Cloudless Sulphur Host Plant: Essential Guide for Gardeners

Cloudless sulphur butterflies are a delightful sight in gardens, known for their vibrant yellow and various green hues. These butterflies not only enhance the beauty of the garden, but also act as pollinators for different plants. As a gardener or a nature enthusiast, it is essential to be informed about cloudless sulphur host plants, so you can create a haven for these beautiful creatures.

Among various plants that can be potential host plants for cloudless sulphur butterflies, the Senna genus plays a crucial role. These plants serve as an ideal breeding ground, providing all the necessary nutrients for their offspring – from the egg stage to the fully grown caterpillar. By incorporating suitable host plants in your garden, you’ll witness the fascinating life cycle and transformation of these magnificent butterflies.

For instance, the cloudless sulphur’s larval host belongs to the Senna genus, where caterpillars feed and grow, eventually turning into adults. Some popular host plants include candlestick plant (Senna alata) and wild senna (Senna hebecarpa). Providing a range of host plants will attract cloudless sulphur butterflies, contributing to a thriving ecosystem in your garden.

Cloudless Sulphur: An Overview

Species and Characteristics

The Cloudless Sulphur (Phoebis sennae) is a common and eye-catching yellow butterfly. Some key features include:

• Wingspan: 2 to 2¾ inches (5.4 – 7.0 cm)
• Males: lemon yellow with no markings
• Females: yellow or white, with irregular black borders and a dark spot on the upper forewing
• Both sexes: Lower surface of hindwing has 2 pink-edged silver spots

This butterfly belongs to the Pieridae family of butterflies, which are known for their bright colors.

Habitats and Distribution

The Cloudless Sulphur can be found throughout most of the mainland United States. Their habitats include:

• Eastern United States
• Southern portions of the western United States
• Occasionally spotted as far north as Canada

They are particularly attracted to gardens and open areas, where their host plants are commonly found. These butterflies play a vital role in pollinating plants in their habitat.

The Life Cycle of Cloudless Sulphur

Caterpillar Stage

The life of a cloudless sulphur butterfly begins as a tiny caterpillar. Cloudless sulphur caterpillars feed on plants from the Senna genus, making these plants their primary host plants.

Characteristics of cloudless sulphur caterpillar:

• Green or yellow-green in color
• Prominent yellow stripe down the side of the body

As the caterpillar grows, it sheds its skin, going through multiple instar stages before reaching the chrysalis stage.

Chrysalis Stage

Once the caterpillar has grown sufficiently, it enters the chrysalis stage. It attaches itself to a plant stem, secreting a silk-like substance to form a protective casing.

Key features of the chrysalis:

• Color varies, usually matching the surrounding environment for camouflage
• Hangs vertically, often on the host plant itself

This stage is all about transformation, as the caterpillar morphs into an adult butterfly within the chrysalis. This process can take about 9 to 12 days.

Adult Butterfly Stage

After emerging from the chrysalis, the cloudless sulphur becomes a stunning adult butterfly. The adult cloudless sulphur has a wingspan of 2 to 2¾ inches (5.4 – 7.0 cm).

Distinguishing features of adult cloudless sulphur:

• Males have a lemon-yellow color, usually without any markings
• Females can be yellow or white, with dark borders and spots

As adult butterflies, they feed on nectar from various flowers. Adult cloudless sulphurs are strong fliers, often traveling long distances to find suitable host plants. Adult butterflies lay their eggs on the host plants, starting the cycle over again.

Host Plants

Native Host Plants in North America

The cloudless sulphur butterfly, scientifically known as Phoebis sennae, primarily relies on native plants for its larval host plants. Some examples of native host plants include:

• Partridge Pea (Chamaecrista fasciculata): Attracts the cloudless sulphur butterfly and provides sustenance for caterpillars.
• Sensitive Pea (Chamaecrista lineata var. keyensis): Another native host plant that supports the butterfly’s growth.

These native host plants not only support the life cycle of the cloudless sulphur, but also contribute to the local ecosystem.

Introduced Host Species

Among the introduced host species favored by cloudless sulphur caterpillars, the Cassia plant stands out. This genus of plants, closely related to Senna, includes several species that aid in the growth and development of the cloudless sulphur butterfly. For example:

• Coffeeweed (Senna obtusifolia): An introduced host plant that provides a suitable environment for caterpillars to thrive.

