The Red-spotted Purple butterfly is a beautiful, iridescent creature that relies on specific host plants during its larval stage. These plants play a crucial role in the lifecycle of the butterfly, as their leaves serve as the primary food source for the caterpillars. By understanding and cultivating these host plants in gardens or natural habitats, we can help support the population of Red-spotted Purples and contribute to the overall health of our ecosystems.
Some common host plants for Red-spotted Purple larvae include cherries (Prunus spp.), willows (Salix spp.), aspens (Populus spp.), serviceberries (Amelanchier spp.), birches (Betula spp.), and hawthorns (Crataegus spp.) source. These plants not only provide the necessary nutrients for the caterpillar’s growth and development, but also help to create a thriving environment for the adult butterflies to live and reproduce.
Red Spotted Purple Butterfly Overview
The Red-spotted Purple butterfly (Limenitis arthemis) is a beautiful and unique species of butterfly. It belongs to the Nymphalidae family, which includes Brush-footed butterflies. This species has two subspecies: L. a. astyanax and L. a. arthemis.
- Size & Wingspan: Red-spotted Purple butterflies have a wingspan that ranges between 2¼ and 4 inches (5.7 – 10.1 cm), making them moderate-sized butterflies.
- Flight Pattern: They are known for their distinctive flying style, which involves a series of rapid, zig-zag movements.
- Distribution: The species is commonly found throughout North America, with L. a. astyanax being a more widespread subspecies.
Some key differences between the two subspecies:
|Feature||L. a. astyanax||L. a. arthemis|
|Upperside Color||Blue to blue-green with iridescence||Dark with white bands|
|Underside Markings||Dark brown with red-orange bars and spots||Similar, but with an additional white band|
Both subspecies of the Red-spotted Purple butterfly are known to be visually appealing, and they are an excellent subject for photography or even just general admiration. The unique flying patterns and beautiful coloration of these butterflies make them a popular sight in gardens and natural habitats across North America.
Life Cycle and Development
Red-spotted purple butterflies lay their eggs on the leaves of their host plants, which include several species of trees like willow, cherry, and poplar1. Female butterflies tend to lay eggs individually on the underside of leaves. Some features of red-spotted purple eggs include:
- Shape: Round and flat
- Color: Greenish-white
The caterpillar phase is crucial for growth and development. Upon hatching, caterpillars consume the eggshell and then feed on the host plant leaves, eventually growing larger through several instars1. Some characteristics of red-spotted purple caterpillars include:
- Color: Green or brown with white speckles
- Two horn-like projections on the head
- Camouflaged appearance, resembling bird droppings
When the caterpillar has reached its final size, it pupates1. The pupa stage involves:
- Formation of a chrysalis
- Attaching to a twig or branch with a small silk thread
During this stage, the caterpillar undergoes a dramatic transformation, leading to the emergence of the adult butterfly. Pupa characteristics:
- Color: Green or brown, blending into surroundings
- Time spent: About 2 weeks
- Wingspan: 2¼ – 4 inches3
- Upperside: Blue to blue-green with iridescence
- Underside: Dark brown with red-orange spots and bars3
Table: Comparison of Red-spotted Purple Life Stages
|Life Stage||Color||Duration||Unique Features||Food Source|
|Eggs||Greenish-white||Days||Laid on host plant leaves||N/A|
|Caterpillars||Green/brown||Several weeks||Camouflaged, resembling bird droppings||Host plant leaves1|
|Pupa||Green/brown||About 2 weeks||Chrysalis||N/A|
|Adult||Blue-green||Adult life||Iridescent wings||Flowering plant nectar2|
Host Plants and Habitat
Host Plant Selection
Red-spotted purple butterfly larvae feed on various host plants, including:
- Wild cherries
Of these, the black cherry (Prunus serotina) and deerberry (Vaccineum stamineum) are preferred in Florida. These host plants belong to the deciduous tree family, Rosaceae.
