28.014 BF642  –  Oecophoridae –  Oecophorinae – Crassa unitella – Brown Bark Moth – (Hübner, 1796) Adult Micro:  CAT 2 – Confusion Species –       PDF Icon – click for General Verification Guidelines  |   PDF Icon – click for Specific Verification Guidelines
Blue –  Generally Common / Widespread   
Taxonomy:   Micro   >>  Oecophoridae  >> Oecophorinae
Other Name/s: Plain Bark Moth, Golden-brown Tubic
ID Difficulty:  amber  – care required in the identification process, as confusion with similar species is likely – quality photographs required.
Confusion Species:  C.tinctella
ID pointers: Fairly distinctive in appearance. A yellow head and golden brown body and forewings.
Distribution:  Formally Batia unitella – Status unsure, not listed in Harrison & Sterling (1988). Suspect locally common but seems to be widespread across most parts of the county.
Flight Period: June /  July /  August /  –  On the wing in June – August.  Moth Activity: Cathemeral   – and is attracted to light Photographed: Yes –  Photographed By: Tony Davison  © All Rights Reserved
*** Last updated on 6 May 2025 by RP ***
Wingspan: 13-17mm
Food Plant: Larvae feed on fungus on and under bark.
Recorded dates for Common [Blue code Blue-coded] moths are not stored on the website at this current time.

IMAGES BELOW:  Melbourne, Derbyshire – Tony Davison ©

 
 

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Distribution Map for Crassa unitella

Found 173 records
    ↳ 37 from After 2025
    ↳ 49 from 2020 - 2024
    ↳ 87 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.

******* Choose ONLY one at a time, of either Monad, Tetrad or Hectad Distribution - each has it's own set of data. Also, the distribution maps cover ALL recorded data. *******

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.

Land-cover * shows the variety of land-cover within the VC57 area, based on the CORINE (Coordination of Information on the Environment) forty-four thematic classes of land-cover. This will show, to a greater or lesser degree, the number and variety of moths found in different land-cover types. The UK continues to operate within the Copernicus programme, with the UK Centre for Ecology & Hydrology (UKCEH) providing Corine Land Cover (CLC) datasets for the UK and its territories.


NBN Atlas UK Distribution for – Crassa unitella

⚠️ 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.

Visit NBN Site


Monthly Records By Year: Crassa unitella
( data includes both Larvae and Adult Stages )

Monthly Counts By Year: Crassa unitella
( data is based on 'Adult' stage records only. )


First/Last Recorded Dates: Crassa unitella
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: Crassa unitella
( All data includes both Larvae and Adult Stages )
Annual Growth Rate (AGR): Crassa unitella
AGR: 0.79%   |   Total % Change: 18.9%


CUSUM Analysis: Crassa unitella
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 4 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 2008, reaching above average levels. The lowest population point occurred near 2016, 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: Crassa unitella
( data includes both Larvae and Adult Stages )

Flight Periods – Indicative –vs– Recorded Data
Crassa unitella
( 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 - Crassa unitella – 173 records available

