butterfly or moth?
Location: Bellevue NE
September 8, 2012 7:01 am
This was taken in my son’s garden. It’s an 18’x13’ heart shape dedicated to his heart donor.
We live in Bellevue, Nebraska (Omaha) just one mile from the Missouri River.
Never seen it again.
Signature: Eric Zeitner
What a marvelous idea for a garden dedication. Congratulations on your son receiving a donor heart. This lovely butterfly is a female Sulphur, most likely an Orange Sulphur, Colias eurytheme, also known as the Alfalfa Sulphur. Because or the light shining through the wings, the distinctive orange color is visible which is a clue to the species, and the lighter spots in the black wing borders indicates that she is a female. You can read more about the Orange Sulphur on BugGuide.
Letter 6 – Leventine Marbled White from Israel
Butterfly from Israel
April 12, 2010
Me again from Israel, and still in love with your website!
On my latest hiking trip, this time to Eastern Samaria (north-east of Jerusalem, Israel) on April 9-10, 2010, I saw and photographed loads of bugs. Everything is waking up after the winter, the hills are green and alive!
My first bug is this Melanargia titea titania, who was patiently waiting for me to get my camera out.
Eastern Samaria, Israel