Synonyms and other taxonomic changes
Ponometia erastrioides (Guenée, 1852)
Acontia erastrioides
Tarachidia erastrioides
Phylogenetic sequence # 931319
Identification
Adult - forewing white with large diagonal blackish patch in distal half, but not reaching apex; no greenish-yellow shading; orbicular spot, tiny, black; reniform spot obscured by mottling hindwing whitish basally with grayish-brown shading distally
Larva - Elongate, slender, tan to nearly black, or less commonly, pale green. Dorsum of A1-A3 with paired black spots to either side of midline. A8 humped. Fine white spiracular stripe zigzagging along abdomen with spurs extending along outer face of prolegs on A5 and A6. Head with extensive black patterning; cheek with divided white patch. Larva under 2.5 cm
Range
eastern United States and southcentral Canada (Quebec, Ontario, Saskatchewan)
Habitat
fields, waste places, riparian areas where food plants grow; adult is attracted to light
Season
adults fly from May to September
Food
larvae feed on ragweed (Ambrosia spp.)
Remarks
Larvae are quick to regurgitate a deep green vomit if handled.
See Also
Ponometia binocula has more uniform yellowish-green color in distal half of forewing, and mostly white hindwing
Olive-shaded Bird Dropping Moth (
Ponometia candefacta) has greenish-yellow shading, and its dark distal patch reaches the forewing apex
(
compare images of all three species)
Ponometia elegantulus has a paler distal half of forewing
other genera in the tribe
Acontiini have a similar overall appearance
Larva - Middle instars with warted dorsal pinacula, especially over A1 and A2 (lower inset), approaching appearance of some Spragueia. Similarly patterned Olive-shaded Bird-dropping Moth (T. candefacta) lime-green and lacking black patterning over head capsule of Small Bird-dropping Moth. The caterpillar may also be confused with those of various Spragueia, and especially that of the Common Spragueia (Spragueia leo) which co-occurs with it on ambrosia. It is a bit smaller, lacks brown pattern elements, and the pale cheek patch is more hemispherical and not as longitudinally elongate as in the Small Bird-dropping Moth.
Internet References
live adult images and common name reference [Small Bird Dropping Moth] (Larry Line, Maryland)
pinned adult image plus common name reference [Small Bird Lime Moth], description, similar species, distribution, food plants (Gerald Fauske, Moths of North Dakota)