– click for Adult Macro Verification Guidelines
– Rare / Uncommon / Scarce
– care required in the identification process, as confusion with similar species is likely – quality photographs required. Confusion Species: Purple clay, Small Square-spot, Ingrailed Clay
ID pointers: See ID Guide below provided by Christian Heintzen©
Distribution: (Last record: 25 July 2025 at Glossop ) – Widely distributed across the upland moorland areas of North Derbyshire, but not in large numbers. The distribution seems to be concentrated around the central part of the county, with some records from further north (Buxton).
*** Last updated on 2 October 2025 by RP ***
Forewing: 15-18mm
Last Recorded Year: 2025
Last Recorded By – Christian Heintzen
Last Recorded General Area – Glossop
Selected Images: ID guide kindly provided by Christian Heintzen © / Images Glossop & Long Clough – Christian Heintzen© / Glossop (July 2025) Christian Heintzen©
Image Gallery
No gallery images found for this moth.
Distribution Map for Diarsia dahlii
Found 82 records
↳ 2 from After 2025
↳ 16 from 2020 - 2024
↳ 64 from Before 2020
↳ 2 from After 2025
↳ 16 from 2020 - 2024
↳ 64 from Before 2020
If the Map Layers function fails, just refresh the page and it should be OK after. Use the +- zoom on the top left, or on a tablet, use two fingers to zoom. Remember, the last layer you ticked is the one which displays the popup information - they sit on top of each other - de-select then re-select, to see the popup values.
Bedrock Geology ** indirectly affects moth distribution by influencing the type of habitat and food plants available in an area. In turn, this may affect the types of moths that can thrive, or where they can most likely be found.
NBN Atlas UK Distribution for – Diarsia dahlii
⚠️ Please wait for the map to load fully – do not click the link shown.
Note – the NBN Atlas datasets are listed in the map below and vary in their currency (uptodateness) – however,
the map does give a general indication of the moth's distribution across the UK.
Monthly Records By Year:
Diarsia dahlii
( data includes both Larvae and Adult Stages )
Monthly Counts By Year: Diarsia dahlii
( data is based on 'Adult' stage records only. )
First/Last Recorded Dates: Diarsia dahlii
Adult-only & Anything [Larvae, Pupae, Adult, Mines]
Shading shows moth presence between dates
Click the colour discs below to Select/De-select as Required
Recordings By Year: Diarsia dahlii
( All data includes both Larvae and Adult Stages )
Annual Growth Rate (AGR): Diarsia dahlii
AGR: 1.86% | Total % Change: 50%
CUSUM Analysis: Diarsia dahlii
About this chart: CUSUM (Cumulative Sum) charts track long-term trends in moth populations [ filtered by 'Adult' and 'Mine' life stages ] by showing whether each year’s counts are above or below the historical average. Even small shifts build up over time, making trends of growth, stability, or decline easier to see. CUSUM highlights trend-consistency — asking: “Across the years, have moth counts mostly stayed above or below average?”
The data sample has 9 gap year/s here (zero records) between 2000 and 2025. The moth may have been present in those gap years, but no data was available. Too many year-gaps may exaggerate or skew the chart.
Counts for the current year (2025) are pro-rated based on data available up to month 8 (August) to provide a full-year equivalent.
ⓘ
Purple line rises = years better than average; falls = years worse than average.
Peak (best year)
Trough (worst year)
Growth periods
Decline periods
Population peaked around 2009, reaching above average levels. The lowest population point occurred near 2007, showing a significant decline.
What the Y-axis "Cumulative Deviation" means: Cumulative Deviation shows the running total of how each year’s moth population count differs from the long-term average. i
Hectad (10kmx10km) Coverage: Diarsia dahlii
( data includes both Larvae and Adult Stages )
Flight Periods – Indicative –vs– Recorded Data
Diarsia dahlii
Diarsia dahlii
( data includes Adult Stage only )
Flight Period chart – the grey hatched area above, which can cross one or more months, pictorially represents the best guess we have for this moth's flight periods [month/s]. The coloured lines represent the actual months seen in flight, from site observation records received between 2020-2025.
