Magdalis armigera (Fourcroy, 1785)
A locally common species occuring throughout England with modern records north to Cumbria and north Yorkshire, from the west country there is only a single record, from Taunton, (although Fowler also quotes Devon) and from Wales there are single records from the west and south coasts (NBN, August 2009). Morris quotes two records from Scotland; Lanark and doubtfully, from 1853) West Perth. Host plant is usually elm (Ulmus procera), but they have also been recorded from apple (Alford, 1984), and the typical habitat is wood margins, wooded parkland and, perhaps especially, hedgerows containing the host. They have been quoted as very common on trees infected with Dutch Elm disease (Benson, 1987), and this was certainly the case through west London eg Hayes, Cowley, Uxbridge, durin the late 1970's and early 1980's following total destruction of large elms by the disease; we have often found fallen branches riddled with close set longitudinal tunnels deep into the xylem which contained dozens of adult beetles, the wood was usually dry and powdery and often so damaged that it could be pulled apart by hand. Adults occur from April or May to July and infest branches 15cm or more in diameter; eggs are laid in a chamber beneath the bark and larvae tunnel outwards forming a star shaped pattern of galleries. Included on our Watford list from a single specimen sept from the elm hedge in Rousebarn lane adjacent to Whippendell wood.

Once seen these weevils become instantly familiar; of the typical elongate and satin-black appearance of Magdalis, the toothed femora and thoracic tubercles will identify armigera.

3-4.5mm (Fowler) although smaller or larger specimens occasionally occur. Entirely black or with the antennal base and tarsi pitchy, shiny but rendered dull by strong puncturation and microsculpture. Head closely punctured, punctures wide and shallow, eyes rather flat; continuous with outline of head. Rostrum shiny and finely punctured, parallel sided with scrobes not visible from above. Antennae inserted in anterior third in male, around middle in female. Scape sinuate and weakly expanded at apex, funiculus 7 segmented; first two segments elongate, remainder quadrate, club long and pointed. Pronotum quadrate or slightly transverse, without borders; lateral margins weakly curved, broadest a little behind middle and constricted before base. With a strong lateral tubercle behind front angles. Hind margin sinuate; backwardly produced at centre. Surface closely and strongly punctured, more pronounced than on head, depressed behind front margin. Elytra dilated behind middle, basal margin curved and raised around scutellum, apices separately round. Each with ten (including marginal) complete, well impressed and punctate striae, puncturation becomes weaker towwards apex. Interstices at least twice as wide as striae; weakly convex and strongly transversely rugose. Pygidium strongly and closely punctured. Femora relatively long; longer than tibiae, meso and meta femora with a small ventral tooth, profemora with a large and sharp tooth below. All tibiae with a well developed inwardly curved spur on outer side at apex (in our specimen these spurs are testaceous). Claws free (not fused at base), strongly curved and toothed at base.

Description from 1 Watford specimen at X20

References
Alford, 1984 A colour atlas of fruit pests. Wolfe science. London
Bevan, 1987 Forest insects HMSO. London


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