By becoming familiar with these host plants, you can make informed choices when planting in your garden or supporting local ecosystems, ensuring a healthy environment for cloudless sulphur butterflies and other beneficial species.

Nectar Plants and Feeding

Native Nectar Plants

Cloudless sulphur butterflies are often found in areas with native nectar plants. Some examples of native nectar plants ideal for them include:

• Red morning-glory (Ipomoea coccinea)
• Scarlet creeper (Ipomoea hederifolia)
• Cypressvine (Ipomoea quamoclit)
• Scarlet sage (Salvia coccinea)

These plants provide essential nectar for the butterflies to feed on and thrive. source

Flower Preferences

The cloudless sulphur butterflies are known for their preference for red-colored flowers. They generally prefer tubular flowers, which they can access due to their long proboscis. This unique adaptation allows them to reach the nectar in the flowers that other pollinators, like bees, may not be able to access. source

Table 1: Comparing flower preferences of cloudless sulphur butterflies and bees

Their long proboscis also helps these butterflies drink nectar from a variety of nectar plants, providing them with an advantage in their search for food resources. Overall, the selection of nectar plants and their feeding preferences contribute significantly to the flourishing of cloudless sulphur butterflies in their environment.

Migration

Seasonal Movements

The cloudless sulphur butterfly is known for its seasonal migration patterns. These yellow butterflies are commonly seen in the southern United States and can migrate considerable distances during the fall. Some move from the mainland to warmer regions like Florida and the Florida Keys, searching for suitable host plants such as the sensitive pea (Senna ligustrina), which is abundant in this area.

Long Distance Migration

The cloudless sulphur butterflies can also undergo long distance migrations. For instance, some populations have been found to travel even as far as Argentina, covering thousands of miles in search of appropriate host plants. Despite the impressive nature of their migrations, little is still understood about the exact mechanisms involved in their long-distance journeys.

During migration, cloudless sulphurs exhibit some fascinating features:

• They often migrate in groups
• Migrations typically occur during the day
• Cloudless sulphurs are quick and agile fliers, which aids in their long journeys

Comparison Table: Seasonal vs. Long Distance Migration

Note that both seasonal and long distance migrations serve important functions for the cloudless sulphur butterfly. By understanding their migration patterns, we can better appreciate the resilience and adaptability of these remarkable creatures.

Ecological Interactions

Predators and Defense Mechanisms

In their natural habitat, cloudless sulphur butterflies (Phoebis sennae) are preyed upon by various predators, including birds and other insects. As members of the Pieridae family, they have developed a few defense mechanisms to evade these dangers:

• Camouflage: Their yellow coloration helps them blend in with their surroundings, especially among yellow flowers and foliage.
• Toxicity: Caterpillars may store toxic compounds from their host plants, making them unappetizing or harmful to predators.

Pollination and Plant Relationships

Cloudless sulphur butterflies play an important role in pollination, particularly for plants in the Senna genus. When they visit flowers to feed on nectar, they inadvertently transfer pollen between plants, contributing to reproduction.

• Host plant relationships:
  • Preferred host plants: Species within the Senna genus
  • Secondary host plants: Other species in the Fabaceae family

As members of the Lepidoptera order, related to both butterflies and moths within the Coliadinae subfamily, cloudless sulphurs share some common traits with their close relatives and cohabitants in their ecosystem:

By understanding the ecological interactions, including predator defense mechanisms and pollination habits of the cloudless sulphur butterfly, we can contribute to conservation efforts, habitat sustainability, and balanced ecosystems in areas where these butterflies are commonly found.

Conservation and Impact

Population Status

The cloudless sulphur butterfly is a common species found predominantly in the eastern United States, southern portions of the western United States, and as far north as Canada ¹. In the West Indies, the population status of this butterfly is less well-known, but it is believed to thrive there due to the presence of native host plants in the region ².

Human Influence

Human influence plays a significant role in the conservation and impact of the cloudless sulphur butterfly. The availability of native host plants is an essential factor for the survival and reproduction of these butterflies. Examples of such plants include the Senna genus, which the cloudless sulphur butterfly’s scientific name, Phoebis sennae, references ³.

