Gonia picea (Robineau-Desvoidy, 1830) Tachinidae, Diptera and Melanimon tibialis (Fabricius, 1781) Tenebrioninae, Coleoptera, Recorded on the Devil's Spittleful Nature Reserve 2012
The Devil's Spittleful is undergoing much-needed restoration back to heathland and the work is producing many newly cut stumps (and many stumps ground down). On a visit on 22nd March 2012 a line of freshly cut birch stumps looked interesting as sap was oozing out and on several a bacterial/fungal flux had formed. Several insects were feeding on the stumps when I spotted and photographed an unusual large Tachnid fly: several were seen in this area. It was later identified as Gonia picea (Red Data Book Rare), a southern species with apparently few records for the Midlands and none for Worcestershire (NBN Gateway). Recent reports indicate that it has increased in numbers and range in 2012 due to the exceptional warm spring weather (as now in March 2012).
A distinctive fly with a unusual head, it is an early vernal species seen March to May after overwintering as an unenclosed adult. It is a parasitoid of Cerapteryx graminis (Antler Moth), Mythimna comma (Shoulder-striped Wainscot) (Noctuidae) and Polygonia c-album (Comma butterfly) (Nymphalidae). Its habitat is said to be long grass on chalk, meadows and wood margins. (Information taken from the Tachnid Recording Scheme Web pages). Perhaps we can now add acid grassland and scrub heathland to the list?
On the same day on a drier part of the adjacent the Rifle Range on bare sand near heather I collected a small beetle about 3-4mm long that looked slightly different from the norm. It was identified as Melanimon tibialis (tibiale) a Darkling Beetle. (Joy1932). This is a mainly coastal species with a few records inland and only one old and undated record from Worcestershire from Hartlebury Common. (NBN Gateway). Little information was found searching the web but it appears to burrow in soft sand and have a preference for sand dune locations in Britain.
Joy, N. H. 1932. A Practical Handbook of British Beetles. Vols I & II. Witherby, London.
Tachnid Recording Scheme web site http://tachinidae.org.uk/site/whatarethey.php
Fig. 1. Gonia picea Tachinidae, Diptera, at Devil’s Spittleful. John Bingham.
Fig. 2. Melanimon tibialis Coleoptera, Tenebrioninae, Devil’s Spittleful. John Bingham.