Listed by Year - descending - scroll across to see all table columns

Site NameTetradDateCountStageSource
Staunton Harold ReservoirSK32S05/09/20251adultvc57_irecords_extract
BelperSK34N06/08/20251adultvc57_irecords_extract
Jim Mart Nature ReserveSK36S12/08/20251adultvc57_irecords_extract
Cromford MoorSK25X11/08/20251adultvc57_irecords_extract
Bamford, Hope Valley SBE, UKSK28B13/08/20251Adultvc57_irecords_extract
Belper, DerbyshireSK34N17/08/20251adultvc57_irecords_extract
Ingleby Ave, DerbySK33L07/07/20254adultvc57_irecords_extract
Norton Lees, SheffieldSK38L11/07/20252adultvc57_irecords_extract
Norton Lees, SheffieldSK38L12/07/20252adultvc57_irecords_extract
Norton Lees, SheffieldSK38L13/07/20252adultvc57_irecords_extract
Melbourne, DerbyshireSK32X13/07/20252adultvc57_irecords_extract
Ingleby Ave, DerbySK33L16/07/20251adultvc57_irecords_extract
Norton Lees, SheffieldSK38L18/07/20251adultvc57_irecords_extract
Old Marble Mill, Ashford in the WaterSK16Z23/07/20251adultvc57_irecords_extract
Old Marble Mill, Ashford in the WaterSK16Z30/07/20251adultvc57_irecords_extract
Chaddesden, DerbySK33T11/07/20251adultvc57_irecords_extract
Belper, DerbyshireSK34N05/07/20251adultvc57_irecords_extract
Chaddesden, DerbySK33T18/07/20251adultvc57_irecords_extract
Belper, DerbyshireSK34N12/07/20251adultvc57_irecords_extract
Belper, DerbyshireSK34N16/07/20251adultvc57_irecords_extract
Belper, DerbyshireSK34N21/07/20251adultvc57_irecords_extract
Belper, DerbyshireSK34N24/07/20251adultvc57_irecords_extract
Belper, DerbyshireSK34N25/07/20251adultvc57_irecords_extract
Belper, DerbyshireSK34N29/07/20251adultvc57_irecords_extract
Ingleby Ave, DerbySK33L16/06/20251adultvc57_irecords_extract
Norton Lees, SheffieldSK38L17/06/20251adultvc57_irecords_extract
Havercroft RoadSK38L20/06/20251adultvc57_irecords_extract
Norton Lees, SheffieldSK38L21/06/20251adultvc57_irecords_extract
Chaddesden GardenSK33T21/06/20251adultvc57_irecords_extract
Norton Lees, SheffieldSK38L25/06/20251adultvc57_irecords_extract
BelperSK34N25/06/20251adultvc57_irecords_extract
Chaddesden GardenSK33T14/06/20251adultvc57_irecords_extract
Norton Lees, SheffieldSK38L27/06/20251adultvc57_irecords_extract
Norton Lees, SheffieldSK38L30/06/20251adultvc57_irecords_extract
Darwin ForestSK26X30/06/20251adultvc57_irecords_extract
Midway, Derbys.SK32A30/06/20251adultvc57_irecords_extract
Derby DESK33I20/06/20251adultvc57_irecords_extract
DWT Wyver LaneSK34P04/09/20241adultvc57_irecords_extract
King's NewtonSK32Y05/09/20241adultvc57_irecords_extract
Lower Cromford GardenSK25Y02/08/20241adultvc57_irecords_extract
Mickleover gardenSK33C01/08/20241adultvc57_irecords_extract
HathersageSK28F01/08/20241adultvc57_irecords_extract
Norton Lees, Sheffield, UKSK38L17/07/20241Adultvc57_irecords_extract
BelperSK34N17/07/20241adultvc57_irecords_extract
Forbes Hole LNRSK43W19/07/20241adultvc57_irecords_extract
Scalpcliffe roadSK22R30/07/20241adultvc57_irecords_extract
Shirland - Hallfieldgate LaneSK35Z19/07/20241Adultvc57_irecords_extract
Shirland - Hallfieldgate LaneSK35Z30/07/20241Adultvc57_irecords_extract
West Park Fox Covert LNRSK43W31/07/20241adultvc57_irecords_extract
Chaddesden, DerbySK33T18/07/20241adultvc57_irecords_extract
Norton Lees, Sheffield (VC)SK38L29/07/20243adultvc57_irecords_extract
Norton Lees, Sheffield (VC)SK38L19/07/20243adultvc57_irecords_extract
Norton Lees, Sheffield (VC)SK38L22/07/20241adultvc57_irecords_extract
Norton Lees, Sheffield (VC)SK38L28/07/20241adultvc57_irecords_extract
Birch ValeSK08I31/07/20241adultvc57_irecords_extract
King's NewtonSK32Y29/07/20241adultvc57_irecords_extract
Ashford Marble MillSK16Z25/07/20241adultvc57_irecords_extract
