Anise Swallowtail Caterpillar vs Black Swallowtail Caterpillar: A Fascinating Comparison

Anise swallowtail caterpillar and black swallowtail caterpillar are two fascinating butterfly larvae known for their striking appearance and unique feeding habits.

Both species belong to the Papilionidae family, but they exhibit some differences in color patterns and host plants that set them apart.

This article aims to provide an insightful comparison between the two, shedding light on their key characteristics and ecological roles.

Anise Swallowtail vs Black Swallowtail Caterpillars

Distinguishing Physical Features

Anise Swallowtail caterpillars are part of the Papilio zelicaon species, featuring large larvae that appear pale green with black bands containing orange spots.

The amount of green and black on the larvae may vary based on environmental conditions, such as humidity and temperature.

Black Swallowtail caterpillars belong to the Papilio polyxenes species and have a more distinctive appearance compared to Anise Swallowtail caterpillars.

The adult Black Swallowtail butterfly exhibits black upper wings with two rows of yellow spots.

You will also notice blue, and orange-red coloring on the wings, with females showcasing smaller spots and a more iridescent-blue tone.

Here are the main differences in physical features:

• Anise Swallowtail: Pale green with black bands containing orange spots ¹
• Black Swallowtail: Black wings with yellow, blue, and orange-red coloring, and iridescent-blue for females

Comparison of Size

Regarding size, female Black Swallowtail butterflies tend to be larger than males, with a wingspan of 3¼ to 4¼ inches. The Anise Swallowtail has a wingspan of 2.4 to 4 inches.

A comparative table showing the size differences:

Habitat and Distribution

Anise Swallowtail Caterpillar

The Anise Swallowtail caterpillar can be found throughout Western North America, including the California coast and Utah. Their habitats may vary, but they are generally found in:

• Open fields
• Bare hills
• Gardens

These caterpillars usually feed on host plants such as anise, dill, fennel, and parsley.

Black Swallowtail Caterpillar

The Black Swallowtail caterpillar has a wide distribution across southern Canada, the eastern and mid-western United States to the Rocky Mountains, and southwest into Arizona and northern Mexico. Their preferred habitats include:

• Open areas
• Fields
• Meadows
• Parks
• Wetlands
• Prairies

Black Swallowtail caterpillars typically feed on plants such as parsley, dill, and carrot leaves.

Comparison Table

Host Plants and Feeding Behavior

Anise Swallowtail Caterpillar

The Anise Swallowtail caterpillar belongs to the Papilionidae family. It feeds primarily on plants from the carrot and citrus families (Apiaceae and Rutaceae). Examples of preferred host plants:

• Fennel (Foeniculum vulgare)
• Lomatium dissectum
• Parsley

These larvae change their appearance as they grow. Small larvae resemble bird droppings, while larger ones have pale green and black bands with orange spots.

Black Swallowtail Caterpillar

The Black Swallowtail caterpillar also belongs to the Papilionidae family. It feeds mainly on plants within the Apiaceae family, such as:

• Parsley
• Dill
• Carrot

These caterpillars go through similar appearance changes, starting as bird-dropping mimics before displaying green and black bands with yellow spots as they grow.

Comparison Table:

In conclusion, both Anise and Black Swallowtail caterpillars feed on plants from the Apiaceae family, but Anise Swallowtails also feed on Rutaceae plants. They exhibit similar larval appearance changes but differ in color patterns.

Life Cycle and Development

Anise Swallowtail Caterpillar

The Anise Swallowtail Caterpillar (Papilio zelicaon) has a fascinating life cycle. The eggs are laid on host plants, such as sweet cicely or anise root, and the larvae resemble bird droppings when they are small.

As they grow into larger caterpillars, their appearance changes to a pale green color with black bands containing orange spots. Environmental factors, such as heat and humidity, can affect the coloration of these caterpillars.

The pupa stage, in which the caterpillar forms a chrysalis and transforms into the anise swallowtail butterfly, may result in brown or green pupae.

