70.012 BF1711 – Treble Brown Spot – Idaea trigeminata – (Haworth, 1809)
Adult Macro: CAT 2 – Can be confused with other species – Good photographs may be required – 
– click for Adult Macro Verification Guidelines
– click for Adult Macro Verification Guidelines
– Significant Record / Very Rare / Vagrant
– care required in the identification process, as confusion with similar species is likely – quality photographs required. Confusion Species: Single-dotted Wave; Small Fan-foot
ID pointers: Unmistakable and strikingly marked – as the name suggests, there are three brown spots in the lower area of the trailing edge of the forewing.
Distribution: (First record: 1980 ) – (Last record: 5 July 2025 at Darwin Forest, Matlock ) – Current status unknown possibly a vagrant – 1 record in 1980. During recent moth record verification, two 2023 records were discovered from Darwin Forest, near Matlock by Dave Evans. One on 26/07/2023 & one on 27/7/2023. Possible re-catch of the same moth. These are the first reported since 1980. Another record from Darwin Forest on 5/7/2025 (seems this species maybe established at this site albeit a small isolated population)
General Comment: None *** Last updated on 13 January 2026 by TD ***
Forewing: 10-11mm
Last Recorded Year: 2025
First Recorded Year: 1980
Last Recorded By – Dave Evans
Last Recorded General Area – Darwin Forest, Matlock
Selected Images: Darwin Forest – 26/7/2023 – Dave Evans © Darwin Forest (2025) – Dave Evans©
Image Gallery
No gallery images found for this moth.
Temporal Distribution Chart
Adults: (between 1990 - 2025)
(click legend below to show/hide datasets)
This chart summarises all available historical occurrence records collated by ISO week of the year. It reflects recorder effort and sampling distribution as well as true biological activity, and should be interpreted as an indicative pattern of seasonal occurrence rather than a statistically controlled abundance or phenology model.
Distribution Map for Idaea trigeminata
Found 7 records
↳ from 2026+
↳ 4 from 2020 - 2025
↳ 3 from Before 2020
↳ from 2026+
↳ 4 from 2020 - 2025
↳ 3 from Before 2020
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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 – Idaea trigeminata
⚠️ 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:
Idaea trigeminata
( data includes both Larvae and Adult Stages )
Monthly Counts By Year:
Idaea trigeminata
( data is based on 'Adult' stage records only )
First/Last Recorded Dates: Idaea trigeminata
Adult-only & Anything [Larvae, Pupae, Adult, Mines]
Shading shows moth presence between dates
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Recordings By Year: Idaea trigeminata
( All data includes both Larvae and Adult Stages )
Annual Growth Rate (AGR): Idaea trigeminata
AGR: 0% | Total % Change: 0%
Hectad (10kmx10km) Coverage: Idaea trigeminata
( data includes both Larvae and Adult Stages )
Flight Periods – Indicative –vs– Recorded Data
Idaea trigeminata
Idaea trigeminata
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 2020-2026.
Records Behind the Map and Charts - Idaea trigeminata – 7 records available
Listed by Year - descending - scroll across to see all table columns
| Site Name | Tetrad | Date | Count | Stage | Recorder | Source | RecordKey |
|---|---|---|---|---|---|---|---|
| Darwin Forest | SK26X | 05/07/2025 | 1 | adult | Evans, Dave | vc57_irecords_extract | iBRC43066079 |
| Darwin Forest | SK26X | 27/06/2023 | 1 | adult | Evans, Dave | vc57_irecords_extract | iBRC35295876 |
| Darwin Forest | SK26X | 26/06/2023 | 1 | adult | Evans, Dave | vc57_irecords_extract | iBRC35295683 |
| Belper | SK34U | 12/06/2023 | 1 | adult | Evans, Dave | vc57_irecords_extract | iBRC35295143 |
| The Meads, Shipley Park, Heanor | SK44H | 13/07/2019 | 1 | adult | COX, Mr K. | Danes_2019-2021 | 1395 |
| Johnnygate, Common Side, Chesterfield | SK37C | 01/08/1990 | 1 | Adult | VC57 Derbyshire Recorder | vc57_danes_bc_data | LC000334001OHKZ5 |
| Johnnygate, Common Side, Chesterfield | SK37C | 14/07/1990 | 1 | Adult | VC57 Derbyshire Recorder | vc57_danes_bc_data | LC000334001OIUJE |