Ashford Marble MillSK16Z30/07/20241adultvc57_irecords_extract
Derby DESK33I30/07/20241adultvc57_irecords_extract
Derby DESK33I19/07/20241adultvc57_irecords_extract
Inkersall gardenSK47C26/06/20241adultvc57_irecords_extract
South WoodSK31U27/06/20241adultvc57_irecords_extract
Staveley DerbyshireSK47H03/09/20231adultvc57_irecords_extract
Allestree, Derby, Elm GroveSK34K02/09/20231adultvc57_irecords_extract
Havercroft RoadSK38L10/08/20231Adultvc57_irecords_extract
Long Eaton, Marlborough RoadSK43X07/07/20231adultvc57_irecords_extract
Woodland AveSK43R07/07/20234adultvc57_irecords_extract
Belper GardenSK34P07/07/20231adultvc57_irecords_extract
BelperSK34N17/07/20231adultvc57_irecords_extract
Allestree, Derby, Elm GroveSK34K01/08/20222adultvc57_irecords_extract
Allestree, Derby, Elm GroveSK34K01/08/20222adultvc57_irecords_extract
Staveley DerbyshireSK47H12/07/20221adultvc57_irecords_extract
Woodland AveSK43R19/07/20222Adultvc57_irecords_extract
Midway, Derbys.SK32A10/08/20211adultvc57_irecords_extract
Woodland AveSK43R02/07/20211adultvc57_irecords_extract
Woodland AveSK43R18/07/20211adultvc57_irecords_extract
Woodland AveSK43R20/07/20211adultvc57_irecords_extract
Marlborough Road, Long Eaton, DerbysSK43X07/08/20201adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y14/08/20201Adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y05/08/20201Adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y07/08/20203Adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y12/08/20204Adultvc57_irecords_extract
Birch ValeSK08I11/08/20201adultvc57_irecords_extract
Woodland AveSK43R29/07/20201adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y12/07/20201Adultvc57_irecords_extract
Woodland AveSK43R30/06/20201adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y22/08/20191Adultvc57_irecords_extract
Welbeck Drive, WingerworthSK36T26/08/20191adultDanes_2019-2021
Norton LeesSK38L03/08/20192adultDanes_2019-2021
Norton LeesSK38L02/08/20191adultDanes_2019-2021
Marlborough Road, Long Eaton, DerbysSK43X16/07/20191adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y15/07/20193Adultvc57_irecords_extract
Long Eaton - Marlborough RoadSK43X04/07/20191Adultvc57_irecords_extract
Pleasley Pit CP, PleasleySK46X27/07/20191adultDanes_2019-2021
Norton LeesSK38L25/07/20193adultDanes_2019-2021
Lang Rd, Alvaston, DerbySK33R24/07/20191adultDanes_2019-2021
Wood Lane, Newhall, SwadlincoteSK22V18/07/20192adultDanes_2019-2021
Norton LeesSK38L16/07/20195adultDanes_2019-2021
Norton LeesSK38L15/07/20193adultDanes_2019-2021
Wood Lane, Newhall, SwadlincoteSK22V12/07/20191adultDanes_2019-2021
Norton LeesSK38L05/07/20192adultDanes_2019-2021
Main Street, Kings NewtonSK32Y19/07/20181Adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y18/07/20181Adultvc57_irecords_extract
Norton LeesSK38L01/07/20181Adultvc57_irecords_extract
Trowell Marsh LNRSK43U07/07/20181adultvc57_irecords_extract
Norton LeesSK38L06/07/20183Adultvc57_irecords_extract
Norton LeesSK38L29/06/20181Adultvc57_irecords_extract
Shirland - Hallfieldgate LaneSK35Z06/07/20172adultvc57_irecords_extract
Norton Lees gardenSK38L23/08/20161not recordedvc57_irecords_extract
Sheffield, England, United KingdomSK38L19/07/20161Adultvc57_irecords_extract
Backgarden MarehaySK34Z20/07/20161adultvc57_irecords_extract
Backgarden MarehaySK34Z23/07/20162adultvc57_irecords_extract
Shirland - Hallfieldgate LaneSK35Z22/07/20161Adultvc57_irecords_extract
Norton Lees gardenSK38L18/07/20161not recordedvc57_irecords_extract
Norton Lees gardenSK38L21/07/20161not recordedvc57_irecords_extract
Norton Lees gardenSK38L23/07/20162not recordedvc57_irecords_extract
Wood Lane,Newhall,SwadlincoteSK22V21/07/20161Adultvc57_danes_bc_data