However, the introduction of non-native host species can have both positive and negative impacts on the cloudless sulphur butterfly population:

Pros:

• Increased host plant availability may create more habitat opportunities for the butterfly population to expand.

Cons:

• Introduced host species could potentially outcompete or otherwise negatively affect native host plants, ultimately impacting butterfly populations.

Comparison Table of Native and Introduced Host Plants

In conclusion, conservation efforts for the cloudless sulphur butterfly must consider both the native host plants and human influence. Providing habitat through maintaining native host plants, minimizing the impact of introduced species, and spreading awareness about this beautiful butterfly species is crucial for its continued existence in the wild. ².

Reader Emails

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 – Probably Orange Sulphur: White Female Form

Pink-edged Sulphur butterfly?
Bugman,
I took this picture of what I think is a Pink-edged Sulphur. I never saw it with it’s wings open. So, I don’t know for sure if it is. Could it be a Common or Clouded Sulphur? I took this picture a couple of months in southern Indiana. I noticed that the Pick-edged Sulphur usually is found further north of this area. Can you tell by these photographs which one it is? Thanks,
Patrick Crone

Hi Patrick,
We actually believe this is an Orange Sulphur, Colias eurytheme, which has a white female form. There is a photo posted to BugGuide taken in Illinois in October that looks virtually identical to your photo. Sulphurs in the genus Colias are often difficult to distinguish from one another.

Letter 2 – Puddling Sulphur Butterflies

lime green butterflies in Missouri
December 17, 2009
Can you tell me anything about these beautiful butterflies? I’ve lived in Missouri all of my life and have not seen them before, or since, I took these photos.
Catherine Dukleth
Clarence Cannon Nat’l Wildlife Refuge – Missouri

Hi Catherine,
We were going to write that Missouri is sure warm this time of year until we realized your photos are dated from September.  The larger butterflies in your awesome photo are Cloudless Sulphurs, Pheobis sennae, a tropical species that flies year round in the southern United States where it has naturalized.  It has also naturalized in Southern California, no doubt due to the cultivation of cassia, the larval food plant.  According to BugGuide, the range is the “Southern United States; often migrates north in late summer/fall, sometimes reaching northern states and southern Ontario (see US distribution map).  Permanent resident in the tropics, occurring south to the tip of South America.”  The smaller butterflies in your photos are probably members of the genus Colias, but we cannot identify the exact species without a closer view.  Several species, including the Clouded Sulphur and the Orange Sulphur,  fly in your area from spring through fall, and the caterpillars feed on clover and other legumes.  Your photos depict mud puddling or a puddling party where large aggregations of butterflies gather at mud or wet soil to drink.  They obtain nutrients including salts and amino acids from the activity.  Wikipedia has a page on mud puddling.

THANKS!!!!!!!!!!  THAT’S AWESOME!!!  HAVE A GREAT HOLIDAY SEASON!!!
CATH

Letter 3 – Salmon Caper Butterfly from Jordan

Subject:  Butterfly or moth found in amman
Geographic location of the bug:  Amman, jordan
Date: 08/31/2019
Time: 06:27 PM EDT
Your letter to the bugman:  Hello, i found this dead butterfly or moth and was just wondering what its name was. I tried to find it online but nothing came up.
How you want your letter signed:  Raya

Dear Raya,
We identified this Salmon Caper Butterfly, Madais fausta fausta, on image 1g of The Butterflies of Jordan where it states:  ” The Salmon Caper Butterfly is a rather migratory species with a distribution con- fined to the Jordan Valley and the upper Mediterranean zone. … It seems that it has two broods, one in spring and another towards the end of July.“

Letter 4 – Senna Sulphur

Subject: Cloudless Sulphur Butterfly?
Location: Coryell County, Texas
November 21, 2013 11:42 am
Is this a female Cloudless Sulphur Butterfly?
Bug Guide reference: http://www.dallasbutterflies.com/Butterflies/html/sennae.html
I don’t understand the clouded/cloudless designation differences.
I planted more of the Autumn Sage this fall; it’s a butterfly magnet, and a drought-resistant native plant.
Signature: Ellen

Hi again Ellen,
BugGuide sometimes explains the meaning of the name, but in the case of the Cloudless Sulphur, they do not.  Charles Hogue, in his book Insects of the Los Angeles Basin, referred to this species, Phoebis sennae, as the Senna Sulphur, which is a reference to the food plant of the caterpillar.  We always thought that “cloudless” referred to the male of the species having no markings. 

