Verification

Verification is the process of establishing confirmation that the data is correct and accurate. Two examples of biological record verification are georeference verification (checking the location is correct) and species ID verification (checking the ID is correct).

Verification is important to ensure that biological record databases contain high quality and accurate data, which is therefore more suitable for use in conservation, planning and research. Verifiers should therefore have the expertise to determine if the information provided is likely to be correct.

All earthworm species records (or datasets) submitted to the National Earthworm Recording Scheme (either directly or through iRecord) are assessed before being accepted. The National Earthworm Recording Scheme uses the verification terms used by iRecord and the NBN Atlas (with one exception).

Record verification status terms

Records submitted to the ESB belong to one of three categories (known as verification level 1):

Unconfirmed – The record/dataset has been submitted to the National Earthworm Recording Scheme but has either not been looked at, or a verification decision not yet been reached (for example the verifier may be awaiting further information from the recorder).

Accepted – The record/dataset is accepted as meeting the criteria required for inclusion in the National Earthworm Recording Scheme database.

Not accepted – The record/dataset is not accepted as meeting the criteria required for inclusion in the National Earthworm Recording Scheme database.

These categories are further broken down into 6 sub-categories (known as verification level 2).

Verification Level 1	Verification Level 2	Description
Accepted	Correct	The verifier is able to confirm that the species has been identified correctly, usually on the basis of photo(s) or a voucher specimen.
	Considered correct	The verifier was not able to personally confirm the species identification using photos or a voucher specimen but has a high degree of confidence that the record is likely to be correct, based on a number of criteria (such as determiner experience and use of a suitable ID resource).
Not Accepted	Unable to verify	The verifier has a high degree of confidence that the record is likely to be incorrect based on information provided by recorder (such as photos, identifications resources used and a lack of recorder experience and skill).
	Incorrect	The verifier is able to confirm that the species has been identified incorrectly, usually on the basis of a voucher specimen or, in some cases, a photo of the distinguishing characteristics.
Unconfirmed	Plausible	The record is plausible based on species, date and location, but there is not enough supporting evidence for the possibility of mis-identification to be ruled out. This is not considered as an Accepted record (and would not be exported to the NBN Atlas for those schemes that link directly to NBN). Note: The National Earthworm Recording Scheme does NOT use this verification status.
	Not reviewed	The record has been submitted to the National Earthworm Recording scheme (either directly or through iRecord) but has either not yet been assessed or a verification decision not yet been reached. This is the default status until a verifier has assessed the record.

Verification status assessment criteria

Assessing the verification status of an earthworm identification involves considering a number of criteria. In total there are 8 criteria that are considered.

Criterion A: Voucher specimen availability

Voucher specimens are physical earthworm specimens submitted alongside the record. They can be submitted to verifiers directly or to the Natural History Museum (London). Voucher specimens are not required for records to achieve a Considered correct status.

Criterion B: Record impact on current knowledge base

Some records may have a significant impact on our current knowledge of earthworms and their distributions if they are for species where there is little data currently available (such as rare or very rare species of earthworm) or if they tell us something new about a species (such as being outside of the known geographic range of a species). 

Rare species	Very rare species
Aporrectodea icterica	Aporrectodea cupulifera
Aporrectodea limicola	Dendrobaena pygmaea
Aporrectodea nocturna	Helodrilus oculatus
Dendrobaena attemsi	Kenleenus armadus
Dendrobaena hortensis	Lumbricus friendi
Dendrobaena octaedra	Microscolex phosphoreus
Dendrobaena veneta	Sparganophilus tamesis
Lumbricus festivus
Murchieona muldali

The impact of an individual species record on the current knowledge base is defined as low, medium or high impact as outlined below.

Low Impact	Medium Impact	High Impact
Common or very common species within known geographic range	Common or very common species outside known geographic range	Any species new to a specific country/territory or with previously unrecorded character (such as outside of known size range)
Rare species (where determiner has proven record of successful ID of specific species)	Rare species (where determiner has no proven record of successful ID of specific species)	Very rare species (all records)

•    For medium impact records, suitable photographs illustrating the distinguishing morphological features or a voucher specimen will be required to confirm the species determination. 
•    For high impact records, a voucher specimen will be required to confirm the species determination.