Waingroves Wood Moth and Bat EventSK44E08/08/20151adultvc57_irecords_extract
Waingroves Wood Moth and Bat EventSK44E08/08/20151adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y06/08/20141Adultvc57_irecords_extract
Backgarden MarehaySK34Z10/07/20141adultvc57_irecords_extract
Wood Lane,Newhall,SwadlincoteSK22V18/07/20141Adultvc57_danes_bc_data
Backgarden MarehaySK34Z09/07/20131adultvc57_irecords_extract
Backgarden MarehaySK34Z23/07/20131adultvc57_irecords_extract
Backgarden MarehaySK34Z26/07/20132adultvc57_irecords_extract
Backgarden MarehaySK34Z12/08/20121adultvc57_irecords_extract
Bamford St,RipleySK34Z12/08/20121Adultvc57_danes_bc_data
Backgarden MarehaySK34Z17/07/20121adultvc57_irecords_extract
Carr WoodSK45A22/07/20123adultvc57_irecords_extract
Carr WoodSK45A22/07/20121adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y25/07/20122Adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y26/07/20121Adultvc57_irecords_extract
Bamford St,RipleySK34Z17/07/20121Adultvc57_danes_bc_data
Carr Wood, RipleySK45A22/07/20124Adultvc57_danes_bc_data
Main St,Kings Newton,MelbourneSK32Y25/07/20122Adultvc57_danes_bc_data
Main St,Kings Newton,MelbourneSK32Y26/07/20121Adultvc57_danes_bc_data
Backgarden MarehaySK34Z01/08/20111adultvc57_irecords_extract
Bamford St,RipleySK34Z01/08/20111Adultvc57_danes_bc_data
Rose Av,ClowneSK57D11/07/20101Adultvc57_danes_bc_data
Main Street, Kings NewtonSK32Y02/08/20082Adultvc57_irecords_extract
Robin WoodSK32M03/08/20083Adultvc57_irecords_extract
Robin Wood (central area)SK32M04/08/20083Adultvc57_danes_bc_data
Bristol Rd,IlkestonSK44R05/08/20081Adultvc57_danes_bc_data
Calke Park Ticknall Lime YardsSK32R03/08/20073adultvc57_irecords_extract
Bristol Rd,IlkestonSK44R10/08/20071Adultvc57_danes_bc_data
DovedaleSK15K10/08/20071Adultvc57_danes_bc_data
Ticknall Limeyards,TicknallSK32R03/08/20073Adultvc57_danes_bc_data
Calke Park Ticknall Lime YardsSK32R22/07/20071adultvc57_irecords_extract
Ticknall Limeyards,TicknallSK32R22/07/20071Adultvc57_danes_bc_data
Kedleston ParkSK34A12/08/20061not recordedvc57_irecords_extract
Kedleston Park (Hall garden), DerbySK34A12/08/20061Adultvc57_danes_bc_data
DovedaleSK15L21/07/20061Adultvc57_danes_bc_data
Main Street, Kings NewtonSK32Y11/07/20051Adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y13/07/20051Adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y21/07/20052Adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y26/07/20051Adultvc57_irecords_extract
Main St,Kings Newton,MelbourneSK32Y13/07/20051Adultvc57_danes_bc_data
Foremark Resr, TicknallSK32H09/07/20051Adultvc57_danes_bc_data
Main St,Kings Newton,MelbourneSK32Y11/07/20051Adultvc57_danes_bc_data
Main St,Kings Newton,MelbourneSK32Y21/07/20052Adultvc57_danes_bc_data
Main St,Kings Newton,MelbourneSK32Y26/07/20051Adultvc57_danes_bc_data
Main Street, Kings NewtonSK32Y01/08/20041Adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y04/08/20041Adultvc57_irecords_extract
Main St,Kings Newton,MelbourneSK32Y01/08/20041Adultvc57_danes_bc_data
Main St,Kings Newton,MelbourneSK32Y04/08/20041Adultvc57_danes_bc_data
Spinney Hill,MelbourneSK32X06/08/20041Adultvc57_danes_bc_data
Edgecote Drive,Newhall,SwadlincoteSK22V07/08/20041Adultvc57_danes_bc_data
Main Street, Kings NewtonSK32Y13/07/20041Adultvc57_irecords_extract
Main Street, Kings NewtonSK32Y27/07/20043Adultvc57_irecords_extract
Main St,Kings Newton,MelbourneSK32Y13/07/20041Adultvc57_danes_bc_data
Main St,Kings Newton,MelbourneSK32Y27/07/20043Adultvc57_danes_bc_data
Rosliston National Forest CentreSK21N01/08/20031Adultvc57_irecords_extract
Rosliston (National Forest Centre), SwadlincoteSK21N01/08/20031Adultvc57_danes_bc_data

 
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