The red-spotted purple butterfly prefers habitats that include:
- Forest edges
- Open woods
These butterflies thrive in areas with rich loam and clay soil. They can be seen enjoying the wild cherries and chokecherries found in their preferred habitat.
Feeding and Nectar Sources
The caterpillar of the Red Spotted Purple butterfly depends on specific host plants for sustenance. Some examples of their preferred plants include:
- Wild cherry (Prunus species)
- Birch (Betula species)
- Willow (Salix species)
- Poplar (Populus species)
Caterpillars consume leaves of these host plants to grow and develop into the adult butterfly stage.
Unlike caterpillars, adult Red Spotted Purple butterflies feed on a variety of nectar-rich flowers, rotting fruit, dung, carrion, and sap. They gather nutrients and energy from these sources, essential for their survival and reproduction. Some common nectar sources for these butterflies are:
- Milkweed (Asclepias species)
- Joe-pye weed (Eutrochium species)
- Purple coneflower (Echinacea species)
Here’s a comparison of the caterpillar and adult butterfly diets:
|Foods||Leaves of specific host plants||Flower nectar, rotting fruit, dung, carrion, sap|
By incorporating a mix of both host plants and nectar sources in a pollinator garden, more butterflies can be attracted, and better support the Red Spotted Purple butterfly’s life cycle.
Mimicry and Relationship with Other Butterflies
Mimicry in Red Spotted Purple
The Red Spotted Purple butterfly exhibits mimicry as an evolutionary strategy to deter predators. This butterfly’s unique patterns and colors resemble those of toxic or unpalatable species, causing potential predators to avoid them.
- Examples of mimicry in Red Spotted Purple:
- Coloring resembles that of the toxic Pipevine Swallowtail
- Wing patterns imitate the unpalatable White Admiral
Red Spotted Purple and White Admiral
The Red Spotted Purple is closely related to the White Admiral butterfly. These two butterflies occasionally interbreed, resulting in hybrid offspring showing characteristics of both parent species.
- Relationship between Red Spotted Purple and White Admiral:
- They have similar wing patterns
- Occasional hybridization can occur
Comparison Table: Red Spotted Purple and White Admiral
|Feature||Red Spotted Purple||White Admiral|
|Wing pattern||Red spots and blue hue||White band and blue hue|
|Hybridization potential||Possible with White Admiral||Possible with Red Spotted Purple|
Red Spotted Purple and Pipevine Swallowtail
The Red Spotted Purple butterfly’s mimicry extends to its resemblance of the Pipevine Swallowtail, a toxic species which deters predators.
- Characteristics found in both species:
- Red spots on the wings
- Dark coloration
- Similarities in wing patterns
By imitating the toxic Pipevine Swallowtail, the Red Spotted Purple gains an advantage in predator evasion, thus increasing its chances of survival. This is a prime example of how mimicry plays a vital role in the evolution and success of various butterfly species.
Geographical Distribution and Regional Varieties
Eastern United States
- Prefers deciduous forests and woodland edges
- Blackish-blue color with red spots on its wings
In the Southwest, the Limenitis arthemis arthemis, or white admiral, is found. It shares similar features with the red-spotted purple butterfly.
|Red-Spotted Purple||White Admiral|
|Regions||Eastern United States||Southwest|
|Color||Blackish-blue with red spots||Blackish-blue with white band|
In Florida, the red-spotted purple butterfly can also be observed, with local variations in appearance.
- Brighter coloration
- Tends to favor warmer climates
Overall, different regional varieties of red-spotted purple butterflies can be found throughout the Eastern US, Southwest, and Florida, each with distinct features and habitat preferences.
Cultivating Host Trees for Red Spotted Purple Butterflies
Red spotted purple butterflies primarily lay their eggs on the leaves of cottonwood and wild cherry trees. When planting host trees, ensure they have enough space to grow, as both cottonwood and wild cherry trees can become quite large. For example, cottonwoods can become large, while wild cherries typically remain a small tree.
Cottonwoods and wild cherries require different levels of care.
Cottonwoods: These trees are relatively low-maintenance and can tolerate wet soil conditions. However, they can be susceptible to diseases such as cankers and cottonwood leaf beetles.
