Plant and Pest Diagnostic Clinic (PPDC.OSU.EDU) received a Dill flower head (Anethum graveolens) sample on July 11th 2023, from a residence in Bluffton, OH with three larvae in it. In comparison, the larvae looked similar to the purple carrot-seed moth, so they were placed in a container until the adults emerged. A few days later, 3 adults emerged and were identified as Depressaria depressana, and the species was not officially recorded from OH. Adult moths were sent to the National Identification Services (NIS) for confirmation. NIS confirmed the moths as Depressaria depressana and reported them as a new state record and Non-quarantine.
The larvae are brown-red in color with irregular light green/white spots on the body. Larvae start webbing in the flower heads and pupate in the umbel. It is reported that caterpillars can feed on flower heads of carrot, parsnip, dill, celery, parsley, coriander, fennel, caraway, and cumin.
(Image by Shannon Bielicke, Johnson Co. Extension Office, IA)
The adult wings are purplish-brown dorsally. The head and thorax are pale. The size of the adult is about 3/8 inch (the scale in the photograph is in mm).
(Image by Suranga Basnagala, The Ohio State University)
A paper published by Landry et al. in 2013, reported a possible occurrence of Depressaria depressana in North America as early as 2008. This is the first report of the purple carrot-seed moth in North America. After that, many photographs of larvae and adults of D. depressana were reported and posted to BugGuide website starting in 2009, but not verified. So far BugGuide has photographs reported from most of the eastern US, including OH.
There are no federal, state, or local regulations related to this species.