enchrysa

G. enchrysa Davis and Pellmyr

Adult Characteristics

Wing expanse 15.5-20 mm. Forewings in most areas uniformly pale ochreous, often with a golden luster; rarely pale straw-colored. In the eastern portion of the range, some populations with ochreous to dark ochreous color, a light subtornal patch and sometimes a slight costal patch near the apex. Hindwings darker, gray.

Comparison with similar species

This yellow, uniformly colored species should be unmistakable. It often coexists with the yellow but spotted G. piperella and the uniformly colored, darker brownish G. politella.

Hosts, oviposition, and larval feeding habits

Heuchera cylindrica and H. grossulariifolia (Saxifragaceae). Females oviposit into the floral ovary of the host, and several larvae per capsule complete the first one or two larval instars feeding on seeds. Subsequent biology is unknown.

Greya enchrysa ovipositing into the ovary of a H.cylindrica flower.

Geographic Distribution

In the drier interior regions of southern British Columbia and Alberta, Canada, and in interior Washington and Oregon, Idaho and western Montana, USA.

Habitat

In open, grassy pine forest or near rockfaces in open country where the host is found growing in crevices and ledges. Elevational range 250-1500 m. It often coexists with G. piperella and G. politella.

Characteristic habitat in Nez Perce Co., Idaho; Heuchera grows along lower edge of talus.

Ecological notes

Greya enchrysa is an efficient passive pollinator during oviposition, transporting ample pollen of its host on the abdomen between flowers. Larvae consume relatively few seeds, and the species could thus be a mutualist relative to the host. An abundance of other pollinators, particularly bumblebees, mask the beneficial effects of the moth on seed production in studied populations (Pellmyr et al. 1996).

Further ecological aspects of G. enchrysa and the species that it interacts with are currently under study by John Thompson and David Althoff at Washington State University.

References

Davis, D.R., O. Pellmyr & J.N. Thompson. 1992. Biology and systematics 
          of Greya Busck and Tetragma n. gen. (Lepidoptera: Prodoxidae). 
          Smiths. Contrib. Zool. 524:1-88.
Pellmyr, O., J.N. Thompson, J. Brown & R.G. Harrison. 1996. Evolution 
          of pollination and mutualism in the yucca moth lineage. 
          Amer. Nat. 148:827-847.

Holotype in USNM.

About this page

Olle Pellmyr
E-mail: pellmyr@ctrvax.vanderbilt.edu.
Dept of Biology, Vanderbilt University, Box 1812-B Nashville, TN 37235, USA

Title Illustrations: Male from Asotin Co., Washington, and female from Wallowa Co., Oregon.