Search for the Silver Colonel

Silver Colonel soldierfly

Photo by Simon Knott

The Silver Colonel soldierfly (Odontomyia argentata) is a rare species with less than two hundred records on the recording scheme database. It has been recorded from 23 vice-counties altogether, all but two of which have records from this century. Encouragingly, there have been recent indications of a spread in range, with new county records from North Devon, Worcestershire and Shropshire within the last five years. Even so, the species is known from relatively few locations and is vulnerable to loss or declining condition of its wetland habitats, and we're keen to monitor how it is doing.

If you find this species please do add the records to iRecord, preferably with a photo if you can, or send them in to the scheme via one of the other routes. If you visit one of the known sites and don't find the fly please let us know that as well. Help with identification is always available via the soldierflies Facebook group, Twitter, or on iSpot.

When to look

Odontomyia argentata flies early in the year, starting in mid-April but with the majority of records in May, fading out in the first week of June.

Phenology chart

 

How to recognise it

It is a species found in fens and marshes, where its larvae have been found in shallow pools and ditches. The adults are slow-moving flies, like most soldierflies, and can be found sitting on the vegetation or visiting flowers, including hawthorn and willow catkins. Odontomyia argentata is reasonably easy to recognise, especially in the male which has the distinctive silvery hairs on its abdomen that give the species its name. The hairs can appear dull from some angles, so try to get a view of it in good light, and if photographing take shots from several angles. Many thanks to Graham Calow for the images below (to which I've added annotations). More of Graham's photos can be seen at NatureSpot, and see also Steven Falk's Flick collection for this species.

identification features

 

Where to look

It is worth looking out for Odontomyia argentata in any fen, marsh or reedbed site in southern England, and also in wet woodlands if they have clearings and pools. Look around the edges of shallow pools and ditches, and on nearby flowers. Andrew Jukes reports finding one in a very small fen next to a car park in Bristol, so don't rule out tiny sites!

The map below shows all the 10km squares for which the recording scheme has records. There may be records missing from the scheme database, either because they haven't been sent it, or are in the backlog waiting to be dealt with - if you know of records that aren't shown on this map please get in touch. There are a few additional records (including one in south Wales) on the NBN Atlas.

Here are the records summarised by vice-county, with the most recently recorded counties first.

Vice-counties with records of Odontomyia argentata

Vice-county Records Earliest Latest
Bedfordshire 3 1944 2022
Cambridgeshire 9 1917 2022
Dorset 2 1947 2022
East Norfolk 36 1924 2022
North Somerset 6 1927 2022
Shropshire 1 2022 2022
South Hampshire 22 1989 2022
South Lincolnshire 3 2017 2022
West Norfolk 7 1948 2022
Worcestershire 1 2022 2022
Berkshire 22 1985 2021
Leicestershire 6 2014 2019
North Devon 2 2019 2019
East Suffolk 6 1943 2018
Huntingdonshire 3 1966 2017
Hertfordshire 2 2014 2016
Surrey 7 1948 2016
West Suffolk 6 1909 2016
West Sussex 1 2016 2016
Warwickshire 1 2013 2013
North Essex 3 1921 2004
North Hampshire 4 1970 1999
North Wiltshire 1 1996 1996
West Kent 1 1948 1948
Middlesex 2 1805 1926
East Sussex 1 1860 1860