Home / Hawk Moths (Sphingidae) / Big Poplar Sphinx Moth(Pachysphinx occidentalis)

Big Poplar Sphinx Moth(Pachysphinx occidentalis)

The big poplar sphinx moth is a member of the family of hawk moths. They are found throughout North America and can be found in two color morphs – a pale one and a dark one. These moths have two subspecies namely Pachysphinx occidentalis occidentalis and Pachysphinx occidentalis regalis.

Big Poplar Sphinx Moth


Scientific Classification

  • Family: Sphingidae
  • Genus: Pachysphinx
  • Scientific Name: Pachysphinx occidentalis

Description and Identification


The larvae are green with yellow stripes.

Big Poplar Sphinx Moth Caterpillar



After the larva goes through all of its instars, they get ready to pupate underground in shallow burrows.

Adult Moth

Sexual Dimorphism: Present but not prominent.

Color and Appearance

Forewing: When the wings are opened, they are yellow-brown when the moth is pale and dark gray when it is dark in color. When the wings are closed, the well-defined lines and bands remain observable.

Hindwing: When the wings are opened, a crimson patch covering a significant part of the upper side is visible. When the wings are closed, the pink patch is no more visible, yet the lined patterns can be seen.

Average wingspan: 13-15 cm

Flight pattern: Erratic

Season: May to September

Pachysphinx occidentalis



The eggs are laid on the host plant’s leaves.

Big Poplar Sphinx Moth Eggs


Quick Facts

DistributionCanada and the US, including North Dakota west to eastern Washington; south to Texas, southern California, and Baja California Norte.
HabitatRiparian areas and suburbs
Lifespan of AdultsNot recorded
Host PlantsCottonwood, poplar, and Salix
Adult DietFlower nectar

Did You Know

  • English entomologist Henry Edwards first described this species in 1875.
Big Poplar Sphinx Moth Picture


Leave a comment

Your email address will not be published. Required fields are marked *