PLEGADERUS
VULNERATUS
PANZ.
(HISTERIDAE)—
A SPECIES OF COLEOPTERA RECENTLY DISCOVERED IN BRITAIN AND NOW ADDED TO THE SUFFOLK LIST DAVID R .
NASH
U N T I L 1967, only one species of the genus Plegaderus (Histeridae), was known from the British Isles. This was Plegaderus dissectus Er., a tiny rather rare beetle found in a few localities in the southern half of England in rotten wood. In 1967, A. A. Allen added a second species, P. vulneratus Panz., to the British List. The new species was then known from only three scattered counties (Surrey, Berkshire, and Yorkshire), and Mr. Allen stated that he thought the species would possibly be discovered during the following ten years in other parts of the country. As far as I am aware no records of the occurrence of the beetle elsewhere have been published since Mr. Allen's paper. Whilst collecting in Tunstall Forest, near Blaxhall Heath, Suffolk ( T M 380557), on 27th June, 1971, two specimens of a tiny Histerid of unfamiliar appearance were discovered under the bark of a small, dead, upright pine sapling on the edge of a ride bordered on one side by mature pines. The transverse furrow of the pronotum of the specimens indicated immediately that they were a Plegaderus, and at first I thought that I had found dissectusr, which has not been recorded in Suffolk. Subsequent examination proved both specimens to be P. vulneratus. A further visit to the locality was made on 5th December, 1971, but no further examples were found. The area in which the specimens occurred, consists almost exclusively of extensive plantations of Scots pine (Pinus sylvestris), with many dead, still-standing saplings. It would seem likely therefore, that more intensive searching may prove P. vulneratus to be more widespread in what would appear to be a most suitable area for colonisation. P. vulneratus appears widely distributed in Europe, and in common with many Histerids is probably predatory—in this case possibly upon small insects or their larvae which occur under loose pine bark. P. dissectus on the other hand, appears seldom, if ever, found under pine bark—I have found this species associated with rotting horse chestnut (Aesculus hippocastanum) in Wiltshire, and with beech (Fagus sylvatica) in Hampshire.
Acknowledgements I should like to thank Mr. C. Barham for kindly checking my determination of the two specimens of P. vulneratus.
References Allen, A. A. (1968). Plegaderus vulneratus Panz., a Histerid beetle new to Bri'tain. Entomologist's mon. Mag. 104, 110.
David Ridley Nash, 266 Colchester Road, Lawford, Manningtree, Essex.
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