Papilio zelicaon

Lucas, 1852

Anise Swallowtail

Species Guides

Papilio zelicaon nitra
Papilio zelicaon zelicaon(Anise Swallowtail)

Papilio zelicaon, the Anise Swallowtail, is a common of western North America. It is distinguished by yellow wings with black bands, blue spots near the hindwing tails, and a wingspan of 52–80 mm. The is smaller than the western tiger swallowtail and lacks the latter's converging black stripes. A darker , P. z. nitra, occurs rarely throughout the range.

Papilio zelicaon nitra by (c) Colin Croft, some rights reserved (CC BY), uploaded by Colin Croft. Used under a CC-BY license.

Papilio zelicaon by (c) Hydrocycler (Elizabeth Dougherty), some rights reserved (CC BY), uploaded by Hydrocycler (Elizabeth Dougherty). Used under a CC-BY license.

Papilio zelicaon by (c) P Holroyd, some rights reserved (CC BY), uploaded by P Holroyd. Used under a CC-BY license.

Pronunciation

How to pronounce Papilio zelicaon: //pəˈpɪlioʊ zɛlɪˈkaʊn//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Distinguished from the western tiger swallowtail (Papilio rutulus) by smaller size, shorter body, and absence of vertical black striping patterns that converge toward the tail. The yellowish-orange to red eyespots near the wing tails, each containing a black pupil, are distinctive features.

Images

Habitat

Occurs in fairly open country, most frequently on bare hills or mountains, in fields, or at roadsides. Often found in towns, gardens, and vacant lots.

Distribution

Western North America from British Columbia and North Dakota south to the Baja California Peninsula and other parts of Mexico. Occasionally reported from the southeastern United States, but normal range does not extend east of New Mexico. Distribution records include Alberta and Saskatchewan in Canada.

Seasonality

In northern parts of the range, the chrysalis hibernates. are active during warmer months; specific period varies by latitude and elevation.

Diet

feed on nectar from various plants. Caterpillars feed on members of the carrot (Apiaceae), including fennel, and some members of the citrus family (Rutaceae).

Host Associations

Foeniculum vulgare - larval Common garden fennel
Apiaceae - larval Members of the carrot
Rutaceae - larval Some members of the citrus

Life Cycle

females lay singly on undersides of plant leaves. Five larval instars precede . Caterpillar forms a chrysalis attached to host plant. In northern parts of range, chrysalis hibernates. Has been observed to exhibit non- in California under certain conditions.

Behavior

Caterpillars, when disturbed, suddenly evert bright orange osmeteria () from just behind the ; these glandular structures emit a foul odor. Early instar larvae resemble bird droppings, providing protective camouflage. Later instars have large eyespots that may startle .

Ecological Role

of various flowering plants. Larvae serve as food source for including birds, reptiles, and small mammals. Chemical from plants provides defense against predators.

Human Relevance

Used in scientific research on dynamics, plant suitability, and studies. Occasionally considered a minor pest in gardens where caterpillars feed on cultivated fennel or related plants. Subject of long-term monitoring studies in California since 1972.

Similar Taxa

Papilio rutulusOverlapping range in western North America; distinguished by larger size, longer body, and presence of converging black stripes toward the tail that P. zelicaon lacks.

More Details

Research significance

Papilio zelicaon has been extensively used in studies by researchers including Art Shapiro at UC Davis, who has conducted field experiments placing lab-generated cohorts on multiple plants throughout the ' range from sea level to subalpine zones. These studies have tested hypotheses about and host plant effects.

Diapause plasticity

Research by Shapiro (1984) documented non- in California , demonstrating adaptive plasticity in diapause induction. This Type III diapause-induction curve allows some individuals to develop without diapause under favorable autumn conditions.