We continue our series on Jamaica’s endangered species this week with a look at the Giant Swallowtail butterfly. Have questions, comments? Email williamsp@jamaicaobserver.com.

THE giant swallowtail butterfly, known scientifically as Papilio homerus, is Jamaica’s largest butterfly.

It is also the largest butterfly in the Americas, with its wingspan averaging some six inches.

Adults of the species have black wings with yellow markings near the margins, while spots form a diagonal band across the fore wings.

Caterpillars, on the other hand, are dark brown with creamy white mottled markings. When caterpillars are disturbed, they display horn-like orange glands, called osmeteria, which emit an unpleasant odour.

Life cycle

Like other butterflies, the Giant Swallowtail passes through varies stages in its life cycle – egg, larva (caterpillar), pupa (chrysalis) and adult. The adult is what is known as the butterfly.

Adult females lay yellow-green eggs singly on host plants. Caterpillars hatch and develop through several stages before forming a chrysalis or pupa, which is attached to the host plant by the back end and held in an upright position by a silk thread around the middle.

Home

Here in Jamaica, the Papilio homerus may be found inside the Cockpit country, as well as in the Blue and John Crow mountains.

Feeding habits

They feed on leaves of host plants, among them citrus, gas plant and prickly ash and rue. Their favourite flowers are honeysuckle, azalea, goldenrod and orange trees. In fact, so great is the Giant Swallowtail’s love of orange trees that in some circles, they are referred to as “orange dogs”.

Survival threats

Threats to the species – which is among the more than 22 endangered animals and plants listed under Jamaica’s Wildlife and Protection Act – include parasitic wasps in the egg and bacteria in the larval stages. Forrest clearing is also a threat since it puts the eggs at risk.

Sources: insects.tamu.edu/fieldguide/cimg270.html; www.ivyhall.district96.k12.il.us/4TH/KKHP/1INSECTS/swalotlfax.html; www.jsdnp.org.jm/papilioho.htm