Gymnomerus laevipes (Shuckard, 1837) (Hymenoptera, Vespidae) new to Worcestershire and an amendment to the published record
P.F. Whitehead.
Moor Leys, Little Comberton, Pershore, Worcestershire WR10 3EH Email: paul@thewhiteheads.eu
Reference was recently made (Whitehead, 2013) to the finding of Ancistrocerus oviventris (Wesmael, 1836) at Grafton Wood, Worcestershire on 25 August 2013. I recently reviewed the specimen and decided to send it to Dr Michael Archer for examination; he found that it was a female Gymnomerus laevipes (Shuckard, 1837). This published record of A. oviventris is therefore untenable.
Richards (1980) keys the subfamily Eumeninae and states that the head of Gymnomerus has ‘two approximate occasionally fused pubescent pits’ and illustrates them as figure 25. In the present example these pits are very small, much smaller than this figure 25 and situated well behind the eyes and might be passed over; this and a subsequent failure to attend to other points of detail lead to the specimen being misidentified. Dr Archer also stated that when considering the identity of certain individuals reliance is sometimes placed on one or a few characters which require to be visible and clearly evident.
The review of this specimen by Dr Archer, to whom I grateful, is fortuitous because Trevis (2004) cited no records of G. laevipes in Worcestershire between 1990 and 2004, although it is understood that a 2008 record from Worcestershire will be cited shortly (Trevis, in press). The Grafton Wood specimen therefore helps to infill a further gap along the northern range edge. Gymnomerus laevipes is believed to subsist on larvae of weevils of the genus Hypera. Although it is recorded here in the woodland context and some species of Hypera will overwinter under the bark of standing trees, they are dominantly grassland weevils so that G. laevipes will be utilising the landscape mosaic of clearings, fields and woodland ecotones.
References
Trevis, G. 2004. Aculeate Hymenoptera in Worcestershire. Worcestershire Record 16:27-28.
Trevis, G. in press. A review of Worcestershire aculeate Hymenoptera with species notes.
Whitehead, P.F., 2014. Notable invertebrates including Rhizophagus oblongicollis Blatch & Horner, 1892 from the Grafton Wood area of Worcestershire during 2013. Worcestershire Record 35:47-48.