Records Behind the Map and Charts - Diarsia dahlii – 82 records available
Listed by Year - descending - scroll across to see all table columns
| Site Name | Tetrad | Date | Count | Stage | Source |
|---|---|---|---|---|---|
| Cromford Moor | SK25X | 21/08/2025 | 2 | adult | vc57_irecords_extract |
| Glossop, Hague Street, Hay Meadow | SK09G | 25/07/2025 | 1 | adult | vc57_irecords_extract |
| Glossop, Gnat Hole Rough Fields | SK09L | 01/09/2024 | 1 | adult | vc57_irecords_extract |
| Longdendale, Wildboar Clough Woodland | SK09U | 03/09/2024 | 1 | adult | vc57_irecords_extract |
| Longdendale, Wildboar Clough Woodland | SK09U | 03/09/2024 | 1 | adult | vc57_irecords_extract |
| Glossop, Shawmoor Plantation | SK09G | 04/09/2024 | 2 | adult | vc57_irecords_extract |
| Derbyshire Wild Life Trust Long Clough | SK09G | 23/08/2024 | 1 | adult | vc57_irecords_extract |
| Derbyshire Wild Life Trust Long Clough | SK09G | 31/08/2024 | 2 | adult | vc57_irecords_extract |
| High Leas Farm, Riber | SK35D | 24/08/2024 | 1 | adult | vc57_irecords_extract |
| Lower Cromford Garden | SK25Y | 23/08/2023 | 1 | adult | vc57_irecords_extract |
| Derbyshire Wild Life Trust Long Clough | SK09G | 11/08/2023 | 1 | adult | vc57_irecords_extract |
| Glossop, Gnat Hole Rough Fields | SK09L | 21/08/2023 | 1 | adult | vc57_irecords_extract |
| Glossop, Shawmoor Plantation | SK09F | 23/08/2023 | 11 | adult | vc57_irecords_extract |
| Lower Cromford Garden | SK25Y | 07/09/2022 | 1 | adult | vc57_irecords_extract |
| Glossop, Shawmoor Plantation | SK09F | 06/09/2022 | 1 | adult | vc57_irecords_extract |
| Glossop, Shawmoor Plantation | SK09F | 18/09/2022 | 1 | adult | vc57_irecords_extract |
| Glossop, Shawmoor Plantation | SK09F | 19/09/2022 | 2 | adult | vc57_irecords_extract |
| Hathersage, Derbyshire, UK | SK28F | 29/07/2022 | 1 | adult | vc57_irecords_extract |
| Not given | SK43W | 27/09/2019 | 2 | Adult | vc57_irecords_extract |
| Birch Vale | SK08I | 05/08/2019 | 1 | adult | vc57_irecords_extract |
| Darley Dale (site not precise) | SK26R | 01/08/2018 | 1 | Adult | vc57_danes_bc_data |
| Darley Dale (site not precise) | SK26R | 01/07/2017 | 1 | Adult | vc57_danes_bc_data |
| Jim Mart Nature Reserve | SK36S | 23/08/2016 | 1 | Adult | vc57_irecords_extract |
| School Close,Parkway Gardens,Darley Dale | SK26R | 11/09/2013 | 2 | Adult | vc57_danes_bc_data |
| School Close,Parkway Gardens,Darley Dale | SK26R | 11/09/2013 | 2 | Adult | vc57_danes_bc_data |
| Yew Tree Farm | SK36H | 06/07/2013 | 1 | adult | vc57_irecords_extract |
| Beeley Moor (Slagmill Plantation) | SK36E | 03/09/2012 | 1 | Adult | vc57_danes_bc_data |
| The Mays,Malthouse Lane,Froggatt | SK27N | 02/09/2012 | 1 | Adult | vc57_danes_bc_data |
| Welbeck Drive,Wingerworth | SK36T | 04/09/2012 | 1 | Adult | vc57_danes_bc_data |
| Beeley Moor (Slagmill Plantation) | SK36E | 03/09/2012 | 1 | Adult | vc57_danes_bc_data |
| The Mays,Malthouse Lane,Froggatt | SK27N | 02/09/2012 | 1 | Adult | vc57_danes_bc_data |
| The Mays,Malthouse Lane,Froggatt | SK27N | 11/08/2012 | 1 | Adult | vc57_danes_bc_data |
| The Mays,Malthouse Lane,Froggatt | SK27N | 11/08/2012 | 1 | Adult | vc57_danes_bc_data |
| Cross Green Cottages,Flint Lane,South Darley | SK26Q | 03/09/2011 | 1 | Adult | vc57_danes_bc_data |
| School Close,Parkway Gardens,Darley Dale | SK26R | 13/09/2011 | 1 | Adult | vc57_danes_bc_data |
| School Close,Parkway Gardens,Darley Dale | SK26R | 14/08/2011 | 1 | Adult | vc57_danes_bc_data |
| School Close,Parkway Gardens,Darley Dale | SK26R | 26/08/2011 | 1 | Adult | vc57_danes_bc_data |
| Cross Green Cottages,Flint Lane,South Darley | SK26Q | 07/09/2009 | 1 | Adult | vc57_danes_bc_data |
| Flash Lane,Beeley Moor | SK26X | 14/08/2009 | 1 | Adult | vc57_danes_bc_data |
