Leaf-miner: CAT L – The leaf or a Photo required – 
Larval Case: C1 – Distinctive Species – 
– click for General Verification Guidelines | – click for Specific Verification Guidelines 
– Uncertain/Unknown – Insufficient Data 
– Leaf Miner
– difficult to identify – detailed examination required, often a Gen Det and/or specimen and quality photographs are required. Mine Period Additional: Mines August-October.
Mine ID Difficulty:
– Care required in ID process as confusion with similar leaf mines. Quality photos of the mine required. Mine Type/s: Gallery, Blotch
Mine Feeding Method/s: Not Recorded
Mine Comment:
Known for the distinctive mines its larvae create in the leaves of aspen and other poplars. The egg is usually found on the upper-side of the leaf besides a rib. The larva makes a convoluted mine, starting as a narrow gallery is clear with broken linear frass and is a densely winding corridor. widening into a blotch-like gallery on upper-side of the leaf, causing brownish discolouration to that part of the leaf. Found on Populus tremula (Aspen), Populus alba (White Poplar) and Populus canescens (Grey Poplar). Mines shown on Populus tremula (Aspen).
Wyver Lane, Belper – Dave Evans© / Hayfield 13/11/2025 – Christian Heintzen©
Image Gallery
Distribution Map for Stigmella assimilella
↳ 1 from 2025+
↳ from 2020 - 2024
↳ 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 – Stigmella assimilella
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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:
Stigmella assimilella
( data includes both Larvae and Adult Stages )
Monthly Counts By Year: Stigmella assimilella
( data is based on 'Adult' stage records only. )
First/Last Recorded Dates: Stigmella assimilella
Adult-only & Anything [Larvae, Pupae, Adult, Mines]
Shading shows moth presence between dates
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Recordings By Year: Stigmella assimilella
( All data includes both Larvae and Adult Stages )
Annual Growth Rate (AGR): Stigmella assimilella
AGR: 0% | Total % Change: 0%
Stigmella assimilella
Insufficient records/data for an AGR analysis
Stigmella assimilella
Insufficient records/data for a CUSUM analysis
Hectad (10kmx10km) Coverage: Stigmella assimilella
( data includes both Larvae and Adult Stages )
Flight Periods – Indicative –vs– Recorded Data
Stigmella assimilella
Stigmella assimilella
( 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.
Mine Periods – Indicative –vs– Recorded Data
Stigmella assimilella
Stigmella assimilella
( data includes both Larvae and Adult Stages )
Mine 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 mine periods [month/s]. The coloured lines represent the actual months seen mining, from site observation records received between 2020-2025.
Records Behind the Map and Charts - Stigmella assimilella – 1 records available
Listed by Year - descending - scroll across to see all table columns
| Site Name | Tetrad | Date | Count | Stage | Source |
|---|---|---|---|---|---|
| Hayfield-Birch Vale, Sett Valley Trail | SK08D | 13/11/2025 | 1 | Leaf-mine | vc57_irecords_extract |