Wild Cherries: They require more care as they are prone to diseases like fire blight and powdery mildew. Regular pruning can help manage these issues, along with monitoring for pests like tent caterpillars.
To help your host trees thrive and attract red spotted purple butterflies, consider the following conditions for each tree type:
- Full sun or partial shade
- Moist to wet soils
- Adaptable to various soil types
- Full sun
- Well-drained soils
- Adaptable to various soil types
|Tree Type||Sun Requirements||Soil Requirements||Maintenance||Diseases|
|Cottonwoods||Full/Partial||Moist/Wet||Low||Cankers, Leaf Beetle|
|Wild Cherries||Full Sun||Well-drained||Moderate/High||Fire Blight, Mildew|
Creating the right environment for your host trees will not only help them grow but will also provide the needed resources for red spotted purple butterflies and other pollinators. With proper care and attention, your garden will become a haven for butterflies and a beautiful, lush specimen in any landscape.
Conservation and Viewing Tips
- Plant native host plants for caterpillars
- Reduce pesticide use to protect butterfly populations
- Preserve habitats to support natural life cycles
Red spotted purple butterflies play an essential role in ecosystems, and it’s crucial to support their conservation. One way to do this is by planting native host plants, such as Prunus species like wild cherry, plum, and chokecherry trees, as the caterpillars depend on these for food (source).
Another important aspect is reducing pesticide use to prevent harm to butterfly populations. Preserving habitats that support the natural life cycle of these butterflies is also necessary.
Tips for Observing Red Spotted Purple Butterflies
1. Look for moist habitats
These butterflies are commonly found in moist habitats, such as wetlands and forest edges (source).
2. Observe from a distance
For a clear dorsal view, keep a safe distance and use binoculars to observe them while perched.
3. Watch male butterflies
Male butterflies are more active and are known to perch on trees, making them relatively easier to observe.
Following these tips will enhance your butterfly-watching experience and contribute to the conservation of the red spotted purple butterfly. Happy viewing!
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 – Red-Spotted Purple Catepillar
I found your website while searching for a caterpillar ID, and just spent 2 hours enjoying all your wonderful photos and comments! I found this bird-dropping mimic on a weed in my garden which *might* be a wild cherry since I have a large one in my yard. I am not sure though because the plant is only 10 inches tall! Sadly the next day the caterpillar was gone. I live in Northern Virginia. I think it is a red-spotted purple, what do you think? Thanks for looking at my critter and for having such an awesome site!
The Red-Spotted Purple, Limenitis arthemis astyanax, and the White Admiral, Limenitis arthemis arthemis, are subspecies with different ranges that overlap. According to BugGuide: “White Admiral ( Limentis arthemis form arthemis ) – the northern form, basically black and white in the east, In the west specimens tend to have red spots on the hind wing and are called Western White Admirals ( Limentis arthemis form rubrofasciata ). In the SE USA and as far north as extreme southern Ontario this species is black and purple (no white band)and is called Red-Spotted Purple ( Limentis arthemis form astyanax ). As there 3 forms are regarded as being the same species, intergrades between them are quite common.” Since you have graciously provided us with a location, we can presume you do have the southern Red-Spotted Purple. Thank you for sending in a new caterpillar for our site.
Letter 2 – Viceroy Caterpillar, not Red Spotted Purple Caterpillar
Mystery Caterpillar on Curly/Corkscrew Willow
June 23, 2010
There are quite a few of these on a curly willow in my yard in Central Arkansas, USA. Just noticed them today (June 23). They’re munching out on the willow… there are some others that are a darker brown color, but otherwise look the same. Any ideas?
Amy The Bug Girl
Little Rock, AR, USA
This is a Red Spotted Purple Caterpillar, Limenitis arthemis. BugGuide has a fine example that documents the metamorphosis of the caterpillar to an adult.
Yay! I am so excited!
I usually get monarchs on my butterfly weed, so I’m excited to have a new visitor on the willow this year!
