The Western Tiger Swallowtail has all the hallmarks of its genus and comfortably resides between the Pacific Ocean and the Rocky Mountains.
Like all Tiger Swallowtails, the Western Tiger Swallowtail is yellow with long, black stripes on its forewings, resembling that familiar pattern seen on tigers. The stripes closest to the body are darker and thicker than its Eastern and Canadian counterparts. Each hindwing has only one tail extension, unlike its relative, the Two-Tailed Tiger Swallowtail. These delicate tails may break or wear off over time. An orange eyespot in a field of blue sits at the bottom of the hindwings and is visible when the wings are open flat. A thick black band runs closely along the bottom of the forewings.
This species of Swallowtail is widespread in its region, living in various habitats from coastal areas to mountainous elevation. Up to 4 broods can be produced each year, securing its presence. The fleshy green caterpillar has a yellow and black collar by its head on a bulging, wide part of its body. Blue dots form a ring above this collar and also circle segments on the body. Two elongated eyespots are near the head. Each consists of a smaller, inner yellow spot usually connected by a blue block to a larger outer eyespot with black and blue pupils. Larvae feed on leaves of cottonwood, birch, ash, alder, aspen, willow, and other trees common to the region. Adults drink nectar and can be found flying all summer long. In warmer coastal areas, they may be seen most of the year. Because host trees grow in many habitats, Western Tiger Swallowtails can be seen as frequently in backyards as they are on remote hiking trails.
Scientific Name: Papilio rutulus
Butterfly or Moth
Size (Adult; Length): 90mm to 110mm (3.51in to 4.29in)
Note: An insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above as they are driven by environmental factors (such as climate change), available food supplies and mating patterns. Grayed-out selections indicate that the subject in question has not been reported in that particular territory. U.S. states and Canadian provinces / territories are clickable to their respective bug listings.
Butterfly and Moth Anatomy
Antennae: Butterflies and Moths have a pair of antennae on the head used as sensors.
Head: The head is home to the insect's eyes, antennae, and proboscis.
Thorax: Home to the three pairs of legs as well as vital internal organs.
Abdomen: Contains vital internal organs such as the heart(s) and reproduction facilities.
Forewing: The upper, forward wing pair used for flying.
Hindwing: The lower, rearward wing pair used for flying.
NOTE: Butterflies and Moths are part of the Lepidopteran order as they share many similarities.