Letter 5 – Southern Dogface and Sulphur

Subject: Orange Sulfur, Perhaps
Location: Coryell County, central Texas
January 21, 2013 1:55 am
These lovely butterflies were enjoying the same tiny, white flowers as many others today. I think they may be Orange Sulfurs. Several flew in pairs. Beautiful weather, sun and warm temps this afternoon.
Signature: Ellen

Hi Ellen,
The smaller, blurry butterfly in the image with two individuals is some species of Sulphur, possibly and Orange Sulphur, but the larger butterfly and the one in the photo alone is a Southern Dogface, a species not very well represented on our site.  According to BugGuide, it can be identified because the:  “pattern of the upper forewing resembles a yellow “dog face” bordered by black, with a black circle forming the eye.”  Since the Southern Dogface in your photo is backlit, the pattern on the dorsal wing surface shows through nicely.

Letter 6 – Southern Dogface Butterfly

Subject: Southern Dogface Butterfly?
Location: Coryell County, Texas
November 19, 2013 1:33 pm
Hello,
Here is a beautiful butterfly, and I think it might be a Southern Dogface Butterfly. You identified one for me last spring, thank you!
I took photo after photo, trying to get an open-winged shot. I can’t tell you how many photos I took of the brick wall, the house eaves, the fence, the mulch, the grass and the flowers (without capturing the elusive flying Dogface), when I finally got a decent shot. Hooray! It’s blurry but distinguishable.
This butterfly stayed near the garden for the half-hour I was there. After feeding, the clever creature rested on the crepe myrtle leaves, only resting on the yellow leaves, never the green leaves. Camouflage?
It fluttered around other yellow butterflies its size that visited the garden, but I don’t know if it was guarding or courting. Once, three butterflies were circling each other. The other two flew off after feeding briefly.
I have photos of one of the other butterflies if you are interested. It may be a female Southern Dogface, but I’m not sure. I’m pretty sure it’s a Sulphur in any case.
Thank you for all of your help!
Thank you!
Signature: Ellen

Hi Ellen,
We got a bit of a chuckle at your attempt to photograph this Southern Dogface Butterfly, Zerene cesonia.  We went through a similar attempt to capture a good photograph of a Western Tiger Swallowtail in our our garden several years ago.  One of the beauties of digital photography over traditional analog photography is that it is much easier to keep shooting and shooting until you get a decent image.  As educators, we still believe that a firm foundation in analog photography makes better photographers despite the fact that they will not be working in analog professionally.  We are very pressed for time due to work obligations, and though you sent several submissions our way, we might not get them all posted this morning.

Letter 7 – Sulpher Chrysalis

Do you recognize this chrysalis?
Charlene

Charlene,
The orneriness in us wants to just reply “yes” and leave it at that, but we do not have a representative image on the site and are happy to have your Sulphur Butterfly Chrysalis. Since you did not provide us with a location and since your image is cropped oddly, we are not sure of the species. If you are in the American Southwest, it is probably a Senna Sulphur, Phoebis sennae, that feeds on cassia.

Great new image & a friend
Yes, sorry. My husband noticed I had supplied NO info. I’ll try and take a better picture. I am in Houston. And I do have a cassia in the backyard. Glad to know it is doing it’s job. I considered taking the plant out because it is quite ugly. I tried to trim it and did a very poor job. I’ll keep it around now. Thanks for the info. It was a rather ugly looking . How do such things turn into beauties??? By the way, I loved your sight and will be sure to pass it on to my friends!! This is really cool! I went outside to take a better picture of the chrysalis that I sent yesterday and some information on it and look what I found!! How strange that they crawled to the same place to “hang out” together!!!! Their host plant is across the yard. I live in Houston and would love an identification of these beauties. Thank you,
Charlene

Hi again Charlene,
We are certain you have a Senna Sulphur caterpillar and chrysalis. Wait for the gorgeous clear yellow butterflies to emerge and send a photo of them as well. They are strong fliers and difficult to approach.

