Ethmia delliella
(Fernald, 1891)
Ladder-backed Ethmia Moth
Ethmia delliella, commonly known as the ladder-backed ethmia , is a small moth in the Ethmiidae (sometimes placed in Depressariidae). have a forewing length of 9–12 mm with distinctive black-and-white patterning that reflects metallic steel blue. The ranges from the Gulf region of Texas and Mexico southward through Central America to Rica. Adults are active from March to October in Texas and April to August elsewhere, with multiple per year.

Pronunciation
How to pronounce Ethmia delliella: //ˈɛθ.mi.ə dɛl.iˈɛ.lə//
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Identification
Distinguished from similar Ethmia by the specific pattern of black markings on white forewings with metallic steel blue reflections, combined with the brown-tinged hindwing apex. The upturned labial palps (resembling small horns between the ) help distinguish Depressariidae/Ethmiidae from superficially similar tortricid leafroller moths.
Images
Appearance
Small with forewing length of 9–12 mm. Forewings white with black markings that reflect metallic steel blue. Hindwings white, becoming slightly to strongly brown toward the apex.
Distribution
Gulf region of Texas and Mexico; west coastal plain of Mexico; Chiapas, Mexico; El Salvador; Rica.
Seasonality
March to October in Texas; April to August elsewhere in range. Multiple per year.
Diet
Larvae feed on Ehretia elliptica and Cordia alliodora.
Host Associations
- Ehretia elliptica - larval plant
- Cordia alliodora - larval plant
Life Cycle
Multiple per year.
Similar Taxa
- Ethmia discostrigellaSimilar with black-and-white patterning, but E. discostrigella larvae feed on Mountain Mahogany (Cercocarpus montanus) rather than Ehretia or Cordia
- Tortricidae (leafroller moths)Superficially similar resting posture and size, but distinguished by upturned labial palps in Ethmia
Sources and further reading
- BugGuide
- Wikipedia
- GBIF taxonomy match
- iNaturalist taxon
- NCBI Taxonomy
- Catalogue of Life
- What's in a Name? Leslie Saul-Gershenz and Norm Gershenz | Bug Squad
- Bug Eric: My Personal National Moth Week, 2017
- Bug Eric: September 2017
- Bug Eric: New Mexico Night Bugs
- Nota Lepidopterologica goes advanced open access with Pensoft Publishers | Blog
- Uncategorized | Blog - Part 22