What’s funny is, the willow was in a flower arrangment that I got in the early spring – just the bare, curly twigs. It started to root & leaf out, and I hated to throw it out, so I just stuck it down in some planters outside & it’s been very happy there! I’m glad it’s proven to be a host plant for such a beautiful butterfly.
Thanks for your quick reply!
Imposter! Actually, it was a Viceroy!
July 3, 2010
I sent you a question that you kindly answered back on June 24, about a mystery caterpillar on the curly willow in our yard. We’d determined it was a Red Spotted Purple (and it did look just like that caterpillar). Well, imagine my surprise when I went out into the garden early this morning to find a dozen+ VICEROY butterflies! I am attaching some photos for you 🙂
Amy The Bug Girl
Little Rock, AR, USA
First, we apologize for our misidentification of your Viceroy Caterpillar last month. In our defense, the Viceroy, Limenitis archippus, and the Red Spotted Purple, Limenitis arthemis astyanax, are in the same genus and their caterpillars look very similar. We especially like that your one photo shows the Chrysalis below the newly emerged adult butterfly. It is also wonderful that you provided us with views of both the open and closed wings.
- Helpful Comment
Viceroy vs Red-spotted Purple caterpillars
July 3, 2010
Photos partly down this page shows the difference between the two caterpillars. http://www.butterflyfunfacts.com/butterflysimilarities.php
Viceroy caterpillars have more spikes on their humps on their backs. Red Spotted-purple caterpillar have very minimal humps on their backs.
Love your site!
Letter 3 – Red Spotted Purple Caterpillar
Location: Florida Panhandle
July 19, 2017 7:29 am
Would love to know what this little guy is. Caught him eating my apple tree so i remove him and took him someplace else away from my trer
Signature: -Curious Tree Owner
Dear Curious Tree Owner,
Based on this BugGuide image, we are confident that this is the caterpillar of a Red Spotted Purple, arguably one of the most beautiful North American butterflies. A single caterpillar is not going to do any serious damage to your apple tree by feeding on leaves, and caterpillars removed from their host plant generally have little chance for survival. We hope in the future, should you encounter another Red Spotted Purple Caterpillar feeding on your apple tree leaves, you will show a little more tolerance and allow it to remain. In the event you still feel compelled to remove solitary Red Spotted Purple Caterpillars from your apple tree, BugGuide does provide this list of potential host plants: “A variety of deciduous trees: willows and poplars (Willow family), cherries, apples and pears (Rose family), birches (Birch family), oaks and beeches (Beech family), Basswood (Linden family) and others. Also recorded from currant and blueberry bushes.”
You’ll be happy to know I found the little guy and placed it back on the tree. 🙂
Wow, we are happy we caught your request early. For your kindness, we are tagging your submission with the Bug Humanitarian Award.
Letter 4 – Red Spotted Purple Caterpillar
Subject: Red Spotted Purple Caterpillar
Location: High Springs, Fl.
August 15, 2017 3:10 pm
Just wanted to share these photos of a Red Spotted Purple caterpillar that was on my wild cherry tree. My husband got me the tree so that I could have the butterflies but we get very few of them. Their survival rate is low on our property due to so many predators. For protection the next ones to show up are going into the habitat with cuttings . They do become gorgeous butterflies.
Thanks so much for sending in your images of a Red Spotted Purple Caterpillar. We agree that the Red Spotted Purple is a gorgeous butterfly, and sometime back we waxed philosophically that it might be the prettiest North American butterfly.
Letter 5 – Red Spotted Purple Caterpillar becomes Pupa
Red Spotted Purple update (caterpillar, pre-pupa, pupa)
For a few days ago my Red Spotted Purple caterpillars had the honour to be on your website. Today I am sending some more pictures of the later development: the last instar caterpillar, the pre-pupa, and the pupa. Best regards, and keep making people happy with your website,
Thanks for the update and awesome photos. Actually, your previous photos are still on our site, but in the interest of new additions, they needed to be removed from the homepage. Their permanent home, for as long as we have a site, is on the fifth caterpillar page.