Letter 8 – Sulphur Butterfly

butterfly
Hello again Bugman,
I like this subject better than the roach picture I just sent. What kind of pretty butterfly is this? We live in NC.
Nancy

Hi Nancy,
This is one of the Sulphur Butterflies in the genus Colias. It appears as though yellow spots in the black wing border are visible through the wings, indicating she is female, and the slight orange color indicated most probably the Alfalfa Butterfly, Colias eurytheme.

Reader Emails

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 – Probably Orange Sulphur: White Female Form

Pink-edged Sulphur butterfly?
Bugman,
I took this picture of what I think is a Pink-edged Sulphur. I never saw it with it’s wings open. So, I don’t know for sure if it is. Could it be a Common or Clouded Sulphur? I took this picture a couple of months in southern Indiana. I noticed that the Pick-edged Sulphur usually is found further north of this area. Can you tell by these photographs which one it is? Thanks,
Patrick Crone

Hi Patrick,
We actually believe this is an Orange Sulphur, Colias eurytheme, which has a white female form. There is a photo posted to BugGuide taken in Illinois in October that looks virtually identical to your photo. Sulphurs in the genus Colias are often difficult to distinguish from one another.

Letter 2 – Puddling Sulphur Butterflies

lime green butterflies in Missouri
December 17, 2009
Can you tell me anything about these beautiful butterflies? I’ve lived in Missouri all of my life and have not seen them before, or since, I took these photos.
Catherine Dukleth
Clarence Cannon Nat’l Wildlife Refuge – Missouri

Hi Catherine,
We were going to write that Missouri is sure warm this time of year until we realized your photos are dated from September.  The larger butterflies in your awesome photo are Cloudless Sulphurs, Pheobis sennae, a tropical species that flies year round in the southern United States where it has naturalized.  It has also naturalized in Southern California, no doubt due to the cultivation of cassia, the larval food plant.  According to BugGuide, the range is the “Southern United States; often migrates north in late summer/fall, sometimes reaching northern states and southern Ontario (see US distribution map).  Permanent resident in the tropics, occurring south to the tip of South America.”  The smaller butterflies in your photos are probably members of the genus Colias, but we cannot identify the exact species without a closer view.  Several species, including the Clouded Sulphur and the Orange Sulphur,  fly in your area from spring through fall, and the caterpillars feed on clover and other legumes.  Your photos depict mud puddling or a puddling party where large aggregations of butterflies gather at mud or wet soil to drink.  They obtain nutrients including salts and amino acids from the activity.  Wikipedia has a page on mud puddling.

THANKS!!!!!!!!!!  THAT’S AWESOME!!!  HAVE A GREAT HOLIDAY SEASON!!!
CATH

Letter 3 – Salmon Caper Butterfly from Jordan

Subject:  Butterfly or moth found in amman
Geographic location of the bug:  Amman, jordan
Date: 08/31/2019
Time: 06:27 PM EDT
Your letter to the bugman:  Hello, i found this dead butterfly or moth and was just wondering what its name was. I tried to find it online but nothing came up.
How you want your letter signed:  Raya

Dear Raya,
We identified this Salmon Caper Butterfly, Madais fausta fausta, on image 1g of The Butterflies of Jordan where it states:  ” The Salmon Caper Butterfly is a rather migratory species with a distribution con- fined to the Jordan Valley and the upper Mediterranean zone. … It seems that it has two broods, one in spring and another towards the end of July.“

Letter 4 – Senna Sulphur

Subject: Cloudless Sulphur Butterfly?
Location: Coryell County, Texas
November 21, 2013 11:42 am
Is this a female Cloudless Sulphur Butterfly?
Bug Guide reference: http://www.dallasbutterflies.com/Butterflies/html/sennae.html
I don’t understand the clouded/cloudless designation differences.
I planted more of the Autumn Sage this fall; it’s a butterfly magnet, and a drought-resistant native plant.
Signature: Ellen

Hi again Ellen,
BugGuide sometimes explains the meaning of the name, but in the case of the Cloudless Sulphur, they do not.  Charles Hogue, in his book Insects of the Los Angeles Basin, referred to this species, Phoebis sennae, as the Senna Sulphur, which is a reference to the food plant of the caterpillar.  We always thought that “cloudless” referred to the male of the species having no markings. 