Criterion C: Photograph availability

Photographs can be useful when assessing a species determination, particularly macrophotography of distinguishing morphological features such as the tubercula pubertatis. They can be submitted electronically alongside the record. Photographs are not required for records to achieve a Considered correct status.

Criterion D: Determiner earthworm identification experience

The verifier will try to establish the level of relevant experience the determiner has regarding earthworm identification (or experience of other similarly difficult taxa), such as:

• Completion of an ESB-approved earthworm ID training course.
• Proven experience of successfully determining earthworms where voucher specimens have been confirmed by an expert or verifier.
• Published professional or academic work involving earthworm taxonomy and identification.
• Proven experience of successfully determining similarly difficult to identify taxa.

Criterion E: Features used for identification

In the UK and Ireland, it is possible to identify earthworms to species level based on certain morphological features. However, some features are considered too variable (or too open to interpretation) to be used as reliable identification features.

Suitable features	Unsuitable features
Head (prostomium) type	Length
Male pore position	Diameter
Tubercula pubertatis (TP) presence, shape and position	Pigmentation
Clitellum position	Colour
Setae spacing	Field signs (e.g. middens)
Internal anatomical features (e.g. seminal vesicles, spermathecae, pseudohearts, califerous glands and prostate glands.	Other ecological or behavioural factors such microhabitat observed within, tail flattening or autotomy.

Criterion F: Identification resource used

Sherlock 2018 is the current preferred earthworm identification resource for determining British and Irish earthworms, whereas other accepted identification resources may have some limitations due to recent additions to the British and Irish fauna and/or changes in taxonomy. A list of currently accepted earthworm identification resources is provided below. The use of established reference collections and/or species descriptions is also accepted.

1. Sherlock, E. (2018). Key to the earthworms of the UK and Ireland. 2nd edition. AIDGAP, Field Studies Council, Shrewsbury.
2. Sherlock, E. (2012). Key to the earthworms of the UK and Ireland. AIDGAP, Field Studies Council, Shrewsbury.
   Note: The online ESB Earthworm Identikit based on this ID resource is also considered an accepted resource.
3. Sims, R.W. & Gerard, B.M. (1985). Earthworms. Synopsis of the British fauna (New Series), No. 31 (revision). Revised by Barnes, R.S.K. and Crother, J.H., Field Studies Council, Shrewsbury, 1999.

Species determinations reached using the OPAL earthworm key (and the iSpot key derived from it) will not be accepted (see Limitations of the OPAL Earthworm Guide for Species Identification for more details). 

Criterion G: Specimen suitability

Earthworm specimens must be sufficiently developed and in a suitable condition in order for a record to be accepted. 

Life stage	Suitable specimen	Unsuitable specimen
Adult	Specimen with distinguishing characters intact (all species)		Damaged specimen with distinguishing features missing
Sub-adult	Specimen with distinguishing characters developed (only applicable for some species)		Sub-adult specimen with distinguishing features not yet developed (all species)
Juvenile	None		All specimens (regardless of condition)
Cocoon	None		All specimens (regardless of condition)

Criterion H: Observation method used

Observing earthworms can be difficult, so it is important for the verifier to establish that the identification features used to determine the species were observed using a reliable method. 

Live earthworms are able to move their bodies in numerous ways, including stretching and contracting. This can make counting the segments on a specimen extremely difficult. For this reason, it is recommended that earthworm species determinations are conducted using preserved specimens. All live specimen records will require submission of photographs that clearly evidence the presence of the accepted distinguishing features used to reach a species determination (i.e. the verifier must confirm the species via photographs in order for the record to be accepted).

Many of the features used to determine earthworms to species level are not visible with the naked eye. For this reason, it is recommended that specimens are observed under magnification, preferably using a dissecting microscope. Hand lenses may be suitable for larger specimens, and good quality macrophotography can also be used where all distinguishing features are captured.

How can I get my record verified by a tutor or an expert?

Please submit your record as per the usual submission pathways and the ESB will get in touch. Please note that a tutor or expert may need to inspect the voucher specimen so it’s always useful to retain the preserved specimen for any determinations that you believe may require verification.

If you have any questions relating to the identification of British or Irish earthworms, please contact the Earthworm Society of Britain at ESBenquiries@gmail.com. 

Except where otherwise indicated, this work was created by Keiron Derek Brown on behalf of the Earthworm Society of Britain and is licensed under a Creative Commons Attribution 4.0 International License.