| Flash Lane,Beeley Moor | SK26X | 07/08/2009 | 7 | Adult | vc57_danes_bc_data |
| Flash Lane,Beeley Moor | SK26X | 29/08/2008 | 23 | Adult | vc57_danes_bc_data |
| Far Cross,Cavendish Park,Matlock | SK36A | 26/08/2008 | 1 | Adult | vc57_danes_bc_data |
| Cross Green Cottages,Flint Lane,South Darley | SK26Q | 24/08/2008 | 1 | Adult | vc57_danes_bc_data |
| Glossop (Shire Hill Quarry) | SK09M | 22/07/2008 | 1 | Adult | vc57_danes_bc_data |
| Cross Green Cottages,Flint Lane,South Darley | SK26Q | 23/08/2007 | 1 | Adult | vc57_danes_bc_data |
| The Hollies,Station Rd,Darley Dale | SK26R | 23/07/2007 | 1 | Adult | vc57_danes_bc_data |
| Cross Green Cottages,Flint Lane,South Darley | SK26Q | 21/09/2006 | 1 | Adult | vc57_danes_bc_data |
| Cross Green Cottages,Flint Lane,South Darley | SK26Q | 05/08/2006 | 1 | Adult | vc57_danes_bc_data |
| Cross Green Cottages,Flint Lane,South Darley | SK26Q | 22/08/2006 | 1 | Adult | vc57_danes_bc_data |
| Flash Lane,Beeley Moor | SK26X | 16/07/2006 | 3 | Adult | vc57_danes_bc_data |
| Cross Green Cottages,Flint Lane,South Darley | SK26Q | 04/09/2004 | 1 | Adult | vc57_danes_bc_data |
| The Hollies,Station Rd,Darley Dale | SK26R | 07/08/2003 | 1 | Adult | vc57_danes_bc_data |
| Cross Green Cottages,Flint Lane,South Darley | SK26Q | 16/08/2003 | 1 | Adult | vc57_danes_bc_data |
| School Close,Parkway Gardens,Darley Dale | SK26R | 14/09/1999 | 1 | Adult | vc57_danes_bc_data |
| Stocksmoor Farm, Ashover Rd, Old Tupton | SK36S | 11/08/1997 | 5 | Adult | vc57_danes_bc_data |
| Beeley Lodge, Chatsworth | SK26U | 04/08/1982 | 1 | Adult | vc57_danes_bc_data |
| Beeley Lodge, Chatsworth Park | SK26U | 04/08/1982 | 1 | Adult | vc57_danes_bc_data |
| Slagmill Plantation,Beeley Moor | SK36E | 31/08/1979 | 1 | Adult | vc57_danes_bc_data |
| Hopton Wood Quarry (site not precise) | SK25M | 28/08/1970 | 1 | Adult | vc57_danes_bc_data |
| Beeley Moor, Beeley (site not precies) | SK26Z | 10/08/1968 | 1 | Adult | vc57_danes_bc_data |
| Beeley Moor, Beeley (site not precise) | SK26Z | 10/08/1968 | 1 | Adult | vc57_danes_bc_data |
| Gladwin's Mark, Beeley Moor | SK36D | 01/09/1964 | 1 | Adult | vc57_danes_bc_data |
| Moorend, Beeley, Matlock | SK26T | 25/08/1959 | 2 | Adult | vc57_danes_bc_data |
| Moorend, Beeley, Matlock | SK26T | 20/08/1959 | 2 | Adult | vc57_danes_bc_data |
| Moorend, Beeley, Matlock | SK26T | 22/08/1959 | 1 | Adult | vc57_danes_bc_data |
| Moorend, Beeley | SK26T | 22/08/1959 | 1 | Adult | vc57_danes_bc_data |
| Moorend, Beeley | SK26T | 25/08/1959 | 2 | Adult | vc57_danes_bc_data |
| Moorend, Beeley | SK26T | 20/08/1959 | 2 | Adult | vc57_danes_bc_data |
| Beeley, Matlock | SK26T | 06/08/1957 | 1 | Adult | vc57_danes_bc_data |
| Beeley | SK26T | 06/08/1957 | 1 | Adult | vc57_danes_bc_data |
| Froggatt (site not precise) | SK27N | 28/08/1954 | 1 | Adult | vc57_danes_bc_data |
| Froggatt (site not precise) | SK27N | 28/08/1954 | 1 | Adult | vc57_danes_bc_data |
| Littleover, Derby (site not precise) | SK33G | 01/01/1951 | 1 | Adult | vc57_danes_bc_data |
| Littleover, Derby (site not precise) | SK33G | 01/01/1951 | 1 | Adult | vc57_danes_bc_data |
| Froggatt (site not precise) | SK27N | 28/08/1948 | 1 | Adult | vc57_danes_bc_data |
| Froggatt (site not precise) | SK27N | 28/08/1948 | 1 | Adult | vc57_danes_bc_data |
| Darley Dale (site not precise) | SK26R | 01/08/1918 | 1 | Adult | vc57_danes_bc_data |
| Darley Dale (site not precise) | SK26R | 01/07/1917 | 1 | Adult | vc57_danes_bc_data |
| Bakewell (site not precise) | SK26J | 01/01/1894 | 1 | Adult | vc57_danes_bc_data |
| Bakewell (site not precise) | SK26J | 01/01/1894 | 1 | Adult | vc57_danes_bc_data |
| Derbyshire (site not precise) | SK33L | 01/01/1870 | 1 | Adult | vc57_danes_bc_data |
| Derbyshire (site not precise) | SK33L | 01/01/1800 | 1 | Adult | vc57_danes_bc_data |