|Missing carabids is intended to be a series of notes collating information on carabid species which have not been recorded in Britain for a while. Some may actually have gone extinct but many are best regarded as “missing” and could be rediscovered with some targeted effort. This sheet provides the background information for someone to target Agonum chalconotum. If it does still survive in Britain, there is every likelihood that it is a threatened species: its rediscovery would probably need to be followed up by some dedicated conservation action.|
The species now known as Agonum chalconotum was known to British coleopterists for many years as Agonum sahlbergi (more recently emended to Agonum sahlbergii).
Agonum chalconotum was first collected in Britain by Mr Bishop in about 1864 “in some numbers on the edge of a sandy bank on the north side of the Clyde a few yards west of Dunglass Castle” (Murphy, 1918). Dunglass Castle is at NS437735 (Dunbartonshire VC99) on a stretch of the coast which the map shows to have been reclaimed and developed but there appears to be relatively natural coastline very nearby. Mr Henderson subsequently took a few specimens, presumably by visiting the same locality and these found their way into Dr Sharp’s collection, still as an unidentified Agonum. Fowler (1886) refers to these specimens (one male and two females) having been collected “about 20 years ago” which would place the date to 1866. It was Fowler who sorted out the identification of those three specimens and added Agonum chalconotum (as Anchomenus Sahlbergi) to the British (and European) list in his 1886 note.
J.E. Murphy (1918) then rediscovered Agonum chalconotum on the Clyde in May 1909, this time on the south shore in Renfrewshire (VC76), collecting a single specimen which he recognised as Agonum chalconotum some months later. He was able to return for a further search in 1914 and “succeeded in finding two female examples, under stones at a spot some distance from the river and quite a mile from where the first was procured”. Sadly, Murphy (1918) gives no further detail of the locality. He does mention that on both occasions on which he found Agonum chalconotum specimens, they “were … in company with parumpunctatus [i.e. Agonum muelleri]”. It has not been found alive in Britain since.
Hyman and Parsons (1992) thought that Agonum chalconotum was “probably extinct” in Britain and that it was “a glacial relict species or possibly an accidental introduction”. Luff (2007) omitted Agonum chalconotum from his keys describing it as a “possible former resident native”. However, Lindroth (1960) presents an authoritative case for the species being a native in Britain. It is nevertheless a remarkable species to have occurred in Britain given that its world range seems to otherwise cover two areas: (1) the northern coastline of European Russia from the White Sea (southern) coast of the Kola Peninsula eastwards to the Kanin Peninsula, and (2) southern Siberia with adjacent parts of northern Mongolia, eastwards to Kazakhstan. Fauna Europaea also lists the species as present in Latvia. Lindroth (1945, 1960) was not aware of any records from the Baltic so the Latvian record must be a more recent discovery.
Agonum chalconotum could easily be overlooked as Agonum muelleri, especially now that it is not included in the latest RES Handbook. One should look out for specimens similar to muelleri but lacking the colour contrast between fore-body and elytra, and see Fowler (1886, 1887), Murphy (1918) and Lindroth (1960, 1974) for further identification characters.
Fowler, W. (1886). Anchomenus Sahlbergi, Chaud., a species new to Europe. Entomologist’s Monthly Magazine, 22, 264 – 266. [Online here: http://www.biodiversitylibrary.org/item/36504#page/598/mode/2up]
Fowler, W.W. (1887). The Coleoptera of the British Islands. Vol I: Adephaga – Hydrophilidae. London: L. Reeve.
Hyman, P. S. (revised Parsons, M. S.) (1992). A review of the scarce and threatened Coleoptera of Great Britain. Part 1. U.K. Nature Conservation: 3. Peterborough: Joint Nature Conservation Committee.
Lindroth, C.H. (1945). Ground beetles (Carabidae) of Fennoscandia. A zoogeographic study. Part 2: maps. Reprinted edition published in 1992. Andover: Intercept.
Lindroth, C.H. (1960). On Agonum sahlbergi Chd. (Col., Carabidae). Entomologist’s Monthly Magazine, 96, 44 – 47.
Lindroth, C.H. (1974). Coleoptera, Carabidae. Handbooks for the identification of British insects, vol. 4, part 2. London: Royal Entomological Society.
Luff, M.L. (2007). The Carabidae (ground beetles) of Britain and Ireland. Handbooks for the identification of British insects , volume 4, part 2 (2nd edition). St Albans: Royal Entomological Society.
Murphy, J.E. (1918). Re-occurrence of Anchomenus (Agonum) sahlbergi Chaud. in Scotland. Entomologist’s Monthly Magazine, 54, 33 – 34.
 Murphy (1918) writing in 1917 refers to Mr Bishop having “met with the insect” “about 53 years ago”.