Letter 5 – Southern Dogface and Sulphur

Subject: Orange Sulfur, Perhaps
Location: Coryell County, central Texas
January 21, 2013 1:55 am
These lovely butterflies were enjoying the same tiny, white flowers as many others today. I think they may be Orange Sulfurs. Several flew in pairs. Beautiful weather, sun and warm temps this afternoon.
Signature: Ellen

Hi Ellen,
The smaller, blurry butterfly in the image with two individuals is some species of Sulphur, possibly and Orange Sulphur, but the larger butterfly and the one in the photo alone is a Southern Dogface, a species not very well represented on our site.  According to BugGuide, it can be identified because the:  “pattern of the upper forewing resembles a yellow “dog face” bordered by black, with a black circle forming the eye.”  Since the Southern Dogface in your photo is backlit, the pattern on the dorsal wing surface shows through nicely.

Letter 6 – Southern Dogface Butterfly

Subject: Southern Dogface Butterfly?
Location: Coryell County, Texas
November 19, 2013 1:33 pm
Hello,
Here is a beautiful butterfly, and I think it might be a Southern Dogface Butterfly. You identified one for me last spring, thank you!
I took photo after photo, trying to get an open-winged shot. I can’t tell you how many photos I took of the brick wall, the house eaves, the fence, the mulch, the grass and the flowers (without capturing the elusive flying Dogface), when I finally got a decent shot. Hooray! It’s blurry but distinguishable.
This butterfly stayed near the garden for the half-hour I was there. After feeding, the clever creature rested on the crepe myrtle leaves, only resting on the yellow leaves, never the green leaves. Camouflage?
It fluttered around other yellow butterflies its size that visited the garden, but I don’t know if it was guarding or courting. Once, three butterflies were circling each other. The other two flew off after feeding briefly.
I have photos of one of the other butterflies if you are interested. It may be a female Southern Dogface, but I’m not sure. I’m pretty sure it’s a Sulphur in any case.
Thank you for all of your help!
Thank you!
Signature: Ellen

Hi Ellen,
We got a bit of a chuckle at your attempt to photograph this Southern Dogface Butterfly, Zerene cesonia.  We went through a similar attempt to capture a good photograph of a Western Tiger Swallowtail in our our garden several years ago.  One of the beauties of digital photography over traditional analog photography is that it is much easier to keep shooting and shooting until you get a decent image.  As educators, we still believe that a firm foundation in analog photography makes better photographers despite the fact that they will not be working in analog professionally.  We are very pressed for time due to work obligations, and though you sent several submissions our way, we might not get them all posted this morning.

Letter 7 – Sulpher Chrysalis

Do you recognize this chrysalis?
Charlene

Charlene,
The orneriness in us wants to just reply “yes” and leave it at that, but we do not have a representative image on the site and are happy to have your Sulphur Butterfly Chrysalis. Since you did not provide us with a location and since your image is cropped oddly, we are not sure of the species. If you are in the American Southwest, it is probably a Senna Sulphur, Phoebis sennae, that feeds on cassia.

Great new image & a friend
Yes, sorry. My husband noticed I had supplied NO info. I’ll try and take a better picture. I am in Houston. And I do have a cassia in the backyard. Glad to know it is doing it’s job. I considered taking the plant out because it is quite ugly. I tried to trim it and did a very poor job. I’ll keep it around now. Thanks for the info. It was a rather ugly looking . How do such things turn into beauties??? By the way, I loved your sight and will be sure to pass it on to my friends!! This is really cool! I went outside to take a better picture of the chrysalis that I sent yesterday and some information on it and look what I found!! How strange that they crawled to the same place to “hang out” together!!!! Their host plant is across the yard. I live in Houston and would love an identification of these beauties. Thank you,
Charlene

Hi again Charlene,
We are certain you have a Senna Sulphur caterpillar and chrysalis. Wait for the gorgeous clear yellow butterflies to emerge and send a photo of them as well. They are strong fliers and difficult to approach.

Letter 8 – Sulphur Butterfly

butterfly
Hello again Bugman,
I like this subject better than the roach picture I just sent. What kind of pretty butterfly is this? We live in NC.
Nancy

Hi Nancy,
This is one of the Sulphur Butterflies in the genus Colias. It appears as though yellow spots in the black wing border are visible through the wings, indicating she is female, and the slight orange color indicated most probably the Alfalfa Butterfly, Colias eurytheme.