Pros:

• Well-camouflaged due to its resemblance to bird droppings
• Coloration changes according to environmental conditions

Cons:

• Color changes may make it difficult to identify

Black Swallowtail Caterpillar

The Black Swallowtail Caterpillar (Papilio polyxenes) also has an interesting life cycle, beginning with eggs laid on plants in the carrot family (Apiaceae).

These caterpillars are various shades of green, featuring narrow black bands on each body segment and interrupted by yellow-orange dots. As they grow, they reach lengths of up to 2 inches.

They have a defense mechanism called osmeteria, which are retractable, forked structures that release a foul odor when threatened. In the pupal stage, they spin a silk pad to attach themselves to a surface before forming a chrysalis.

Identifying Adult Butterflies

Anise Swallowtail Butterfly

The Anise Swallowtail butterfly is a member of the Papilionidae family. Males and females exhibit some degree of sexual dimorphism.

• Wingspan: Typically ranges from 2.4 to 4 inches
• Appearance: Yellow with black markings, blue and orange spots near the tail.
• Habitat: Found mainly in the western United States, preferring open meadows and hillsides.

Black Swallowtail Butterfly

The Black Swallowtail butterfly belongs to the same family as the Anise Swallowtail.

• Wingspan: Approximately 2.7 to 4.1 inches (7 to 10.5 cm).
• Appearance: Black with yellow markings on the edge, blue and red spots on the hindwings.
• Habitat: Primarily in the eastern United States, inhabiting gardens, fields, and meadows.

Here’s a comparison table highlighting the differences between the Anise Swallowtail and the Black Swallowtail butterflies:

Both butterflies can be confused with Tiger Swallowtail, Pipevine Swallowtail, and Spicebush Swallowtail due to their similar appearances. However, observing their distinct markings and color patterns can help differentiate them.

Raising and Caring for Caterpillars

Anise Swallowtail Caterpillar

Anise swallowtail caterpillars are typically found on plants in the carrot family, like anise and fennel. Female anise swallowtails lay their eggs on these host plants, providing a food source for the developing caterpillars.

To raise anise swallowtail caterpillars:

• Obtain a third instar caterpillar or a live female to lay eggs
• Provide potted parsley or fennel plant for food and shelter
• Create a safe environment using a cage or enclosure
• Mist the cage daily for humidity and ventilation

Remember to be gentle when handling caterpillars to avoid injury.

Black Swallowtail Caterpillar

Black swallowtail caterpillars also enjoy plants from the carrot family, such as parsley, dill, and fennel. They can be found munching on herbs in gardens and open areas.

To raise black swallowtail caterpillars:

• Obtain a third instar caterpillar or a live female to lay eggs
• Provide potted parsley or dill plant as their food source
• Set up a suitable enclosure or cage to keep them safe
• Ensure a humid environment by misting the cage daily

Handle them with care to prevent injuries.

Comparison Table

Conservation Status and Human Impact

Anise Swallowtail

The Anise Swallowtail (scientific classification: Papilio zelicaon) is native to western North America, where it coexists with other species like the Western Tiger Swallowtail (Papilio rutulus).

This butterfly thrives in various habitats including roadside, gardens, and open fields. However, the conservation status of Anise Swallowtail is not directly provided by NatureServe or other major conservation organizations.

Black Swallowtail

On the other hand, the Black Swallowtail (scientific classification: Papilio polyxenes) is native to eastern North America and shares some habitats with the Eastern Tiger Swallowtail (Papilio glaucus).

Its subspecies, the Indra Swallowtail (Papilio indra), is found in the western regions. The Black Swallowtail is often seen in gardens and wooded areas.

Similar to the Anise Swallowtail, its conservation status is not explicitly mentioned by NatureServe or other major conservation organizations.

Conclusion

Both Anise and Black Swallowtails are similar in size and frequently mistaken for each other due to their overlapping habitats. They coexist with different subspecies of tiger swallowtail butterflies.

As of now, neither species is facing significant threats or concerning conservation status, and they continue to thrive in their natural habitats, gardens, and roadsides.