Species Account

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Summary Data

Season (Adult / Immature):

National Status: Common

Local Status: Fairly common and widespread resident.

Local Record: Grade 1   See here for explanation

Flight time: One generation, Jul-Oct.

Forewing: 17-21mm.

Foodplant: Ash.

IMPORTANT - Please note that the maps and accounts are provisional, subject to change and further update.  The whole dataset still needs to go through the final verification process and it is likely that a very small number of records will not satisfy the present requirements and there are other records that have not been formally submitted.  The information is for guidance only.

Record breakdown:

Year first recorded192919831929
Year last recorded201120112011
Number of records1316562744
Number of individuals2832675798
Unique positions1506312
Unique locations1246260
Adult records1252522608
Immature records000

For the region, we have a total of 2744 records from 260 sites. Earliest record on file is in 1929.


1914 Dusky Thorn 03
© Julian Francis
1914 Dusky Thorn 02
© Julian Francis
1914 Dusky Thorn 01
© Tom Morris

Species Account

Similar species: 1912 Ennomos quercinaria (August Thorn) and 1915 Ennomos erosaria (September Thorn).

For further information refer UK Moths.

Davey, P., 2009: A species occurring across England and Wales, the larva feeding on ash (Fraxinus spp.). In Dorset, the moth is widely distributed across the county wherever ash is found, but it is usually at low density and seldom common. It is found in ash-dominated woods that grow on chalky soil, and in open localities where ash grows in relative isolation.

See background to species accounts.  Index of Vernacular names - Search - Random Species