Hemileuca nuttalli

Strecker, 1875

Nuttall's Sheep Moth, Nuttall's Buck Moth

Hemileuca nuttalli, or Nuttall's sheep moth, is a medium-sized saturniid native to western North America. It is one of approximately 24 in the Hemileuca, commonly known as buck moths or sheep moths. The species exhibits distinctive yellow-orange and black wing patterning and has urticating larvae that feed on woody shrubs. are and do not feed. In behavioral studies, male H. nuttalli showed no attraction to Argiope aurantia spider lures, unlike some closely related species, suggesting potential -prey coevolutionary dynamics.

Hemileuca nuttalli 20363087 by Don Loarie. Used under a CC BY 4.0 license.

Nuttall's sheep moth, Craters of the Moon National Monument (36236116024) by Craters of the Moon National Monument & Preserve. Used under a Public domain license.

Nuttall's Sheepmoth - Hemileuca nuttalli by Jacob W. Frank. Used under a Public domain license.

Pronunciation

How to pronounce Hemileuca nuttalli: /hɛmɪˈluːkə nʌˈtælaɪ/

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

Identification

Distinguished from other Hemileuca by the combination of yellow-orange hindwings with a thick curved black stripe, forewings with yellow-to-white gradient, and specific eyespot pattern (black with white center on forewings, small black eyespot on hindwings). The 60–65 mm wingspan is relatively small for the . Males of H. nuttalli can be distinguished from H. hera and H. magnifica by their lack of attraction to Argiope aurantia spider lures in behavioral assays.

Images

Habitat

Grassland and shrub-dominated . typically fly well above vegetation . Associated with plants including Purshia tridentata (bitterbrush), Symphoricarpos (snowberries), and Ribes species (currants/gooseberries).

Distribution

Western North America: south-eastern British Columbia, eastern Washington, eastern Oregon, north-eastern California, Idaho, Nevada, northern Arizona, Utah, Montana, Wyoming, Colorado, and north-western New Mexico.

Diet

Larvae feed on Purshia tridentata, Symphoricarpos , and Ribes species. lack functional mouthparts and do not feed.

Host Associations

Purshia tridentata - larval bitterbrush
Symphoricarpos - larval snowberry
Ribes - larval currant and gooseberry

Life Cycle

Females lay in rings around small twigs of plants. Larvae are black with yellow urticating spines. are short-lived and do not feed.

Behavior

activity. Males engage in circular locating flights (500 m to 1 km diameter) when searching for females, then follow gradients (~100 m) to locate calling females. When a pheromone plume is detected, flight paths become smaller in diameter to map geospatial pheromone concentrations. Males showed no attraction to Argiope aurantia spider pheromone lures in experimental studies, unlike H. hera and H. magnifica.

Hemileuca heraSimilar size and coloration; males strongly attracted to Argiope aurantia lures, unlike H. nuttalli
Hemileuca magnificaClosely related in same clade; males strongly attracted to Argiope aurantia lures, unlike H. nuttalli
Hemileuca eglanterinaAnother sheep moth with variable coloration; differs in geographic range and lure response patterns

More Details

Taxonomic history

Originally described as Pseudohazis nuttalli by Ferdinand Heinrich Hermann Strecker in 1875.

Phylogenetic context

Molecular phylogenetic studies place H. nuttalli in a clade with H. hera and H. magnifica, yet it exhibits a distinct behavioral phenotype regarding lure response.