Letter 6 – Red Spotted Purple Caterpillars
Young caterpillars and hibernaculum – Redspotted Purple
Your site is really fantastic and I would like to make a contribution to your picture collection. So, what I have for you is a hibernaculum, a small caterpillar and a medium sized caterpillar of the Redspotted Purple (Limenitis arthemis astyanax). I found them on a bush of Wild Cerry on the 2:nd of May (yesterday)in Madison/Wisconsin close to Lake Mendota, all on the same twig. They are standing on my kitchen table now and I am planning to provide you with more pictures of their development. Last year I was breeding about 10 caterpillars from the same region, and all of them were Redspotted Purples, no White Admirals or mixed forms were between them. Thank you so much for providing such a wonderful site!
Thomas Werner, PhD
Laboratory of Molecular Biology
University of Wisconsin-Madison
We are posting your two caterpillar images, but we are having trouble making out the Hibernaculum in the third photo, unless you are speaking about the plant bud.
I am very happy to see my pictures on your side. So, the hibernaculum is the dried little leaf. The caterpillars cut off the distal part of the leaf in autumn, leaving the central part intact and cover it with silk, so that it forms a tube. The hibernaculum is fastened to the twig with silk and doesn’t fall off during winter. I hope I could help you finding it on the picture. My medium sized caterpillar has just molted, so here comes an addition to the collection.
Hi again Thomas,
Thanks for the clarification and the addition. You are such a proud father.
Letter 7 – Red Spotted Purple Chrysalis
Geographic location of the bug: Hampton, VA
Time: 05:22 PM EDT
Found this guy on my front porch. I’ve seen similar shaped ones but not same color.
How you want your letter signed: Elissa S.
Letter 8 – Red Spotted Purple Pupa and Butterfly: The Saga Continues!!
Red Spotted Purple – A Happy End
The photo model hatched today, which provided us with a nice photo series: The Red Spotted Purple (Limenitis arthemis astyanax). To end this story, I am sending a picture of the pharate pupa and the hatched butterfly (sitting next to its exuvie). I will give you a little break from my letters now, but I will return, because I am preparing a photo series of two very interesting and closely related species: Asterocampa celtis (Hackberry Emperor) and A. clyton (Tawny Emperor). I have already some gorgeous pictures of very small and bigger caterpillars of both species, but I will wait until I have photos of the pupae as well.
Thank you for keeping us abreast of this fascinating saga. We eagerly await your next series. Have a wonderful day.
Daniel and Lisa Anne
Letter 9 – Very Tattered Red Spotted Purple in Campbell, Ohio
Subject: Red Spotted Purple
Geographic location of the bug: Campbell, Ohio
Time: 11:03 AM EDT
Daniel has frequently stated that the Red Spotted Purple is one of the most beautiful North American butterflies, though this tattered individual will most likely not elicit many votes from anyone who has never seen a perfect example of this lovely butterfly. Though the image isn’t much to look at, Daniel wanted the documentation, and then the next day when he had no camera, he was lucky enough to observe an individual with more intense color and lacking wing damage because it had not been traumatized so much during its short life.
Letter 10 – What Decapitated the Red Spotted Purple???
Subject: Can you identify this butterfly?
Location: North Alabama
August 29, 2013 10:11 pm
My seven-year-old daughter found this butterfly near our North Alabama home in early August. We’ve tried to identify it without success. We wish we had a picture of the wings folded, but the picture of open wings shows a lot of detail. Thanks for your help!
Signature: Curious Mom & Daughter
Dear Curious Mom & Daughter,
This beautiful butterfly is a Red Spotted Purple, and that is a very easy identification for our staff, but we are really curious about its missing head. What decapitated the Red Spotted Purple and why? is what we are wondering. When we identify decapitated Longicorn heads, we can hypothesize that some predator ate the nutritious body and left the head, but we can’t come up with a reason why a predator would eat only the head of the butterfly and leave the rest of the body. Perhaps one of our readers can help solve this mystery.